The terminal facilities of the Panama Canal, which have been authorized as a part of canal construction work, are costing about $32,000,000, toward which the Panama Canal furnishes about five- sixths of the funds from Congressional appropriations, and the Panama Railroad one-sixth out of its surplus revenues. This work was practically completed by June, 1916.
Terminal work includes:
First: The breakwaters and harbor dredging, authorized by the “ Spooner Act ” of June 28, 1902, which provides for the construction of “ safe and commodious harbors at the termini ” of the canal; and
Second: The necessary conveniences for vessels using the canal and terminal harbors, such as docks, piers and other water front improvements, dry docks, repair shops, cranes, storehouses, fuel plants, etc., which are being provided in accordance with the Panama Canal Act of August 24, 1912, which authorizes the President “ to establish, maintain and operate, through the Panama Railroad Company, or otherwise, dry docks, repair shops, yards, docks, wharves, warehouses, storehouses and other necessary facilities and appurtenances for the purpose of providing coal and other materials, repairs and supplies for vessels of the Government of the United States, and incidentally for supplying such at reasonable prices to passing vessels.”
The canal and terminal works have been so planned and constructed as to keep within the cost limit of $375,200,900 fixed by Congress, in accordance with the Isthmian Canal Commission’s estimate of December, 1908. This estimate included under terminals only amounts for breakwaters in Limon Bay, and for loans to the Panama Railroad with which the latter could construct a coaling plant and some permanent docks and piers at Cristobal. Other terminal requirements did not develop and were not given consideration until after 1908 Over one-third of the Panama Canal’s share of the cost of terminal facilities has been derived from savings resulting from construction work costing less than as estimated in 1908, and from the item “ for contingencies ” in the estimate of 1908.
About two-thirds of the terminal work has been designed and constructed under the supervision of the writer as Engineer of Terminal Construction, reporting to the Governor of the Panama Canal. The balance was largely performed before the Division of Terminal Construction was established. Civil Engineer F. H. Cooke, U. S. N., performed important services on the Isthmus in connection with the design of the dry docks, coaling plants, floating cranes, and of other terminal projects.
General
During the 30 years between 1851, when the Panama Railroad began operating between Colon and Gatun, and 1881, when the French started work on the Isthmus, no harbor improvements were undertaken in Limon Bay other than the construction by the railroad company and by two steamship companies of a few wooden piers, although the Atlantic coast was subject to periodic storms called “Northers,” which caused great damage in the unprotected bay. Between 1857 and 1879 seven severe “Northers” occurred that wrecked 29 vessels and destroyed or damaged the piers. American naval officers who were delegates to the International Congress in Paris in 1879, recommended the construction of a breakwater at Colon, extending out from Manzanillo Point, to improve these conditions. The construction of such a breakwater, 1000 meters long, was approved in 1881, but before it was undertaken the French transferred all of their activities from the Colon water-front to the mouth of the proposed canal at Cristobal Point, and secured the required protection for their construction plant, as well as for the canal entrance, by building a mole on which they afterwards constructed the present town of Cristobal. The French intended that their permanent wharves and piers, coaling plant, dry docks and shop facilities, should be located along the north side of the canal between Cristobal and Mount Hope, with an inner harbor or basin just inside of Cristobal Point.
On the Atlantic side, the average tidal range is 11 inches, and the extreme range 2 feet 8 inches. On the Pacific side the average tidal range is 12.3 feet and the extreme range 21.8 feet. Freedom from storms on the Pacific side renders the protection of the anchorage ground and canal entrance by breakwaters unnecessary.
On the Pacific side the French plans for a sea level canal included an inner dredged basin stretching southward from Corozal towards Sosa Hill, to be called “Panama Harbor.” The adoption of plans for a lock canal in 1887, owing to lack of funds to complete the sea level canal, and the completion in t888 of the canal channel to a depth of nine meters from old La Boca to the sea, led to the determination to establish terminal piers at La Boca, and to abandon the transfer of freight and passengers on the Pacific side by lighters that tied up during high tide at the old wooden railroad piers in Panama City. The failure of the old French canal company in 1889 delayed any action being taken on this plan until after the new French canal company was organized in 1894. The result of negotiations started in 1895 between the new canal company and the railroad company led to the construction of the old La Boca steel pier, which is still in useful service, and which, together with a turning basin and accessories, including an embankment, railroad yards, etc., cost the Panama Railroad $2,188,000, and was known as La Boca Terminal. It was completed in 1898.
When the United States took control on the Isthmus in May, 1904, one of the most pressing necessities was additional wharves and piers for receiving and handling the large quantities of materials and supplies needed for construction purposes. The Panama Railroad treasury was empty, so the Isthmian Canal Commission had to spend over half a million dollars for temporary docks and for dredging at the terminals. Most of these docks were afterwards leased to the Panama Railroad. On June 29, 1906, Congress approved a lock canal of the general type proposed by the minority report dated January 10, 1906, of the Board of Consulting Engineers, that had been appointed by the President. This report recommended harbor protection at the Atlantic Terminal along the lines originally proposed by the French: that is, by means of a breakwater extending out from Colon beach near Manzanillo Point. A west breakwater paralleling the canal through Limon Bay was also proposed. An alternative suggestion was to omit this latter breakwater and double the proposed canal width to 1000 feet. This would have afforded a protected harbor larger than that obtained by the French plan, but much smaller than that which has been obtained under the plans which were afterwards adopted. The Hoard recommended the completion of the inner harbor south of Cristobal Point: that was originally proposed by the French for wharves, coaling facilities, etc. At the Pacific end the minority report of the Consulting Board included provision for a set of two-lift locks to be located on the west slope of Sosa Hill. No special harbor protection was considered necessary, and no recommendations were made for terminal piers and other facilities.
For three years after the adoption of the lock canal project, all efforts were concentrated on canal construction work, and while the necessities for permanent terminals were gradually developing, and ideas in regard to this work were slowly crystallizing, no definite action was taken until the latter part of 1909, when the appointment of a joint Army and Navy Board on Fortifications and the increasing requirements for additional wharf room assisted in bringing matters to a head.
In 1907 it had been decided at the Capitol in Washington that any appropriations for the defence of the canal would be included among the appropriations made for the War Department, and that the fortifications would be constructed by the War Department; with the understanding that no estimates would be submitted until efforts to secure the ratification of the necessary treaties that would insure the neutrality of the canal had been abandoned. The duties assigned to the Panama Canal Fortification Board included matters connected with the availability of land that might be required for naval purposes. The naval members of the Board were also required to obtain information of use in connection with the establishment of naval repair stations.
