HITHERTO unavailable documents relating to the very earliest days of our Navy must contain much that is of interest, and the recently initiated gradual publication of this material should bring to light many an incident to fortify our service traditions and to preserve for posterity much ancient lore of those days of sail that are fast fading from national memory.
In the first volume of these papers, just issued by the Office of Naval Records and Library, appears what is, so far as this writer’s observation extends, the earliest known report of the use of a method of search based on the principles of the “retiring search curve” of War College fame.
In an extract from the journal of Captain Thomas Truxtun of the U. S. frigate Constellation, under date of August 13, 1798, appears the following entry. The ship’s position is given as 11 leagues east of Cape Henry.
Moderate breezes, and a swell from the Southward ... At 6 p.m. saw a Sail in the South East (standing to the Northward) at a great Distance from the Masthead, gave chace and at 7 Ditto, it being dark, lost Sight of her, and in order to fall in with her again in the Morning, I observed the following Plan. Having previously observed her sailing, as we only altered her Bearing one Point of the Compass from the Time she was first discovered to our losing Sight of her. As soon as it was dark, I kept the Ship away North East, untill I run seven Miles, then hawled up East North East, and run in that Direction four Miles, then Hawled up East, and run four Miles, making on these three angles fifteen Miles; I then bore away North by Compass, and a 4 a.m. it being Dawn of Day, after having run on that Course six Miles, she was discovered bearing about North B. West, one Quarter of a Mile Distance, at 5 ditto brought her to with a Shot.
Disregarding variation of the compass, and making due allowance for leeway, the tracks of the Constellation and her “Chace” as reconstructed from the above data, could not have been far from those shown in the accompanying sketch.
Certain assumptions must be made, which can be justified from known conditions. The distance of the “Sail in the South East” at a “great Distance from the Mast Head” was probably fully 36,000 yards. The Constellation’s fore-topmast head was high enough to give a visible sea horizon of all of 11 or 12 miles, and a royal yard would have added considerable to this. The sails of the “Chace,” which turned out to be the American schooner Polly, would have added several more miles. Eighteen miles is not too far to assume as effective visibility, away from the sun, for a Southern Drill Ground late summer afternoon.
The wind could not have been much east of south. The Constellation was a notoriously fine sailer (the writer vividly remembers, as a small boy, watching her work handily in and out of New London Harbor in her last years as a practice cruise ship, nearly a century after the incident under discussion). But even so, for her to lay a course east would mean a breeze around south by east or at most south-southeast. Reference to “keeping away” northeast, “hawling up East” and “Bore away North” verify this conclusion, and also make it probable that east was the approximate course during the hour from “6 p.m. to 7 Ditto” not definitely logged in the above quotation from Captain Truxtun’s journal.
It is of interest to approximate also the distance covered during this time. The recorded run of 21 miles in the 9 hours of darkness figures an average speed of 2.3 knots. Of the distance covered, 13 miles was running free and before the wind, presumably at a greater speed than the two legs close-hauled. A fair proportioning of speeds under the differing conditions gives a run for the hour of dusk of about 1.8 miles.
Plotting this with use of the given bearing and estimated distance of the Polly
[FIGURE]
results in the indicated positions for both ships at the start of the chase, which cannot be far wrong.
The data for the movements of the schooner are scanty; her positions and run as plotted are consistent with what is recorded and with the probable wind. Her average speed figures out to about 3 knots. She is said to have “Only altered her Bearing one Point of the Compass” during the hour she was under observation. As she was running free while the Constellation was close-hauled, she must have been the faster moving of the two, and her bearing must have altered to the left. As plotted, the change in bearing shows nearer one-half point than one point, but considering the crudity of the methods of taking bearings of those days, and the probability that all observations of the schooner were taken from the masthead, the co-ordination is close enough.
It is interesting to speculate as to how close the two vessels came during the night. If the plotted tracks are anywhere near correct, the Polly must have crossed within 2 miles ahead of the Constellation just before the latter made her final change of course to north, somewhere around half-past two.
Captain Truxtun did not have the modem scientific name for the “Plan that he observed,” but he must have experienced quite a glow of satisfaction as he made out the sails of his quarry looming up close aboard in the early twilight and gave the order for a gun to be prepared to bring her to.