of the shell be 13 inches, and that of the hollow sphere 9.5. Then the cube of 13 is 2197, and that of 9.5 is 857 357; the difference is 1339.625, its double is 2679.25, which, multiplied by 7, gives 18754.625; and cutting off two places in whole numbers, the result is 187 lb. or 1 cwt. 2 grs. 21 lb., the weight of the shell.

SHELL, a particular part of a sword, which serves as a shield to the hand when it grasps the hilt. The regulation sword, which is directed to be worn in a cross belt, has its shell so constructed, that one side can fall down, by which means the hilt hangs more conveniently.

SHELL, a short jacket without arms, which was worn by light dragoons, and in some instances by the infantry, before the new regulations took place respecting the clothing of the British army. At the commencement of the present war, some militia colonels derived no inconsiderable emolument from this mode of dress

SHELVES, in naval affairs, a general name given to any dangerous shallows, sand-banks, or rocks, lying immediately under the surface of of the water.

SHERARDIA, in botany, so named in honour of William Sherard, L. L. D. consul at Smyrna, a genus of the Tetrandria Monogynia class and order. Natural order of Stellatæ. Rubiaceæ, Jussieu. sential character: corolla one-petalled, funnel-form, superior; seeds two, three toothed. There are three species.

Es

SHERIFF As keeper of the King's peace, the sheriff is the first man in the county, and superior in rank to any noble. man therein, during his office.

He may

apprehend and commit to prison all per sons who break the peace, or attempt to break it, and may bind any one in a recog nisance to keep the King's peace. He may, and is bound, ex officio, to pursue and take all traitors, murderers, felons, and other misdoers, and commit them to gaol for safe custody. He is also to defend his country against any of the King's enemies, when they come into the land; and for this purpose, as well as for keeping the peace and pursuing felons, he may command all the people of his county to attend him, which is called the posse comitatus, or power of the county; which summons every person above fif. teen years of age, and under the degree of a peer, is bound to attend, upon warning, on pain of fine and imprisonment. Yet he cannot exercise the office of a justice of the peace; for then this inconve

nience would arise, that he should command himself to execute his own precepts.

The sheriff has a jurisdiction both in criminal and civil cases, and therefore he has two courts: his town court for criminal causes, which is the King's court; the other in his county court, for civil causes, and this is the court of the sheriff himself. When the new sheriff is appointed and sworn, he ought, at or before the next county court, to deliver a writ of discharge to the old sheriff, who is to set over all the prisoners in the gaol, severally by their names, (together with all the writs,) precisely, by view and indenture between the two sheriffs; wherein must be comprehended all the actions which the old sheriff has against every prisoner, though the executions are of record; and till the delivery of the prisoners to the new sheriff, they remain in the custody of the old sheriff, notwithstanding the letters patent of appointment, the writ of discharge, and the writ of delivery. Neither is the new sheriff obliged to receive the prisoners, but at the gaol; but the office of the old sheriff ceases when the writ of discharge is brought to him.

By 3 George 1. c. 15, it shall not be lawful for any person to buy, sell, let, or take to farm, the office of under sheriff, or deputy sheriff, or seal keeper, county clerk, shire clerk, gaoler, bailiff, or any other office pertaining to the office of high sheriff, or to contract for any of the said offices, on forfeiture of 500l.; one moiety to his Majesty, the other to such as shall sue in any court of Westminster, within two years after the offence.

Provided that nothing in this act shall prevent any high sheriff from constituting an under sheriff, or deputy sheriff, as by law he may; nor to hinder the under sheriff, in any case of the high sheriff's death, when he acts as high sheriff, from constituting a deputy; nor to hinder such sheriff, or under sheriff, from receiving the lawful perquisites of his office, or for taking security for the due answering the same; nor to hinder such sheriff or under sheriff, deputy sheriff, seal keeper, &c. from accounting to the high sheriff for all such lawful fees as shall be by them taken, nor for giving security so to do; or to hinder the high sheriff from allowing a salary to his under sheriff, &c. or other officers And if any sheriff shall die before the expiration of his year, or before he be superseded, the under sheriff shall nevertheless continue in his office, and execute the same in the name of the de

ceased, till another sheriff be appointed and sworn and the under sheriff shall be answerable for the execution of the office

during such interval, as the high sheriff would have been; and the security given by the under sheriff and his pledges shall stand a security to the King, and all persons whatsoever, for the performing his office during such interval.

There is no particular qualification in lands required for the office of sheriff, but a sheriff cannot be elected to serve in parliament for the county of which he is sheriff. The under sheriff performs nearly all the duties of the sheriff. He is not to hold his office above one year, under the penalty of 2001. And no under she riff or bailiff shall practise as an attor ney; but this is so openly evaded, that no person is appointed under sheriff except an attorney.

SHIELD, an ancient weapon of defence, in the form of a light buckler, borne on the arm, to turn off lances, darts, &c.

SHIELD, in heraldry, the escutcheon or field on which the bearings of coats of arms are placed.