A tentative selection of sites for dry docks, repair facilities including storehouses, fueling plants, wharves, and other naval utilities, was made at Mindi on the Atlantic side, and at Diablo, between Corozal and Balboa, at the Pacific end. These locations were not the most desirable or economical, as the Board was restricted in its choice to land not reserved for canal use. The Isthmian Canal Commission expected that there would be also required for canal and commercial use, a permanent repair plant and dry dock, fueling plants, storehouses and wharves and piers, and considered that a duplication, solely for military use, of these utilities, that would have to be provided for the canal in any case, would be undesirable and unnecessary. At a meeting held in April, 1910, it passed the following resolution:
“That economy in the administration of the Panama Canal, both before and after completion, requires adherence to the principle that such facilities, appurtenances, etc., as may be required for its construction, sanitation, operation, maintenance, repair, defence, and commercial use, and by the Panama Railroad Company and by the Canal Zone Government, shall be combined and consolidated, so far as practicable, without duplication, regardless of their use hy more than one executive department of the government.”
Subsequent conferences between representatives of the navy and the canal led to the formulation and adoption in November, 1910, with the approval of Washington, of a policy that was designed to give satisfactory service to all departments and interests concerned with the least expenditure of money. This policy, which is still in effect, gives the navy satisfactory control and supervision over the facilities in which it is especially interested, by the examination and approval in Washington of general plans before work is started, and by detailing naval officers as its representatives for duty under the Governor of the Panama Canal on the Isthmus, in connection with design, construction and operation, of naval facilities. The comparatively small repair plant and dry dock at Mount Hope that has served the needs during the construction period will be maintained as long as required, and the construction of a large modern plant, similar to that at Balboa, will await the development of future requirements. Requirements solely for naval purposes are to be paid for from naval appropriations; facilities provided to meet canal and commercial needs are paid' from canal appropriations.
The Panama Canal has proceeded with the design and construction of its terminal facilities in accordance with the above procedure. In July, 1910, the first steps were taken to increase the berthing space at each end of the canal by the construction of permanent wharves and piers. Congress had not yet authorized any expenditures of this nature in connection with the canal. Therefore, this work had to be undertaken at the expense of the Panama Railroad Company. At Balboa, the first section of permanent wharf, 650 feet in length, forming a part of present Dock No. 15, was authorized in September, 1910, and completed by the Panama Canal for the Panama Railroad in July, 1912. The passing by Congress of the Panama Canal Act of August 24, 1912, permitted subsequent terminal work to be undertaken and paid for by the Panama Canal.
On the Atlantic side, the Panama Railroad at first favored locating the permanent docks along the south side of Cristobal Point adjacent to the entrance of the French canal, where the French intended to locate their docks. On account of the inadequate room for railroad yards and the unsuitable character of the bottom, further consideration led to the abandonment of this plan and resulted in locating, in the latter part of 1910, the permanent docks and piers, in the Canal Zone, behind a mole constructed out into Limon Bay from Cristobal, which plan has since been followed.
At the Pacific end, it was first planned, in 1910, to dredge an inner basin behind Sosa Hill, with the wharves and piers for commercial use along the south side; and the repair plant, dry docks, and other naval facilities grouped along the north side at Diablo Hill. Considerations of economy and the policy of consolidation which was adopted in November, 1910, resulted in the abandonment of this plan, and the adoption, in May, 1911, of a project which combined the results of both individual investigation and committee reports. This plan retained the feature of an inner basin, and grouped the dry docks and repair plant along its south side under Sosa Hill, with the commercial wharves adjacent thereto, and a system of five commercial piers at the head or east end of the basin, and jutting out into it at right angles to the canal. This plan has since been followed. Both the general plan of the terminals, as well as the general plans of the various units, including shops, fueling plants, dry docks, etc., were submitted to the Navy Department for review and recommendation before starting work.
The following is a general description of some of the terminal works:
The Atlantic Breakwaters
Harbor protection in the form of breakwater construction at the Atlantic terminal includes the West Breakwater, the East Breakwater, and Cristobal Mole. The West Breakwater was authorized in 1910 and completed in May, 1914. It extends from Toro Point Light in a northeasterly direction in a straight length of about 11,378 feet to within 1000 feet of the center line of the canal, which has a channel width of 500 feet. At its outer end the depth of water is 44 feet and there is a small ell or return 223 feet long, behind which has been placed the breakwater light. The anchorage ground, hounded by the West Breakwater, the canal channel, and the 30-foot contour, has an area of about three square miles, and that bounded by the breakwater, the canal channel, and the 36-foot contour, has an area of about one and one-half square miles. This breakwater consists of “core rock" carried up to within about 12 feet of the surface, on which was plated larger rock termed “armor rock,” to a height of ten feet about sea level. This breakwater cost about $3,500,000 or $300 per running foot. It contains about 2,000,000 cubic yards of material.
Cristobal Mole will be, when completed, about 4000 feet long. It extends out into the bay from Cristobal at right angles to the canal channel. It is being extended from time to time as required to protect the piers which are being constructed on the south side of the mole. Two of the five piers, Nos. 7 and 8, for which there is room, have been constructed, and work on a third pier, No. 6, for which an appropriation has just become available, has started. The present length of the mole is 3000 feet. It consists largely of rock fill armored on its north side. It has cost approximately $500,000. When it was authorized in 1910, it was thought that the furnishing of this protection to shipping lying south of the mole at the permanent docks and piers would render the construction of the East Breakwater unnecessary. Experience led to strong recommendations being made for the Isthmian Canal Commission to consider favorably the construction of the East Breakwater, and in view of the added safety that would be secured for the Atlantic terminal harbor through its construction, and of the estimated lessened cost of maintaining the channel through the soft mud of Limon Bay, its construction was finally authorized in 1913. The East Breakwater is a “detached” breakwater with its outer end opposite the outer end of the West Breakwater. There is an opening of 2000 feet between the breakwaters. The breakwater has a 225-foot ell at the outer end. It extends shoreward a distance of 6516 feet, making a total length of 6741 feet. Its inner end is 4467 feet from the shore at Coco Solo Point. The breakwater has not been continued to the shore, as this additional length would be of little or no value as regards increased canal and harbor protection. The breakwater has been built mainly of rock, and is similar in cross section to the West Breakwater. Above the surface of the water and down to elevation-12, concrete blocks have been largely used in lieu of “armor” rock. The concrete cubes were manufactured in various sizes from 4' 3" on a side, weighing 5 1/2 tons, to 7' on a side, weighing 25 tons. The quantities in the completed breakwater, costing about $3,300,000, include the following:
| Cubic Yards |
“Core” rock | 682,000 |
Hydraulic and scow fill | 650,000 |
“Armor” rock | 68,000 |
Concrete blocks | 200,000 |
The construction was rendered more hazardous and expensive by the necessity of maintaining the unfilled wooden trestle nearly a mile in length, connecting the breakwater with the shore at Coco Solo Point, over which the rock fill was transported. Two unusually severe “Northers” visited Limon Bay during the construction period, one in February, and one in April, 1915. These “Northers” destroyed nearly all of the construction trestle, delayed the completion of the breakwater six months, and caused damage to the extent of nearly $400,000 in connection with the breakwater. The trestle was promptly redriven and the dumping of rock was resumed in the latter part of July, 1915. The rock fill was quarried at Sosa Hill on the Pacific side, and was transported 50 miles across the isthmus and dumped in place for $1.01 per yard, including all costs except that for trestle construction.
