according to the fashion of a ship, or in the manner of an expert sailer; as, The mast is not rigged ship-shape; Trim your sails ship-shape.

STOWING AND TRIMMING OF SHIPS, the method of disposing of the cargo in a proper and judicious manner in the hold of a ship.

A ship's sailing, steering, staying, and wearing, and being lively and comparatively easy at sea in a storm, depends greatly on the cargo, ballast, or other materials, being properly stowed, according to their weight and bulk, and the proportional dimensions of the built of the ship, which may be made too crank or too stiff to pass on the ocean with safety. These things render this branch of knowledge of such consequence, that rules for it ought to be endeavoured after, if but to prevent, as much as possible, the danger of a ship over-filling at sea, or being so labourfome as to roll away her masts, &c. by being improperly stowed, which is often the case.

When a ship is new, it is prudent to consult the builder, who may be supposed best acquainted with a ship of his own planning, and most likely to judge what her properties will be, to advise how the cargo or materials, according to the nature of them, ought to be disposed of to advantage, so as to put her in the best sailing trim; and at every favourable opportunity afterwards it will be proper to endeavour to find out her best trim by experiment.

Ships must differ in their form and proportional dimensions; and to make them answer their different purposes, they will require different management in the flowage, which ought not to be left to mere chance, or done at random, as goods or materials happen to come to hand, which is too often the cause that such improper flowage makes ships unfit for sea: therefore the flowage should be considered, planned, and contrived, according to the built and properties of the ship, which if they are not known should be inquired after. If she is narrow and high-built in proportion, so that she will not shift herself without a great weight in the hold, it is a certain sign such a ship will require a great part of heavy goods, ballast, or materials, laid low in the hold, to make her stiff enough to bear sufficient sail without being in danger of over-filling. But if a ship be built broad and low in proportion, so that she is stiff and will support herself without any weight in the hold, such a ship will require heavy goods, ballast, or materials, stowed higher up, to prevent her from being too stiff and labourfome at sea, so as to endanger her masts being rolled away, and the hull worked loose and made leaky.

In order to help a ship's sailing, that she should be lively and easy in her pitching and ascending motions, it should be contrived by the flowage, that the principal and weightiest part of the cargo or materials should lie as near the main body of the ship, and as far from the extreme ends, fore and aft, as things will admit of. For it should be considered, that the roomy part of our ships lengthwise forms a sweep or curve near four times as long as they are broad; therefore those roomy parts at and above the water's edge, which are made by a full harping and a broad transom to support the ship steady and keep her from plunging into the sea, and also by the entrance and run of the ship having little or no bearing body under for the pressure of the water to support them, of course should not be flowed with heavy goods or materials, but all the necessary vacancies, broken flowage, or light goods, should be at these extreme ends fore and aft; and in proportion as they are kept lighter by the flowage, the ship will be more lively to fall and rise easy in great seas; and this will contribute greatly to her working and failing, and to prevent her from straining and hogging; for which reason it is a wrong practice to leave such a large vacancy in the main hatchway, as is usual, to coil and work the cables, which ought to be in the fore or after hatchway, that the principal weight may be more easily flowed in the main body of the ship, above the flatteft and lowest floorings, where the pressure of the water acts the more to support it.

Machine for measuring a Ship's Way. We have already described a variety of machines or instruments which have been proposed for this purpose under the article Log. In this place, therefore, we shall confine ourselves to the machine invented by Francis Hopkinson, Esq., Judge of the Admiralty in Pennsylvania.—After having shown the fallacies to which the common log, and also that particular kind of instrument invented by M. Saumarez, are liable, he proceeds to describe his own machine as follows:

This machine, in its most simple form, is represented by fig. 5, Plate CCCCLIII., wherein A B is a strong rod of iron moveable on the fulcrum C. D is a thin circular palate of brass riveted to the lower extremity of the rod. E an horizontal arm connected at one end with the top of the rod A B by a moveable joint F, and at the other end with the bottom of the index H, by a like moveable joint G. H is the index turning on its centre I, and travelling over the graduated arch K; and L is a strong spring, bearing against the rod A B, and constantly counteracting the pressure upon the palate D. The rod A B should be applied close to the cut-water or stem, and should be of such a length that the palate D may be no higher above the keel than is necessary to secure it from injury when the vessel is aground, or fails in shoal water. As the bow of the ship curves inward towards the keel M, the palate D will be thrown to a distance from the bottom of the vessel, although the perpendicular rod to which it is annexed lies close to the bow above; and therefore the palate will be more fairly acted upon. The arm E should enter the bow somewhere near the hawse hole, and lead to any convenient place in the forecastle, where a smooth board or plate may be fixed, having the index H, and graduated arch K, upon it.

