SHIP-Money, was an imposition charged upon the ports, towns, cities, boroughs, and counties of this realm, in the reign of King Charles I. by writ, commonly called bip-writs, under the great seal of England, in the years 1635 and 1636, for the providing and furnishing of certain ships for the king's service, &c. which was declared to be contrary to the laws and statutes of this realm, the petition of right and liberty of the subject, by Stat. 17 Car. I. c. 14. See Blackstone's Commentaries, vol. iv. p. 30.
SHIP-Shape, 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 overfetting at sea, or being so laboursome 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 stowage, 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 stowage makes ships unfit for sea: therefore the stowage 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 overfetting. 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 laboursome 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 stowage, 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 haring 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 prelude of the water to support them, of course should not be flowed with heavy goods or materials, but all the necessary vacancies, broken stowage, or light goods, should be at these extreme ends fore and aft; and in proportion as they are kept lighter by the stowage, the ship will be more lively to fall and rise easy in great seas; and this will contribute greatly to her working and sailing, 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 stowed in the main body of the ship, above the flattest and lowest floorings, where the prelude of the water acts the more to support it.
Improved Capstan of SHIPS.—A capstan has been contrived by Mr Bofwell, which works without requiring the messenger or cable coiled around it, to be ever surged; an operation which is necessary with common capstans, and is always attended with delay, and frequently with danger. This capstan has been approved by some gentlemen connected with the British navy. A model of this machine was presented to the Society for the Encouragement of Arts, and Mr Bofwell received the gold medal of the society for his invention *.
For the information of those unacquainted with maritime affairs, Mr Bofwell gives an account of the manner in which cables are hauled on board of large ships. For the purpose of shewing the advantage of his improved capstan, cables, he observes, above a certain diameter are too inflexible to admit of being coiled round a capstan; in ships where cables of such large dimensions are necessary, a smaller cable is employed for this purpose, which is called the messenger, the two ends of which are made fast together so as to form an endless rope, which, as the capstan is turned about, rolls round it in unceasing succession, passing on its course to the head of the ship, and again returning to the capstan. To this returning part of the messenger, the great cable is made fast by a number of small ropes called nippers, placed at regular intervals; these nippers are applied, as the cable enters the hawse hole, and are again removed as it approaches the capstan, after which it is lowered into the cable tier.
The messenger, or any other rope coiled round the capstan, must descend a space at every revolution equal to the diameter of the rope or cable used; this circum-
* Transf. to 1807. Phil Mag. xxii. 297. stance brings the coils in a few turns to the bottom of the capstan, when it can no longer be turned round, till the coils are looened and raised up to its other extremity, after which the motion proceeds as before. This operation of shifting the place of the coils of the messenger on the capstan is called surging the messenger. It always causes considerable delay; and when the messenger chances to slip in changing its position, which sometimes happens, no small danger is incurred by those who are employed about the capstan.
One method of preventing the necessity of surging, by placing a horizontal roller beneath the messenger when it first enters on the capstan, adds considerably to the labour in turning the capstan, and the great friction which the messenger must suffer, must occasion a very great wear and injury to the messenger.
Another method to prevent surging was, that for which Mr Plucknet obtained a patent. In this way a number of upright lifters, placed round the capstan, were made to rise in succession as the capstan turned round by a circular inclined plane placed beneath them; a method Mr Bofwell thinks superior to the former; but still the wear of the messenger from the lateral friction in rising against the whelps of the capstan remains undiminished.
A third method proposed by Captain Hamilton, left the lateral friction, and wear of the messenger against the whelps of the capstan, as great as in the others, having also the inconvenience of causing the coils to become loose as they ascend, the upper part of the barrel being nearly one third less in the diameter than the lower part.
In Mr Bofwell's method of preventing the necessity of surging, none of the lateral friction of the messenger or cable against the whelps of the capstan, can possibly take place, and of course the wear of the messenger occasioned thereby will be entirely avoided, while it performs its purpose with a less moving power than any of them.
His method consists in the simple addition of a second smaller barrel or capstan of less dimensions to the large one; beside which it is to be placed in a similar manner, and which need not in general exceed the size of a half barrel cask. The coils of the messenger are to be passed alternately round the large capstan and this small barrel, but with their direction reversed in the different barrels, so that they may cross each other in the intervals between the barrels, in order to have the more extensive contact with, and better grip on each barrel. To keep the coils distinct, and prevent their touching each other in passing from one barrel to the other, projecting rings are fastened round each barrel at a distance from each other equal to about two diameters of the messenger, and the thickness of the ring. Those rings should be so fixed on the two barrels that those on one barrel should be exactly opposite the middle of the intervals between those on the other barrel; the only circumstance which requires particular attention in the construction of this capstan. The rings should project about as much as the messenger from the barrels, which may be formed with whelps, and in every other respect, not before mentioned, in the usual manner for capstan barrels. The small barrel should be furnished with falling palls as well as the large one; a fixed iron spindle ascending from the deck will be the best for it, as it will take up less room. The spindle may be secured below the deck, so as to bear any strain, as the small barrel need not be much above half the height of the large barrel; the capstan bars can easily pass over it in heaving round, when it is thought fit to use capstan bars on the same deck with the small barrel. As two turns of the messenger round both barrels will be at least equivalent to three turns round the common capstan, it will scarcely ever be necessary to use more than four turns round the two barrels.
That which prevents the lateral friction of the messenger in Mr Bofwell's double capstan is, that in it each coil is kept distinct from the rest, and must pass on to the second barrel before it can gain the next elevation on the first, by which no one coil can have any influence in raising or depressing another; and what each separate coil defends in a single revolution it regains as much as is necessary in its passage between the barrels when in the air, and free from all contact with any part of the apparatus, it attains a higher elevation without a possibility of friction or wear.