During 1914 some small dikes were built out from the south shore of Limon Bay close to the canal channel to assist in retarding the movement of silt which the wave action on the muddy shores resulted in depositing in the channel. Prior to 1915 severe “Northers” always caused a large amount of soft mud to be deposited in the canal channel. The two “Northers” of 1915 increased the maintenance work in the canal channel by less than 60,000 yards. The reduction can be attributed in some small part to the effect of both the West Breakwater and the Cristobal Mole, but it is probably more largely due to the above-mentioned dikes and to the present flatter slopes of the sides of the dredged channel at the upper end of the bay.
The anchorage ground bounded by the East Breakwater and the 30-foot contour, and included between north and south lines passing by the outer end and by the inner end of the breakwater, has an area of 1,5 square miles. The area of the anchorage ground included between the breakwater and the 36-foot contour, is one square mile.
The Pacific Breakwater
At the Pacific terminal, the removal of the double-lift locks inland from Sosa Mill to Miraflores, which was approved in 1907, and the straightening of the channel so as to pass to the west of Naos Island, in connection with finding a convenient place to dispose of soil excavated from the south half of Gaillard Cut, opened the way for the approval in 1908 of a project to connect Naos Island with the mainland by a dike or breakwater, which was completed in September, 1914, at a cost of about $800,000. This cost includes only the cost of the trestle and the excess cost of dumping the material over what it would have cost if disposed of in the cheapest manner. The principal value of this breakwater, which has a length from Naos Island to the original shore of about 3.3 miles, is the protection it affords to the dredged channel as regards deterioration, caused by silt bearing tidal currents that would otherwise sweep from the northeast to the southwest across the channel. Balboa dump, which has been made from spoil from Gaillard Cut by widening the inner half of the breakwater, has furnished a site for a radio station, a quarantine station, a fuel oil plant and tank farms, and has served other useful purposes in connection with the Pacific terminals. For its outer 6500 feet, the breakwater has a width of 40 feet, with its top about 18 feet above sea level. A highway and a railroad track have been built on the breakwater.
The Pacific Terminal Plant
The Pacific terminal plant has been designed with a view to meeting the combined canal, railroad, naval, military and commercial requirements. It has been located at old La Boca, now renamed and called Balboa. It consists of the following' principal units:
(A) Two dry docks.
(B) Repair shops including storehouses, storage yards, tracks, and other accessories.
(C) Fueling plants, including both coal and oil.
(D) Wharves and piers for canal, naval and commercial use, including berths for vessels under repair.
Dry Docks.—There will be two dry docks; No. 1, of sufficient size to dock any vessel that can pass through the canal locks; and No. 2, which will be of smaller dimensions. The layout of the repair plant at Balboa was determined and worked out after first fixing the location of Dry Dock No. 1, where it could be built on rock.
The principal dimensions of Dry Dock No. 1 are:
| Feet |
Width at entrance | 110 |
Width in body on floor | 113 |
Width in body at coping | 143 |
Length on center line, from miter sill to head | 1044 |
Length on center line, from head to caisson sill | 1102.67 |
Elevation of top of blocks referred to mean sea level | —35.0 |
Elevation of miter and caisson sills referred to mean sea level | —39.5 |
Elevation of coping referred to mean sea level | +16.5 |
The dock is built on rock and is composed of about 185,000 cubic yards of plain and reinforced concrete, the greater part being plain or mass concrete. The floor consists in general of a 12-inch concrete lining placed directly on the rock. Where pockets of fractured or partially decomposed rock were met the thickness of the floor was increased. The side walls of the dock are gravity retaining walls. At the bottom of each wall is a large culvert. Each culvert has 17 grated openings leading to the floor of the dock, equally spaced longitudinally. These distribute the water in flooding the dock, and reduce longitudinal currents; and in the last stages of pumping out the dock these openings assist in the rapid unwatering of the floor of the dock. The dock has side altars of heights adapted to navy requirements, all altars being 3 feet wide. At the coping level the dock is equipped with a 5-foot gauge railroad track and a 22-foot gauge 50-ton locomotive crane track. Air and fresh water conduits are carried down to the floor of the dock in the side walls at frequent intervals. The dock has been equipped with four stairways on each side and two material slides. The center keel blocks arc of cast-iron of the wedge type, with a white oak top block, and have a total height of 4 feet 5 inches. The docking keel blocks and the sliding bilge blocks are of standard navy type of greenheart and white oak with galvanized metal fittings. The entrance to the dock is closed by a pair of steel miter gates electrically operated of a type similar to the miter lock gates, except that the dry dock has granite sills and hollow quoins in lieu of wooden and steel sills and nickel steel bearing plates for the hollow quoins on the lock gates. The miter and quoin ends and clapping sill of the dock leaves arc of greenheart. All exposed metal work of the gates has been protected by bitumastic enamel. The greenheart is immune to attacks of teredo. The gates can he completely opened or closed in less than two minutes. An outer sill of granite has also been provided in which can be placed the floating caisson, which has been provided for use in making repairs at the canal locks. This caisson has its own pumping plant, and can be used to give access to the outside of the dock gates for cleaning and repairs. The dry dock is equipped with cast-iron bollards spaced 55.5 feet apart along the side walls and set 40 feet back of the coping, and with nine electrically- driven capstans capable of developing a rope pull of 35,000 pounds at a speed of 30 feet per minute. The dock is fitted with the accessories usual with naval docks. The pumping plant for both Dry Dock No. 1 and No. 2 is located on the south side of Dry Dock No. 1, near the entrance. It consists of four main pumps, two drainage pumps and one bilge pump. Each main pump is a single bottom suction, vertical shaft, volute centrifugal pump of 34 inches discharge diameter. The average rated contract capacity of each pump is 11,000 cubic feet per minute. Each pump is driven by a 1000 horse-power, 3-phase, 2200-volt induction motor, located at the ground level vertically above the pumps. The valves controlling the operation of the pumps, as well as the main culvert valves, are operated hydraulically at 300 pounds pressure. The dock has been designed to be unwatered in about two and one-half hours, and can be flooded in less than 30 minutes. During the acceptance tests of the pumps and valves these times were considerably bettered. In the pump-house, which is 59' 10" x 255', there has been installed in addition to the pumps, the main air compressor plant for the shops, consisting of one 2250 and one 5500 cubic foot motor-driven compressor.
