[undecipherable] A P P E N D I X. [Joseph Fox] S I R, Philadelphia, June 23^d, 1794. As I consider the masting of our frigates as of the utmost importance to their sailing, working, and general ease and management at sea, I have herewith annexed proportions calculated from a system I formed some years ago; and although I believe these proportions would be approved of by [strikethrough: com-] [strikethrough: cent judges of the subject, — —] I wish the most experienced sea-officers of skill here, or other ingenious persons, who have been at sea, to be consulted before they are adopted: I mention sea-officers, &c. because it is almost impossible that any other description of men, who have not had an opportunity of being often at sea, can form a proper judgment on this important subject; as the complete masting of a ship must be guided by nice observation, experience, and judgment, accompanied with some degree of philosophy. I have the honour to be, S I R, Your most obedient (Copy.) And very humble servant, THOMAS TRUXTUN. [Secretary of War, &c. &c.] ii A P P E N D I X. R E M A R K S. As the extreme breadth of beam of a ship is proportioned to the length of her keel, so are the length of her masts and yards calculated to that breadth; but as the formation of all vessels' bodies differ according to the purpose for which they are intended, it is absolutely necessary to vary in the mode of calculating the dimensions of the spars, according to the construction of the body. The diameter of all spars here, under the denomination of masts, are [strikethrough: attached to] be one inch in the partners to every three feet in length; and that of the yards one inch in the slings to four and three quarters feet of the whole length, the mizen-mast excepted, which from its being made the same length of the fore-mast, on account of carrying a large boom, mizen, or spanker, the size is reduced to one inch in the partners, to every four feet of the whole length; and the bow-sprit in the bed is fixed of the same size as the foremast in the partners. In calculating the diameter of pole-masts, such as a pole mizen-top-mast, or pole top-gallant-mast, the length of the pole is deducted, and the remainder being the length of the mast from the heel to the hound, is divided by three, to give its diameter in inches in the cap. As the breadth of beam, length of main-mast and main-yard, is here given as the basis of all proportions for the other spars, to find the length of the main-mast I take twice the breadth of the beam, and one-sixth of the sum, and add them together; and to find the length of the main yard, I take twice the breadth of the beam. The studding-sail booms and yards, &c. not mentioned here, are calculated and regulated by the usual mode. The same principle of masting will answer for ships of the line, only with them a respect must be had to their additional depth. A P P E N D I X. iii *Here follows the calculation of the masts, yards, and spars of a Frigate of 44 guns, of the following dimensions, viz.* 145 feet keel, straight rabbet; extreme breadth of beam 43 feet 6 inches; depth of hold 14 feet 3 inches; depth between decks 6 feet 3 inches; and the waist 7 feet; otherwise in proportion. Extreme breadth of beam - Feet 43 6 Multiply by - - 2 —— This the length of the main-yard - 87 Add one-sixth of this sum - - 14 6 —— The length of main-mast - - 101 6 A P P E N D I X. General proportions of *Masts, Spars, &c.* for a Frigate built for War of 44 guns. [Table: columns — Feet | [undecipherable] | Poles | Head r[undecipherable] | Diam. i[undecipherable] | Arms out of [undecipherable] | Head | Diameter] Main-mast the whole length [see calculated p.3] 101 6 [undecipherable] [undecipherable] One thirteenth deduct from the main-mast; and the remainder is the whole length of its fore-mast [undecipherable] [undecipherable] [undecipherable] Mizen-mast the same length of the fore-mast [undecipherable] [undecipherable] [undecipherable] Main-yard the whole length [see p.3] 87 [undecipherable] [undecipherable] Cross-jack yard one-quarter shorter than the fore-yard [undecipherable] [undecipherable] [undecipherable] Bow-sprit one-quarter shorter than the fore-mast [undecipherable] [undecipherable] [undecipherable] Jib-boom one-quarter [undecipherable] [undecipherable] [undecipherable] [undecipherable] Three-fifths the length of the main-mast is the main-top-mast [undecipherable] [undecipherable] [undecipherable] One-seventh deduct from the main-top-mast, and the remainder is the fore-top-mast [undecipherable] [undecipherable] [undecipherable] Two-thirds of the [undecipherable] is the mizen-top-mast [undecipherable] [undecipherable] [undecipherable] Four-fifths of the main-top-mast is the main-top-gallant-mast [undecipherable] [undecipherable] [undecipherable] Difference between [undecipherable] gives the fore-top-gallant-mast [undecipherable] [undecipherable] [undecipherable] Difference between the clued and reef, taken from the fore-yard, gives the main-top-sail-yard [undecipherable] [undecipherable] [undecipherable] Difference between [undecipherable] taken from the fore-yard, gives the fore-top-sail-yard [undecipherable] [undecipherable] [undecipherable] Difference between [undecipherable] gives the fore-top-gallant-yard [undecipherable] [undecipherable] [undecipherable] Difference between [undecipherable] gives the mizen-top-gallant-yard [undecipherable] [undecipherable] [undecipherable] Mizen, or [undecipherable], the length of the [undecipherable] [undecipherable] [undecipherable] [undecipherable] Mizen or [undecipherable] yard, do. [undecipherable] [undecipherable] [undecipherable] Mizen-top-gallant-yard, do. [undecipherable] [undecipherable] [undecipherable] Spanker-boom one-[undecipherable] and a [undecipherable] the breadth of the beam in midships [undecipherable] [undecipherable] [undecipherable] Gaff [undecipherable] [undecipherable] [undecipherable] [undecipherable] No. [undecipherable] [undecipherable] [undecipherable] [undecipherable] The sprit-sail-yard the same as the fore-top-sail yard, and the sprit-sail-top-sail-yard the same as [undecipherable] is illustrated. A P P E N D I X. DIMENSIONS of the *Masts, Yards, and Spars* of a Frigate of 36 guns — whole length of keel u 136 feet — extreme breadth of beam 36 feet — depth of hold 13 feet — depth between decks 6 feet — and waist 6 feet 6 inches, and otherwise in proportion: calculated from the principles laid down in the foregoing sheets. [Table: columns — Feet | [undecipherable] | Poles | Head | Diam.] Main-mast the whole length [undecipherable] [undecipherable] [undecipherable] Fore-mast do. [undecipherable] [undecipherable] [undecipherable] Mizen-mast do. [undecipherable] [undecipherable] [undecipherable] Main yard do. [undecipherable] [undecipherable] [undecipherable] Cross-jack yard do. [undecipherable] [undecipherable] [undecipherable] Bow-sprit do. [undecipherable] [undecipherable] [undecipherable] Jib-boom do. [undecipherable] [undecipherable] [undecipherable] Main-top-mast [undecipherable] [undecipherable] [undecipherable] Mizen-top-mast do. [undecipherable] [undecipherable] [undecipherable] Fore-top-mast [undecipherable] [undecipherable] [undecipherable] Main-top-gallant-mast do. [undecipherable] [undecipherable] [undecipherable] Fore-top-gallant-mast do. [undecipherable] [undecipherable] [undecipherable] Mizen-top-gallant-mast do. [undecipherable] [undecipherable] [undecipherable] Main-top-sail-yard do. [undecipherable] [undecipherable] [undecipherable] Fore-top-sail-yard do. [undecipherable] [undecipherable] [undecipherable] [undecipherable]-gallant-yard do. [undecipherable] [undecipherable] [undecipherable] Mizen-top-gallant-yard do. [undecipherable] [undecipherable] [undecipherable] Main-top-gallant-yard do. [undecipherable] [undecipherable] [undecipherable] Fore-top-gallant-yard do. [undecipherable] [undecipherable] [undecipherable] Spanker-boom do. [undecipherable] [undecipherable] [undecipherable] Gaff [undecipherable] do. [undecipherable] [undecipherable] [undecipherable] Do, mizen do. [undecipherable] [undecipherable] [undecipherable] No. [undecipherable] do. [undecipherable] [undecipherable] [undecipherable] N.B. I have observed before, that it is necessary to vary the size and dimensions of masts, according to the formation of the body, as the purpose the ship is intended for. And I may add also, that in merchant-ships, according to the number of hands to be employed on board them, in any particular service. The foregoing calculation being intended only for ships constructed and built for war, the maker may easily make the necessary variations for other vessels. In forming this system of masting, I have made the extreme breadth of beam the basis of calculation, as it is by the breadth of beam that we are to measure and judge what quantity of weight and pressure a ship will bear, from her cargo, and rigged aloft, without inclining, so as to drag a part of her upper works in the water; for if a ship from this or any other cause, does not stand upright, the [undecipherable] has taken so much pains to construct, and its dimension destroyed. viii A P P E N D I X. One proportion (the breadth of beam) of the hull being taken to find the length of the main-mast and main-yard, as I have shown, another part may as properly be taken to proportion the mast-heads, &c. I have therefore brought forward the depth of waist, and the depth between decks for this purpose; which I think will answer as a better proportion than one-fourth of the length of the top-mast: for it must be observed, that there are inconveniences attending mast-heads, being too long as well as their being too short. However, if one-fourth of the whole length of the top-mast, as I have before mentioned, is taken for the lower masts heads, it will make but little difference from the first method; as per example. By the first method, the 44 gun ships' main and fore-mast heads are 13 feet 4 inches, (as the agitation of the fore-mast is greater than the main-mast, I have fixed the fore-mast head to be of the same length as the main-mast head), and by the second method, the main-mast head would be 15 feet 2 inches and a quarter; difference 22 inches and a quarter; and the fore-mast head 14 feet 5 inches; difference from the first method 13 inches. The pole-mizen-top-mast the whole length is 62 feet 4 inches. I deduct the pole 21 feet therefrom, and the remainder being 41 feet 4 inches, is the length of the mizen-top-mast, from heel to hound; one-fourth of which is 10 feet 4 inches, for the head of the mizen-mast; and by the first method, the head of the mizen-mast is 10 feet; difference 4 inches. The pole main-top-gallant-mast the whole length is 48 feet 8 inches. I deduct the pole 16 feet, and the remainder being 32 feet 8 inches, is the length of the main-top-gallant-mast, from heel to hound; one-fourth of which is 8 feet 2 inches, for the head of the main-top-mast; and by the first method, the head of the main-top-mast is 8 feet; difference 2 inches only. The fore-top-mast head calculated in the same way, would give but little difference also from the first method. In fact, either of these methods of finding the lengths of mast-heads will answer very well, as their difference is too trifling to be of any consequence. The only true way of masting a ship, is by her own dimensions, and not at random, as merchantmen mostly are: and with respect to yards, I am clearly of opinion, that the ships of war of all nations carry too square yards, for the following reason: 1st, Where a ship of this sort is going by the wind, and her yards braced up, you will find in general that the after part of her sails becomes a back sail; consequently instead