It is equally applicable in large and in smaller vessels, in the former of which messengers are necessary, from the size of the cables; but in the latter also, where cables can be managed with the same ease as messengers. The same principle may be also easily applied to windlasses, by having a small horizontal barrel placed parallel to the body of the windlass, and having both fitted with rings in the same way as is proposed for the capstan. The place for the small horizontal barrel is forward, just before the windlass, and it should also be furnished with catch polls.
Besides the advantages now stated, the improved capstan is simple in its construction, can be fitted up at small expense, is easily repaired, and requires but little room.
A represents the common capstan; B, another of smaller dimensions; C, the coils of the messenger passing alternately round the large and small capstans, but with the direction reversed on the different barrels, so that they may cross each other in the interval between them; DDDD, are projecting rings round each barrel, so fixed on the two barrels, that those on one barrel should be exactly opposite the middle of the intervals between those on the other barrel.
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.—Transactions of the American Philosophical Society, vol. III. p. 160.
This machine, in its most simple form, is represented by fig. 5, wherein AB 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 a horizontal arm connected at one end with the top of the rod AB 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 AB, and constantly counteracting the pressure upon the palate D. The rod AB 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 flood 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 water 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 AB (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 AB 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 south-west point therein looks directly to the ship's bow; so that the south-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 failing in the direct course of her intended voyage, with her bowprit pointing south-west. Let the little index be brought to the south-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 south-west line 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 then 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 sail 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 falls 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 sail 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 proportionable 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 unshipped and taken in, in order to clean the palate from any foulness 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 fuze W. This fuze 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 too far forward, may affect the ship's steerage, or obstruct her rate of falling, 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 fuze 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 shewn, 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; to discover which, a little experience and attention will lead the skilful mariner.
It has been observed of the machine now described, that an ingenious mechanic would probably construct it to better advantage in many respects. The author only meant to suggest the principle; experiment alone can point out the best method of applying it. He is sensible of at least one deficiency, viz. that the little index R, fig. 4, will not be strong enough to retain the palate D in an oblique position when the ship is falling by the wind; more especially as the compass plate S, in whose notched rim the index R is to fall, is not fixed to, but only fitted tight on the socket N. Many means, however, might be contrived to remedy this inconvenience.
SHIP-Wreck. A French author has lately proposed some methods of saving the lives of persons shipwrecked near the coast. He observes, that the most proper means for saving the crews of shipwrecked vessels is, to establish a rope of communication from them to the shore. To a bomb or cannon ball should be fastened the end of a rope, extended afterwards in a zig-zag direction before the mortar or cannon, or suspended on a piece of wood raised several feet. But as it was necessary to know if the cord would not break by the force of the explosion and the velocity of the motion, the author thought it proper to consult professional men. He accordingly wrote to some officers of the artillery in garrison at La Fere in France, and they almost all replied that the rope would infallibly break.
Not deeming this answer satisfactory, he happily conceived the idea of making the experiment on a small scale. He cauled a piece of the barrel of a musket to be filed into the form of a small mortar of 18 lines in length internally; and having tied a packthread to a common ball of lead, he made an experiment which perfectly succeeded, as did many others which he afterwards repeated, even with the strongest charges of powder. This success he communicated to the officers of artillery, who replied, that there was a great difference between a quarter of an ounce of powder and four or five pounds employed for a bomb; and were still of opinion that the rope would break.
Having already made experiments, he was still disposed to doubt the truth of this assertion, and therefore tried a four-inch mortar with a ball of the same calibre, and 18 ounces of powder with a rope only three or four lines in diameter, and his success was equally flattering as before. These experiments were repeated by order of government at La Fere, four times with an eight inch mortar, and three times with one of twelve inches, all of which happily succeeded. The same author goes on to observe;
"It ought to be remembered, that a vessel is never cast away, or perishes on the coast, but because it is driven thither against the will of the captain, and by the violence of the waves and the wind, which almost always blows from the sea towards the shore, without which there would be no danger to be apprehended; consequently in these circumstances, the wind comes always from the sea, either directly or obliquely, and blows towards the shore.
"1st, A common paper kite, therefore, launched from the vessel and driven by the wind to the shore, would be sufficient to save a crew of 1500 seamen, if such were the number of a ship of war. This kite would convey to the shore a strong packthread, to the end of which might be affixed a cord, to be drawn on board by means of the string of the kite; and with this cord a rope, or as many as should be necessary, might be conveyed to the ship.
"2d, A small balloon, of six or seven feet in diameter, and raised by rarefied air, would be also an excellent means for the like purpose. Being driven by the wind from the vessel to the shore, it would carry thither a string capable of drawing a cord with which several ropes might be afterwards conveyed to the vessel. Had not the discovery of Montgolfier produced any other benefit, it would be entitled on this account to be considered as of great importance.
"3dly, A sky-rocket, of a large diameter, would be of equal service. It would also carry, from the vessel to the shore, a string capable of drawing a rope after it.
"Lastly, A fourth plan for saving the crew of a shipwrecked vessel, is that of throwing from the vessel into the sea an empty cask with a cord attached to it. The wind and the waves would drive the cask to the shore, and afford the means of establishing that rope of communication already mentioned."
The author just quoted says, that he announced his discovery in a French journal in January 1794. It is, however, to be observed, that the method he proposes of conveying a rope to the shore, by fastening it to a bullet or bomb, to be afterwards fired from a cannon or mortar, was proposed some years ago by a sergeant or officer of artillery at Woolwich, and it is said, similar experiments were made at Portsmouth, and succeeded*.