All work in connection with the construction of the dock, including the installation of the pumping plant and the erection of the dock gates, has been performed by the forces of the Panama Canal. The dock will cost, complete, about $2,700,000.
The body of the dock and the entrance gates were ready for use on April 1, 1916, though the blocking system and a number of accessories had not been installed due to the non-delivery of material.
The final shot for breaking a gap through the cofferdam which has protected the entrance basin, the dry docks, coaling plant and adjacent quay wall work during the construction period, was made, and the entrance basin and dry dock were completely flooded on April 23, 1916, after which the gates were closed, and the dock was unwatered by a portable pumping plant, the installation of the permanent pumping plant not having been entirely completed. After April, the use of the dock was contingent upon the removal of the cofferdam. The dock has been used as required since July, 1916.
A smaller dry dock, No. 2, has been located parallel to Dry Dock No. 1, and immediately northwest of the entrance thereto. This dock will have the following dimensions:
| Feet |
Width at entrance for full height | 72 |
Width in body at floor | 75 |
Width in body at coping | 92 |
Elevation of sill and floor, referred to mean sea level | —22.83 |
Elevation of top of blocks, referred to mean sea level | —18.33 |
Length on floor from caisson sill to head wall | 366 |
Overall length on floor from outside of masonry to head wall | 381 |
This dock will be rectangular in plan with side and head walls of concrete. The floor will be concrete, about one foot thick, laid on rock. The dock will he provided with a floating caisson which will bear on a granite faced seat. The dock will have stairs on each side at the entrance and head, with a material slide alongside the stairways at the head. The dock will be equipped with the necessary capstans and bollards, and will be served by the same pumping plant as Dry Dock No. 1. The excavation for this dock has been completed and the concrete for the south side-wall and the head wall has been laid. The south side-wall forms a part of the north guide wall or entrance pier to Dry Dock No. 1.
After Dry Dock No. 2 had been planned, and funds had been allotted for its construction, some doubts were expressed by Members of Congress while on the Isthmus as to the advisability and necessity of proceeding with the work until Dry Dock No. 1 was unable to handle the volume of business offered. This led to the adoption of the program which has been followed since 1914, of completing Dry Dock No. 2 only so far as necessary for the convenient operation of Dry Dock No. 1, and of awaiting actual experience as to the amount of work there will be for Dry Dock No. 1, and specific authority from Congress before going further. To complete Dry Dock No. 2, and remove the material at its entrance, will cost approximately 8400,000.
Balboa Shops
The permanent repair shops are intended to meet all the varied requirements incident to the canal, the navy, the army, the Panama Railroad, the Panama government and citizens of Panama, and of commercial shipping. The main buildings are located in an area 635.5 feet wide measured between Dry Dock No. 1 and the sea wall parallel thereto and 2500 feet long. The main metal working shops, including machine shop, boiler shop, pipe shop, blacksmith shop and storehouse for metal, are 3fxi feet in length and are placed at right angles to the dry dock, and provided with overhead traveling cranes with runways extending beyond the ends of these buildings, so as to span two railroad tracks which pass by each end of these buildings. These tracks, together with a track passing across the center of each of these buildings, afford economical facilities for receiving and shipping material and equipment. The remainder of the shops, including the wood-working shops, storehouses, foundry, car shops, paint shop, etc., are located further to the east, and arc parallel to the water front. A 3-story office building is located close to the center of the shop yard and adjacent to the water front.
The buildings all have steel frames. The main shops are surrounded by a concrete curtain wall 3 feet 6 inches high, above which the sides arc closed in by galvanized steel louvers, which, being easily adjustable, afford ample ventilation and protection against sun or rain, and can also be easily closed at night. The main door openings arc closed by steel rolling doors. California red-wood has been used for mill work, including window sash, smaller doors, monitor louvers, etc. Creosoted wooden blocks laid on a concrete base have been used on the floors where concrete, cinder, clay, or earth floors are not suitable. For the roofing, reinforced concrete red “Bonanza” tile, manufactured on the isthmus, was used with special tile set with skylight glass wherever additional light was needed.
The shops are electrically operated, the current used being 3-phase, 25-cycle, delivered from the Balboa substation at 2200-volts, and stepped down to 220-volts for the shop power circuits. Switchboards and transformers arc located near the load centers of groups of buildings. Induction motors are used for group drive and for all constant speed machines; 220-volt direct current motors are used where variable tool speed is desired. The total rated horse-power of motors is about 5000.
The buildings have been liberally supplied with overhead electric traveling cranes up to 60-ton capacity, and also with the necessary equipment of jib and pillar cranes. For night work the shop buildings have been thoroughly lighted, avoiding the use of portable lamps and securing high efficiency for night operation. All lighting circuits arc single phase, 110-220 volts. Lamps are tungsten filament of 100-watt, 150-watt, 250-watt, and 500-watt. Air, water, oil, steam, and sewer pipes, and light and power cables, are carried under and between the shop buildings in a reinforced concrete tunnel 4 feet 6 inches wide by 6 feet high, which makes them easily accessible.
File size of each building was fixed by the estimated future requirements, as well as the requirements in sight during the construction period. The buildings were made large enough to accommodate such of the large number of tools and machines on hand as were considered of value for permanent installation, and this in many cases fixed the size. In addition, allowance was made where considered necessary, for the installation of new special tools that it might be found necessary to purchase in the future to serve navy and other necessities that might arise. Of the original installation, comprising a little less than 400 machines, over 90 per cent were on hand and less than 10 per cent were purchased for the new shops. The accompanying table gives the dimensions and floor areas of Balboa shop buildings. The buildings, machinery installation, operating tunnel, etc., complete, have cost about $3,800,000.
The mechanical division operates these and other shops on the Isthmus, including those at Paraiso, which are being maintained to serve the dredges and other marine equipment at work in Gaillard Cut and Gatun Lake. At the Atlantic end there is also at Mount Hope a marine equipment repair plant, known as the Cristobal shops, started in the French days, and the old French dry dock, which was enlarged in 1908 to meet the requirements of canal construction work. Its entrance is closed by a pair of wooden miter gates. Its dimensions are:
| Feet |
Length from head to entrance | 300.8 |
Total length from miter sill to head measured on center line | 316.6 |
Width at entrance, full height | 49.95 |
Width in body at coping level | 69.33 |
Depth of water over sill (referred to mean sea level) | 13.4 |
This dock has been constantly busy since the early construction days. Before the canal was opened, the larger vessels and floating equipment on the Pacific side were beached at Naos Island at high tide or deposited on the “gridiron” at Balboa. Barges and smaller equipment were repaired on the shipways at Balboa. As the elevation of the floor of the upper locks at Gatun is 14 feet above sea level, these locks can he entirely unwatered by gravity, and though the locks were not specially designed to carry the load imposed by vessels being dry docked therein, they can and have been used as dry docks, as in the case of the floating cranes and submarines. By using the locks flouting caisson, which is equipped with a pumping plant, the other locks could, if necessary, be used for dry docking purposes.