SHILLING, an English silver coin equal to 12 pence, or the 20th part of a pound sterling. This was a Saxon coin, being the 48th part of their pound weight. Its value at first was 5 pence; but it was reduced to 4 pence about a century before the conquest. After the conquest, the French solidus, of 12 pence, which was in use among the Normans, was called by the English name of shilling; and the Saxon shilling of four pence took a Norman name, and was called the groat or great coin, because it was the largest English coin then known in England. From this time the shilling underwent many alterations. In the time of Edward I. the pound troy was the same as the pound sterling of silver, consisting of 20 shillings; so that the shilling weighed the 20th part of a pound, or more than half an ounce troy. But some are of opinion there were no coins of this denomination, till Henry VII. in the year 1504, first coined silver piece of 12 pence value, which we call shillings. Since the reign of Elizabeth, a shilling weighs the 62d part of a pound troy, or 3 dwts. 203 grs. the pound weight of silver making 62 shillings. And hence the ounce of silver is worth 5s. 2d. or 51 shillings.

SHINGLES, in building, are generally made of cedar, cypress, and oak stuff, from one to three feet long, split into lengths from three to seven inches wide, and shaved into the shape of a wedge,

three quarters of an inch thick at the butt. Shingles are used as a covering to the roofs of houses, steeples, &c. ; laid and nailed on oak lath, beginning at the eaves, ascending the rafters, and lapping one another in successive courses, from five to seven inches deep.

SHIP building. The man of science and the practical shipwright have long lamented, that in the theory of the art of ship-building there are so few fixed and positive principles established by demonstration, or confirmed by practice; thus the artist, being left to the exercise of his own opinion, in general resists theoretical propositions, however speciously founded, so hard has it ever been found to overcome habitual prejudices.

The great neglect of the theory of ship-building is much to be deplored in a country like this, where the practical part is so well understood and executed. Mathematics, engineering, and civil or house architect, are sciences nourished and taught in our universities and other schools, and however superior scholars may arrive in those arts, and celebrated draughts, or talk to them of the science for their abilities, show them shipping of ship-building, and they appear as much at a loss as though they had never heard of such an art; nevertheless, it may be but justice to add, that some men of different professions have felt themselves interested in its progress to perfection, of men conversant in the practical parts and lately we have seen the endeavours of ship-building, publishing their ideas, and this in hopes that gentlemen of more scientific abilities may be induced to add to their labours, and make the theory of ship-building much more familiar in this country, as few, very few, professional shipwrights have hitherto had it in their power to employ their talents to improve this science by theory.

Ships are bodies, which, when to be put force, and a contrary element, as air or in motion, have water for their resisting wind for their impelling force: therefore the theorist and practical ship-builder should ever keep particularly in view to floating bodies, and endeavour to gain a improve himself in the knowledge of complete knowledge of the resistance of fluids; add to this aerostatics and mathematics in general. Thus taught, the man of practice would, though cautiously, add the speculation of the theorist, as there is a great deal to be risked, and much to be suffered; but could the ideas of the theorist and the man of practice be assi

milated and well weighed together, much benefit to the art of ship-building might be acquired, and their most useful ideas be reduced to the test of experiment.

When experience favours theory, then we arrive at the desired point; but the difficulty and expense of accurately mak ing a sufficient number of experiments is a great hindrance to its assumption, and has greatly hindered that desired knowledge in this branch of science. Notwithstanding these obstacles, many opportunities offer of introducing well digested theory, though cautiously and by degrees, into the many various ships and vessels building in this kingdom; and thus we would hope, by the united efforts of the theorist, ship-builder, and mariner, who should carefully notice and report every observation in his power of the vessel acting in her various situations, that the different results being accurately stated, desirable data may be reasonably established.

It is well known that bodies of any magnitude could not be built or put together without designs or drawings on convenient scales, particularly that complex machine a ship; therefore an accurate delineation of the whole vessel, with respect to its various lengths, heights, breadths, and depths, is carefully represented by a drawing, called the sheer draught, the construction of which, with its several lines, &c. we shall endeavour as familiarly as possible to describe to our readers.

The principal dimensions as they are generally termed, must be first decided upon, and they are the following, viz.

Burthen in tons, resulting from the extreme breadth and length of the keel for tonnage, being multiplied into each other by a rule given hereafter.

Now these are called the principal dimensions, which we will endeavour to describe, with their concomitant circumstances, in their above order; and, first, the length on the gun-deck; this in ships of war must ever contain sufficient distance between the perpendiculars for all the ports, and room between each port for working the guns, and what may be required at the extremities, such as the manger at the fore-part and abaft, room for the after-port to come clear of the wing transom knee, &c. It will also appear evident, that the distance between each port in the clear must contain space sufficient for two frame timbers and the filling timbers between, and the room or openings between the timbers. Thus we find by established practice the distance between, and size of, the ports, in the following class of ships in the navy, are as follow:

The length of the keel for tonnage, as was before observed, is produced from the former dimension, and a length given by a rule, although long established, is very defective, and the tonnage or burthen of the vessel, as it is sometimes called, is said to be produced therefrom. It may be therefore readily seen, that those two dimensions only cannot possibly give any true burthen, for those two dimensions may be alike in two vessels, of the greatest difference in their construction ima. ginable, for one vessel may be so constructed from the same dimensions, as to be very sharp under her load draught

of water, with a very quick rising, to possess the requisite qualities for fast sailing, as the sloop of war; while another vessel keeping the dimensions the same, may be constructed as full under water as the most burthensome merchant ships. Sometimes the production of this rule is called builder's tonnage, as a contradistinction to the true tonnage, and by this result builders are paid a certain price per ton for building any vessel.

THE RULE FOR CASTING THE TONNAGE,

In the royal navy, is to take the length