It is evident from the figure, that as the ship is urged forward by the wind, the palate D will be pressed upon by the resisting medium, with a greater or less force, according to the progressive motion of the ship; and this will operate upon the levers so as to immediately affect the index, making the least increase or diminution of the ship's way visible on the graduated arch; the spring L always counteracting the pressure upon the palate, and bringing back the index, on any relaxation of the force impressed.

This machine is advantageously placed at the bow of the ship, where the current first begins, and acts fairly upon the palate, in preference to the stern, where the tumultuous closing of the waters causes a wake, visible to a great distance. The palate D is sunk nearly as low as the keel, that it may not be influenced by the heaping up of the water and the dashing of the waves at and near the water line. The arch K is to ascertain how many knots or miles she would run in one hour at her then rate of sailing. But the graduations on this arch must be unequal; because the resistance of the spring L will increase as it becomes more bent, so that the index will travel over a greater space from one to five miles than from five to twelve. Lastly, the palate, rod, spring, and all the metallic parts of the instrument, should be covered with a strong varnish, to prevent rust from the corrosive quality of the salt water and sea air.

This machine may be considerably improved as follows: Let the rod or spear A B (fig. 5,) be a round rod of iron or steel, and instead of moving on the fulcrum or joint, as at C, let it pass through and turn freely in a socket, to which socket the moveable joint must be annexed, as represented in fig. 6. The rod must have a shoulder to bear on the upper edge of the socket, to prevent its slipping quite down. The rod must also pass through a like socket at F, fig. 5. The joint of the lower socket must be fixed to the bow of the ship, and the upper joint or socket must be connected with the horizontal arm E. On the top of the uppermost socket let there be a small circular plate, bearing the 32 points of the mariner's compass; and let the top of the rod A B come through the centre of this plate, so as to carry a small index upon it, as is represented in fig. 7. This small index must be fixed to the top of the rod on a square, so that by turning the index round the plate, the rod may also turn in the sockets, and of course carry the palate D round with it; the little index always pointing in a direction with the face of the palate. The small compass plate should not be fastened to the top of the socket, but only fitted tightly on, that it may be moveable at pleasure. Suppose then the intended port to bear S. W. from the place of departure, the palate must be turned on the socket till the fourth-west point thereof looks directly to the ship's bow; so that the fourth-west and north-east line on the compass plate may be precisely parallel with the ship's keel, and in this position the plate must remain during the whole voyage. Suppose, then, the ship to be sailing in the direct course of her intended voyage, with her bowprit pointing fourth-west. Let the little index be brought to the fourth-west point on the compass plate, and the palate D will necessarily present its broad face toward the port of destination; and this it must always be made to do, be the ship's course what it may. If, on account of unfavourable winds, the ship is obliged to deviate from her intended course, the little index must be moved so many points from the fourth-west line. One of the compass plate as the compass in the binnacle shall show that she deviates from her true course; so that in whatever direction the ship shall fail, the palate D will always look full to the south-west point of the horizon, or towards the port of destination, and consequently will present only an oblique surface to the resisting medium, more or less oblique as the ship deviates more or less from the true course of her voyage. As, therefore, the resistance of the water will operate less upon the palate in an oblique than in a direct position, in exact proportion to its obliquity, the index H will not show how many knots the vessel runs in her true course, but will indicate how many she gains in the direct line of her intended voyage—Thus, in fig. 9, if the ship's course lies in the direction of the line AB, but she can fail by the wind no nearer than AC; suppose, then, her progressive motion such as to perform AC equal to five knots or miles in an hour, yet the index H will only point to four knots on the graduated arch, because she gains no more than at that rate on the true line of her voyage, viz., from A to B. Thus will the difference between her real motion and that pointed out by the index be always in proportion to her deviation from her intended port, until she fails in a line at right angles therewith, as AD; in which case the palate would present only a thin sharp edge to the resisting medium, the pressure of which should not be sufficient to overcome the friction of the machine and the bearing of the spring L. So that at whatever rate the ship may fail on that line, yet the index will not be affected, showing that she gains nothing on her true course. In this case, and also when the vessel is not under way, the action of the spring L should cause the index to point at O, as represented by the dotted lines in fig. 5. and 8.