The superintendent of the mechanical division is, by executive order of January 27, 1914, a naval constructor, reporting to the Governor. The expenditures of the mechanical division for labor and material are averaging about $400,000 per month, and the number of employees is 2600.
Floating Cranes
Two 250-ton floating cranes of the revolving derrick type have been furnished as a part of the canal equipment. The number, capacity, and type were determined by the desire to provide facilities that would be readily available to step or unstep a lock gate leaf expeditiously, should the necessity ever arise. In fixing the reach, and the height to which the hooks can be raised, naval requirements have been met.
The cranes were purchased under general specifications issued by the Panama Canal, award going to the United States agents of a German firm, the Deutsche Maschinenfabrik A. G. of Duisburg, the lowest bidder, on cranes of a type that it had furnished many foreign governments and private shipyards, and that were in successful use. The contract price of each crane erected and delivered was $423,750. The Hercules was accepted in March, 1915, and the Ajax in September, 1915, and since then these cranes have performed useful service in connection with canal and commercial work, in handling heavy guns and equipment, and especially in connection with repairs to dredges working in Gaillard Cut. Each crane consists of a steel pontoon 150' 2 3/8" long, 88'9 3/4," wide, and 15' 9" deep at each side with a deck camber of 12", containing a power plant and supporting the fixed and revolving superstructure. The power is steam-electric. Direct current at 220 volts is generated. All motions of the hooks are controlled by one operator. The pontoon is not self-propelling. It is divided by bulkheads into 26 water-tight compartments adjacent to the outside plating and 15 internal compartments not water-tight.
The fixed superstructure consists of a truncated steel framed pyramid which supports the revolving superstructure at its top. The latter consists of the "bell,” which is a steel framework surrounding the pyramid and supporting the jib, the machinery-room, and the operator’s cab; and the jib which is hinged to the “bell” at its top and carries the main and auxiliary hoists. Rotation about a vertical axis is accomplished by power applied between the “bell” and pyramid at the base. Movement of the jib in a vertical plane is secured by means of two links, attached to the jib, and to carriages driven by vertical screw spindles located at the rear of the “bell.” The design eliminates uncertainty as to how the loads are carried. All vertical loads, “dead” and “live” of the revolving superstructure are carried at the top of the pyramid. The overturning moment of the live, dead, and wind loads is resisted by horizontal forces applied at the top and bottom of the pyramid. An area on the deck of the pontoon. 20' x 60', is designed to carry a live load of 2000 pounds per square foot.
The jib is provided with a main and an auxiliary hoist. The former is fixed at the point of the jib and consists of two blocks each of 125 gross tons capacity, arranged so that they can be linked together by an “equalizer bar” to form one hoist of 250 gross tons capacity. Each main hoist block is suspended by 10 parts of 2-inch wire rope. The auxiliary hoist has a capacity of 15 gross tons and consists of a two-part block swung from a traveling trolley supported on a runway on the lower side of the jib. The main hoist can handle the maximum loads while revolving completely, and can also be luffed in and out. The main hoist was required to have the following capacities at the reaches stated, “reach” being the horizontal distance from face of the pontoon fender to center of block. Before acceptance they were subjected to loads 20 per cent in excess of their rated loads.
| Tons of 2240 pounds | ||
Maximum rated load | 100 tons | 150 tons | 250 tons |
| Feet | Feet | Feet |
Reach over end | 80.1 | 59.0 | 21.0 |
Reach over side | 81.6 | 62.4 | 22.3 |
The maximum height of hook on equalizer bar above water is as follows:
| Feet |
In 100-ton position | 126 |
In 150-ton position | 154 |
In 250-ton position | 182 |
The speed of hoisting the main blocks is as follows:
| Feet per minute |
With 250-ton load | 3.5 |
With 125-ton load | 7.0 |
With 62 ½-ton load | 14.0 |
The auxiliary hoist was tested to 33 1/3 per cent excess load over its rated capacity, or 20 gross tons, before acceptance. The speed of hoisting the auxiliary block fully loaded is 40 feet per minute.
Depending upon conditions, the crane can make one complete revolution in from five to eight minutes. The average freeboard of the pontoons of the unloaded cranes when tested was 8.25 feet, and the minimum freeboard for the loaded cranes without deck load was about 2.8 feet. The maximum longitudinal inclination of the pontoon was approximately two degrees, and the maximum transverse inclination 4 1/2 degrees for loads within the rated capacity. The total weight of material in each crane, including pontoon, concrete counterweight, etc., is approximately 3400 short tons. These cranes have proved themselves to be exceedingly useful through their great flexibility.
Fueling Plants
No expense has been spared by the Panama Canal to make the canal fueling plants adequate for all requirements. As a measure of economy, in designing the coaling plants, arrangements for the storage of coal were so made that all coal for canal and commercial use could be handled by the same machinery. Following the adoption in January, 1913, of the policy by which the United States retains direct control of all the shore line and improved water front at the terminals, it became necessary to provide sufficient area in the coaling plants for leasing to individuals and companies desiring to store and sell coal on the Isthmus. Existing legislation does not permit the leasing of any land in the canal zone, except for agricultural purposes, and land could be occupied by a private coal plant only under a revocable license issued by the Panama Canal, terminable at the pleasure of the government, without liability for reimbursement on account of any improvements made. This is not a situation that would encourage the investment of capital in private coaling plants on the Isthmus, even if they were desired by the Panama Canal. About one-third of the storage area of each coaling plant has, therefore, been made available for use by individuals and companies if desired. A large number of tentative applications for space have been received, but with the low price for Panama Canal coal, and with the present high transportation rates, there is no opportunity under present conditions for any private company to enter the coal business at the Isthmus at a profit, and no leases have thus far been made.
During the canal construction period, the Panama Railroad has handled the sale of all coal on the isthmus, the amount in long tons by fiscal years being as follows:
1905 | 75,673 |
1906 | 130,383 |
1907 | 203,451 |
1908 | 368,331 |
1909 | 357,125 |
1910 | 481,039 |
1911 | 490,864 |
1912 | 491,494 |
1913 | 462,246 |
1914 | 325,646 |
1915 | 369,955 |
A total of 3,756,207, tons in 11 years.
For the fuel oil plants, the Panama Canal retains similarly control of the oil berths, and requires all oil to be handled through the Panama Canal pumping plants for which the present charge is 3 1/2 cents, each way, per barrel of 42 gallons. Tank farms at each terminal have been laid out where the land is not needed for other purposes, divided up into lots for oil tanks, and leased to oil companies under revocable license. The policy of United States control of all transportation across the isthmus, and the desire not to permit any method of transportation that would lessen canal traffic, effectually bars the construction of a trans-isthmian oil pipe line by either the Panama Canal or by any private interest. In 1906 the Union Oil Company was permitted to lay an oil line across the isthmus under a revocable license, under the terms of which the Panama Canal could purchase such oil as it required during the construction period. This line was taken up when this license expired on December 31, 1914, and since then the Panama Canal has supplied requirements with its own plants. The purchases of fuel oil from the Union Oil Company during the fiscal years given, in barrels of 42 gallons, were as follows: For the greater portion of this oil, the price was $1.10 per barrel, delivered into Panama Canal service tanks.
1907 | 6 |
1908 | 17,405 |
1909 | 239,623 |
1910 | 1,143,539 |
1911 | 888,940 |
1912 | 604,137 |
1913 | 675,407 |
1914 | 365,850 |
1915 | 198,500 |
Total | 4,223,506 bbls. |
Two coaling plants have been built, one plant being located at the Atlantic terminal and one at Balboa.
The plant at Cristobal has been designed to unload and store coal at the rate of 1000 short tons per hour, by means of four standard unloading towers, which are being furnished by the Hunt Construction Company, and to dig from the stock pile and deliver at the end of the four reloader tower chutes coal at the rate of 2000 short tons per hour. The two large stocking and reclaiming bridges; the conveyor system, consisting of eighty-eight 10-ton capacity electrically-driven cars and supporting viaduct; the four reloader towers, the power plant, and the hunker and conveyor tower on the end wharf are being furnished by Mr. Augustus Smith, who has furnished the machinery and structural material for several of the navy coaling plants. Mr. Smith’s design for the machinery for both the Cristobal and Balboa plants was based 011 general specifications issued by the Panama Canal. All of the machinery is being furnished by him, except the unloader towers referred to above, which have been made to conform to his design. The Panama Canal built the wharf, and performed the remainder of the work, with its own forces. The plant consists essentially of a storage pile 307 feet wide and 1700 feet long, surrounded at one end, and on two sides for 1000 feet, by steel and concrete wharves which carry the viaduct and the machinery units. Coal is received from colliers along one side, called the unloader wharf, and is reloaded into colliers, barges or vessels along the other 1000-foot wharf, called the reloader wharf, On the end wharf is an elevated bunker having a storage capacity of 1500 tons, which is equipped with six adjustable chutes. The coaling pier has a total berthing space of 2588 feet, or five standard 500-foot berths. The rates for receiving and delivering coal at the Balboa plant are one-half those of the Cristobal plant; and the berthing space at the Balboa plant is somewhat more than one-half that of the Cristobal plant.
These plants, which were ready to go into operation in the latter part of 1916, have been awaiting the completion of the machinery contractors’ work since, early in 1916. It has been decided that the Panama Railroad shall operate these plants for the Panama Canal. The Cristobal plant represents an investment of about $3,500,000, including connection with the main line of the Panama Railroad across the French canal, of which about $1,650,000 has been for the machinery and the remainder has been for the steel and concrete wharves and other foundations for the machinery, dredging, grading, fill, railroad connection, etc. In addition, dredging alongside the coaling pier and adjacent thereto has cost about $500,000. The Panama Railroad has contributed $1,000,000 toward the cost of this plant, and the Panama Canal the balance.
The Balboa plant, not including the wharves—which would have been built in any case—has cost about $1,250,000. In lieu of stocking and reclaiming bridges for the Balboa plant, four large cantilever cranes, which were used on the construction of the Pacific locks, have been fitted up for this purpose. The coal docks of each plant have been furnished with fresh water and fuel oil conduits, with outlets at frequent intervals.
The present price for coal for steamships, trimmed in bunkers, and using the ship’s gear, is as follows:
At Cristobal....................................................... $8.00 per ton of 2240 pounds
At Balboa.......................................................... 0.50 per ton of 2240 pounds
Of the total cost of coal delivered at the isthmus, about one-third represents the cost at the mine, one-third-rail transportation to seaboard, and one-third water transportation to the isthmus. The first two items arc quite firmly established. It is important to the canal to control the third item, water transportation, and to be independent of commercial fluctuations in water transportation rates. It was considered of great importance, also, that the Panama Canal should transport coal to the isthmus in its own colliers. This led to representations being made along these lines, in 1912, and an appropriation being made in June, 1913, under the Panama Canal for
The construction in the United States in the government or private yards, in accordance with plans and specifications to be prepared by the Navy Department, and to have a caruo capacity of 12,000 tons of coal and a speed of not less than 14 knots per hour, two colliers to cost not to exceed $1,000,000 each.
A contract was awarded to the Maryland Steel Company for the construction of the two colliers named Achilles and Ulysses at $987,500 each in April, 1914, with time of delivery 16 months. These colliers were put in commission in June and April, 1915. respectively, and are being operated by the Panama Railroad Company for the Panama Canal in a manner somewhat similar to the operation of the vessels of the Panama Railroad Steamship Line. The cost of these colliers was excluded by Congress from the estimated cost of the canal of $375,200,900. The operation of these colliers has been so satisfactory from a financial standpoint, as well as otherwise, that an appropriation was made for the construction of two additional colliers, by the Sundry Civil Rill for 1916-1917, in view of the necessity of providing additional means for the transportation of coal to meet the growing demands of the canal. It is expected that these colliers will cost approximately $1,500,000 each.
The Panama railroad has also made arrangements to enable vessels to be bunkered while lying in the stream or at commercial docks and piers, by fitting up for this service a number of old steel barges having a dead weight capacity of about 500 tons, that have been used in the past in construction service. Two of these barges have locomotive cranes, with long booms, that operate clam-shell buckets. Two others are equipped with De Mayo towers, and it is proposed to equip two additional barges with De Mayo towers,as soon as the barges are released from construction work. Contract has been awarded the United States Steel Products Company for two steel barges for delivery early in 1917, having a capacity of not less than 500 tons of coal, and equipped with a system of horizontal and vertical continuous conveyors, and unloading chutes, as to make the barges self-discharging. There are also three 500-ton steel barges in the coal service without any discharging equipment. A half dozen additional barges of this type will be released from the construction service before 1917 and will be transferred to the coaling service.
The Panama Railroad has also made provision at the docks and piers at each end of the canal whereby De Mayo towers can he handled from booms attached to the pier sheds, and worked in specially built 50-ton coal cars to coal ships lying alongside. It is expected that quite a fleet of coal barge's will he required at each end of the canal to meet commercial requirements.