As the truth of this instrument must depend on the equal pressure of the resisting medium upon the palate D, according to the ship's velocity, and the proportionate action of the spring L, there should be a pin or screw at the joints C and F, so that the rod may be readily unslipped and taken in, in order to clean the palate from any fouling it may contract, which would greatly increase its operation on the index H, and thereby render the graduated arch false and uncertain.

Further, the spring L may be exposed too much to injury from the salt water, if fixed on the outside of the ship's bow. To remedy this, it may be brought under cover, by constructing the machine as represented by fig. 8, where AB is the rod, C the fulcrum or centre of its motion, D the palate, E the horizontal arm leading through a small hole into the forecastle; M is a strong chain fastened at one end to the arm E, and at the other to a rim or barrel on the wheel G, which by means of its teeth gives motion to the semicircle I and index H. The spring L is spiral, and enclosed in a box or barrel, like the main spring of a watch. A small chain is fixed to, and passing round the barrel, is fastened by the other end to the fusee W. This fusee is connected by its teeth with the wheel G, and counteracts the motion of the palate D. N, N, are the two sockets through which the rod AB passes, and in which it is turned round by means of the little index R. S is the small compass plate, moveable on the top of the upper socket N. The plate S hath an upright rim round its edge, cut into teeth or notches, so that when the index R is a little raised up, in order to bring it round to any intended point, it may fall into one of these notches, and be detained there; otherwise the pressure of the water will force the palate D from its oblique position, and turn the rod and index round to the direction in which the ship shall be then failing.—Should it be apprehended that the palate D, being placed so far forward, may affect the ship's steerage, or obstruct her rate of failing, it should be considered that a very small plate will be sufficient to work the machine, as one of three or four inches in diameter would probably be sufficient, and yet not large enough to have any sensible effect on the helm or ship's way.

The greatest difficulty, perhaps, will be in graduating the arch K, (if the machine is constructed as in fig. 5.), the unequal divisions of which can only be ascertained by actual experiment on board of each ship respectively, inasmuch as the accuracy of these graduations will depend on three circumstances, viz. the position of the fulcrum C with respect to the length of the rod, the size of the palate D, and the strength or bearing of the spring L. When these graduations, however, are once ascertained for the machine on board of any one vessel, they will not want any future alterations, provided the palate D be kept clean, and the spring L retains its elasticity.

But the unequal divisions of the graduated arch will be unnecessary, if the machine is constructed as in fig. 8.; for as the chain goes round the barrel L, and then winds through the spiral channel of the fusee W, the force of the main spring must operate equally, or nearly so, in all positions of the index, and consequently the divisions of the arch K may in such case be equal.

After all, it is not expected that a ship's longitude can be determined to a mathematical certainty by this instrument. The irregular motions and impulses to which a ship is continually exposed, make such an accuracy unattainable perhaps by any machinery: But if it should be found, as we flatter ourselves it will on fair experiment, that it answers the purpose much better than the common log, it may be considered as an acquisition to the art of navigation.

It should be observed, that in ascertaining a ship's longitude by a time-piece, this great inconvenience occurs, that a small and trifling mistake in the time makes a very great and dangerous error in the distance run: Whereas the errors of this machine will operate no farther than their real amount; which can never be great or dangerous, if corrected by the usual observations made by mariners for correcting the common log.

A like machine, made in its simple form (as at fig. 5.), so constructed as to ship and unship, might occasionally be applied alongside about midships, in order to ascertain the leeway; which, if rightly shown, will give the ship's precise longitude. As to sea currents, this and all other machines hitherto invented must be subject to their influence; and proper allowances must be made according to the skill and knowledge of the navigator.

Lastly, some discretion will be necessary in taking observations from the machine to be entered on the log-book: that is, the most favourable and equitable moment should be chosen for the observation; not whilst the ship is rapidly descending the declivity of a wave, or is suddenly checked by a stroke of the sea, or is in the very act of plunging. In all cases, periods may be found in which a ship proceeds with a true average velocity;