All coal is purchased by the Panama Railroad under annual contract. The contract that terminated in September, 1916, called for the delivery at tidewater, loaded into colliers, of any portion of 400,000 long tons of coal at $2.60 per ton, and permitted the Panama Railroad to purchase any portion of 300,000 tons, in addition, at $2.64 per ton.
The specifications are prepared in consultation with the Bureau of Mines, and all coal is inspected by a representative of the Bureau of Mines; and samples are taken while the coal is being dumped from cars into the colliers. The results of tests made on the samples of coal determine the adjustment made in the contract price, as described below. Coal is required to be of best quality, steaming, semi-bituminous, run-of-mine, and to contain when actually delivered not to exceed:
| Per cent |
Moisture | 3 |
Ash | 6 ½ |
Volatile matter | 21 |
Sulphur | 1 |
Fixed-Carbon, not to be less than | 72 ¼ |
British Thermal Units, per pound of dry coal, to be not less than | 14.700 |
When delivered in cars, alongside steamer, at least 65 per cent is required to pass over a screen with 3/4" square openings, and at least 30 per cent over a 3" bar screen. For coal which contains more than 3 per cent moisture a deduction in price of two cents per ton for each per cent in excess is made. Adjustment in price for B. T. U, (dry coal) variations from the standard of 14,700 is determined by the following formula:
(Variation in B.T.U.)2/7500 = price adjustment in cents per ton
In addition to the foregoing adjustment, in case the coal analyses on the “dry basis” below 14,200 B. T. U. per pound, a deduction, as a penalty, of 10 per cent of the value of such coal is made.
The fuel oil plants at each terminal include the necessary outlets on cribs or wharves, the pipe lines between the water front and the tank farms, the pumping plants, and the tanks. Doth the Panama Canal and private companies own tanks, and the latter are required to furnish the pipe lines connecting the tanks with the pumping plant. The Panama Canal owns the remainder of the pipe lines. The plants arc each able to handle oil from storage tanks to or from three vessels simultaneously, at a minimum rate of 1200 barrels per hour per vessel; and the pumps have sufficient power to make deliveries to any Panama Canal service tanks located within a radius of eight miles at the rate of 400 barrels per hour. At Balboa, oil is received at Dock No. 2, the oil crib, and at Cristobal at Dock No. 13. The receiving rate depends upon the capacity of the ship’s, pumps, and vessels have been unloaded at an average rate of over 2000 barrels per hour. Oil can be delivered at Balboa either at Dock No. 2, the oil crib, Dock No. 4, the old French pier, or Dock No. 6, the reloader wharf. At Cristobal there are outlets on Dock No. 13, and also 14 outlets along three sides of the coaling pier, Dock No. 16. The rate of delivery has proved to be the capacity of the vessel to receive oil, and the oil pumps have not been called upon to deliver at their full capacity.
Oil is handled by steam-driven pumps through pipes generally either 10 inches or 12 inches in diameter. A manifold is located outside the pump-house, consisting of 12-inch cast iron headers, valves and fittings to accomplish the following:
(a) The suction and discharge pipe of any pump in the handling plant can be connected with the pipe line to any tank in the tank farm. The manifold can be extended indefinitely to meet the further demands resulting from the construction of additional tanks.
(b) The manifold permits oil to be taken or delivered between the tank farm and three outlets at the water front simultaneously with or without the assistance of the pumps in the handling plant, as desired.
The Panama Canal purchases fuel oil under annual contract. The specifications fix the minimum flash point at 150° F., and the gravity between 16° and 240 Baume. Oil containing more than 2 per cent of water and sand is subject to a reduction in price for such excess, and in no case is oil containing more than 5 per cent acceptable.
The present price charged by the Panama Canal for fuel oil is as follows:
Per barrel
At Balboa $1.65
At Cristobal 1.90
For Diesel engine oil, the price is $2.50 per barrel.
For gasoline, the price charged ships is 20 ½ cents per gallon.
Docks and Piers
Permanent docks and piers of concrete and steel construction, completed or under construction, comprise the following, with length of berthing space approximately as stated:
Cristobal Lineal Feet
Commercial Pier No. 7....................................................................... 2450
Commercial Pier No. 8....................................................................... 2368
Commercial Dock No. 9 1150
Commercial Dock No.10 423
Coaling Pier No. 16............................................................................. 2588
Total................................................................................................... 8979
There is also a small boat binding of concrete between piers Nos. 8 and 9,410 feet long. In addition, an appropriation has been made for pier No. 6, with a berthing space of 2430 feet, which will give a total length of 11,839 feet, including the small boat landing, by the end of the calendar year 1918. Landings for tugs, launches, etc., will be constructed between piers Nos. 6 and 7, and between Nos. 7 and 8, having a total length of about 800 feet, as soon as the necessity for same develops.
Commercial docks and piers Nos. 7, 8, 9 and 10, and the small boat landing between Nos. 8 and 9, cost the Panama Railroad Company $3,450,000, or about $500 per lineal foot of berthing space. Dredging around the piers and docks cost $800,000, of which the Panama Railroad paid $300,000.
The depth of water referred to mean sea level alongside all permanent docks is 41 feet. The elevation of the floor of the docks above mean sea level varies from 10.2 to 11.5 feet. The average tidal range is 11 inches. In addition to the concrete and steel docks, there are a number of wooden docks and piers in Colon and Cristobal, which, while available for use at the present time, not being rat-proof, must, in accordance with health department regulations for the terminal ports, approved by the Governor, he removed before January 1, 1919, as on and after that date no docks, other than rat-proof docks, will be permitted in either Canal Zone or Panamanian waters at the canal terminals, in order to safeguard against the introduction and spread of bubonic plague.
At Colon, wooden piers Nos. 2, 3 and 4, have a berthing length of 2918 feet, with depth of water alongside from about 18 feet to 30 feet. Of these, Pier No. 3 is owned and used by the Royal Mail Steam Packet Company. Under its original franchise, the Panama Railroad was given control of all water frontage in Colon. In its early days the Panama Railroad disposed of two strips of water front to two steamship lines. The Pacific Mail Steamship Company succeeded to the title of one of these strips, which was re-purchased by the Panama Railroad Company in 1915, in order to carry out the policy adopted in 1913 for the control of all water frontage at the terminals by the Panama Canal or the Panama Railroad. Negotiations are under way similarly for the re-purchase by the Panama Railroad Company of the Royal Mail Steam Packet Company’s lot. When old piers Nos. 2, 3 and 4 at Colon are dismantled, the berthing of all vessels at the Atlantic terminal will be entirely and permanently transferred from Panamanian waters to Cristobal, in the canal zone.
In Cristobal there remain wooden docks Nos. 11, 13, 14 and 15, having a total length of 4011 feet, which will also be removed before 1919. These docks were all built during the canal construction period and are not in a good state of repair. The depth of water alongside varies from 25 feet to 35 feet, except at Dock No. 15, where the depth of water is from 15 to 20 feet.
There is also a piece of old wooden dock about 315 feet in length called the “angle dock” between the old French pier. Dock No. 4, and coal Dock No. 6, which will have to be replaced with permanent construction before 1919.
Docks Nos. 6, 7, 9, 13, 14, 15, 16, 17, 19, and Pier No. 18 cost approximately $3,650,000, or $465 per lineal foot of berthing space, of which the Panama Canal paid $3,500,000. In addition, the dredging of the inner basin, and around piers and docks, is costing $1,900,000 without the extension, which was recently appropriated for, of which the Panama Canal pays $1,650,000.
At Balboa are the following steel and concrete docks and piers:
| Lineal feet |
Reloading Coal Dock No. 6 | 745 |
Unloading Coal Dock No. 7 | 1052 |
Entrance Dock No.9 | 481 |
Repair Dock No. 13 | 290 |
Repair Dock No. 14 | 775 |
Commercial Dock No. 15 | 1146 |
Commercial Dock No.16 | 742 |
Commercial Pier No. 18 | 2201 |
Total | 7332 |
In addition are the following special docks of steel and concrete:
| Lineal feet |
Quarantine Landing Dock No. 1, for small boats | 60 |
Oil Crib “C” Dock No. 2, having a frontage of about 60 feet and a berthing length of about | 600 |
Old French Pier, Dock No. 4 (steel and concrete) | 1000 |
Small boat landings, Nos. 17 and 19, having a length of | 490 |
Total | 2150 |
At Balboa the depth of water in front of all docks and piers is 45 feet, referred to mean sea level, or 37.4 feet referred to mean low water, ordinary spring tides, except in front of Dock No. 1, the quarantine landing, where the depth of water is 20 feet, and in front of Dock No. 4, the old French pier, where the depth is 30 feet, although this depth can he readily increased to 45 feet when desired. The elevation of the deck of the docks above mean sea level varies from 16.5 feet to 17 feet, except for Dock No. 4, the old French pier, which has an elevation of 20.3 feet.
The deck or platform type of construction, with supports consisting of cylinders of concrete from six to eight feet in diameter, carried down to rock, has been followed for both docks and piers, in nearly all cases. The docks are tied back by steel anchors embedded in firm material. With piers, the lateral pressure of the earth was generally removed by dredging all material underneath to the full depth of the adjacent channel. This type of construction was adopted in preference to the more usual gravity type of quay wall, on account of the great depth to hard bottom—in some places as great as 125 feet—and the necessity of obtaining as great an amount of berthing space as possible with the funds available, and in the shortest time.
The platform of the docks and piers was generally constructed of steel floor beams and girders encased in concrete, with a deck slab of reinforced concrete. In some cases, where the conditions were suitable, the floor beams and girders were constructed of reinforced concrete. Most of the docks and piers are paved with vitrified brick, laid on edge. In nearly all cases a railroad track has been provided close to the water’s edge, and generally one or more tracks has been laid immediately back of the docks, and in the center of the piers. Where cargo is handled, these latter tracks fire usually “depressed.”
The commercial docks and piers are protected by sheds of steel and concrete, with tile roofs, one story in height, with large steel doors either of the rolling Kinnear type or the lifting Ogden type.
At Cristobal it is expected that practically all of the berthing space will be required for commercial use. At Balboa, docks Nos. 13 and 14 adjacent to the principal shops, having a length of about 1 (XX) feet, have been assigned for berthing vessels under repair. The remaining berthing space is available for commercial use, as may be necessary. There has always been considerable speculation on the isthmus as to the extent to which the Panama Canal would be justified in fitting up the commercial docks and piers with power appliances for the regular handling of cargo out of and into vessels. For unusually heavy lifts, either floating cranes or locomotive cranes will always be available. At Cristobal, along the outside of the dock and pier sheds, attachments for overhead blocks have been furnished by steel columns with a line of elevated longitudinal girders, to supplement the ships’ gear. At Balboa, where the extreme range of tides is 21.8 feet, the average west coast vessel is not equipped with long enough cargo booms to work its cargo at low stages of the tide. Dock No. 4, the old French pier, has an outfit: of twelve 4-ton electric cranes of the horizontal transporter type, and one pillar crane of 20 tons capacity. The shed of Pier No. 18 is provided with columns extending above the eaves, which support a line of elevated longitudinal girders for attaching blocks. At alternate columns there are also 65-foot booms on brackets 27.5 feet above the floor, having a capacity of three tons each and operated by portable electric winches. Electric 67 trucks, of one and two tons capacity, are used in considerable numbers on the docks at each terminal.
There has also been much conjecture, first, as to whether much freight would “break bulk” at the canal, and, second, which port would do the greatest amount of business of this character. The Panama Railroad ceased to be a factor in trans-isthmian transportation as regards through business with the opening of the canal, in line with the policy which is designed not to permit competition with the canal. The Panama Railroad, therefore, became a passenger line except for the carrying of local, canal and commercial freight. With the cessation of the shipment of through freight across the isthmus by rail, it became necessary at first for the Panama Railroad Steamship Line to run its vessels through the canal to Balboa to reduce the accumulation of freight at the terminals. Within a short time, arrangements were made by west coast steamship lines, including the South American Steamship Company, the Peruvian Steamship Line, and the Pacific Steam Navigation Company, so that their vessels go through the canal and make Cristobal a terminal port, thus doing away with the necessity of the Panama Railroad steamers transiting the canal. This has made Cristobal the most important commercial terminal, and it seems fair to assume that Balboa’s importance as a commercial terminal for the transfer of cargo will always remain secondary to Cristobal. This result works out very well with the policy of equipping Balboa with the principal facilities for dry-docking and repairing vessels, hut may necessitate a considerable extension of the present docking and repair facilities at Cristobal.
The general layout of each terminal provides room for the construction of two additional piers at Cristobal, Nos. 4 and 5, behind the mole; and the construction of four additional piers at the head of the inner basin extended, at Balboa, should the future growth of canal traffic render their construction necessary. There will undoubtedly be improvements and additions to the terminals required for a number of years to come to keep pace with the growing requirements. At Ralboa, it is believed that the early completion of Dry Dock No. 2, the cost of which is comparatively small, will be found desirable, and that the location and design of a permanent repair and dry dock plant at the Atlantic terminal is a project that will have to be given attention in the near future.
The deferring of the planning and construction of the canal terminals until comparatively late in the canal construction period, and after matters of general policy and of canal requirements had rounded into definite shape, has proved advantageous, as it has- permitted the symmetrical construction at one time of the entire plant, and has secured terminals which meet present needs and are readily capable of expansion to meet any future requirements.