Page images
PDF
EPUB

tion. The sides, from the floor-heads to would be in danger of being filled. The the top of the gunwale, flannch off on each internal shallowness of the boat from the side, in proportion to above half the breadth gunwale down to the platform, the conof the floor. The breadth is continued far for- vexity of the form, and the bulk of cork wards towards the ends, leaving a sufficient within, leave a very diminished space for length of straight side at the top. The the water to occupy; so that the life boat, sheer is regular along the straight side, and when filled with water, contains a consimore elevated towards the ends. The gun- derable less quantity than the common boat, wale fixed to the outside is three inches and is in no danger either of sinking or thick. The sides, from the under part of overturning. the gunwale, along the whole length of the may be presumed by some, that in regular sheer, extending twenty-one feet cases of high wind, agitated sea, and six inches, are cased with layers of cork, to 'broken waves, a boat of such a bulk could the depth of sixteen inches downwards; not prevail against them by the force of and the thickness of this casing of cork be oars; but the life-boat, from her peculiar ing four inches, it projects at the top a lit- form, may be rowed a head, when the at. tle without the gunwale. The cork on the tempt in other boats would fail. Boats of outside is secured with thin plates, or slips the common form, adapted for speed, are, of copper, and the boat is fastened with of course, put in motion with a small powcopper nails. The thwarts, or seats, are er; but, for want of buoyancy and bearing, five in number, double banked ; conse are over-run by the waves, and sunk, when quently the boat may be rowed with ten impelled against them; and boats conoars. The boat is steered with an oar at structed for burthen meet with too much each end; and the steering oar is one third resistance from the wind and sea, when longer than the rowing oar. The platform opposed to them, and cannot, in such cases, placed at the bottom, within the boat, is be rowed from the shore to a ship in dishorizontal, the length of the midships, and

tress. elevated at the ends, for the convenience of BOATSWAIN, a ship-officer, to whom the steersman, to give him a greater power is committed the charge of all the tacklings, with the oar. The internal part of the boat sails, and rigging, ropes, cables, anchors, next the sides is cased with cork; the whole flags, pendants, &c. He is also to take care quantity of which affixed to the life-boat of the long-boat and its furniture, and to is nearly seven hundred weight. The cork, steer her either by himself or his mate. indisputably, contributes much to the buoy He calls out the several gangs and comancy of the boat, is a good defence in going panies aboard, to the due execution of their along-side a vessel, and is of principal use watches, works, spells, &c. He is likewise in keeping the boat in an erect position in provost-marshal, who sees and punishes all the sea ; or, rather, for giving her a very offenders sentenced by the captain, or a lively and quick disposition to recover from court-martial of the fleet. He ought freany sudden cant or lurch, which she may quently to examine the condition of the receive from the stroke of a heavy wave. masts, sails, and rigging, and remove whatBut, exclusively of the cork, the admirable ever may be unfit for service, or supply construction of this boat gives it a decided what is deficient ; and he is ordered by his pre-eminence. The ends being similar, the instructions to perform his duty “ with as boat can be rowed either way; and this little noise as possible.” peculiarity of form alleviates her in rising BOATSWAIN's mate has the peculiar comover the waves. The curvature of the keel mand of the long boat, for the setting forth and bottom facilitates her movement in turn of anchors, weighing or fetching home an ing, and contributes to the ease of the anchor, warping, towing, or mooring; and steerage, as a single stroke of the steering is to give an account of his store. oar has an immediate effect, the boat moving BOB, a term used for the ball of a short as it were upon a centre. The fine entrance pendulum. below is of use in dividing the waves, when Bob, in ringing of bells, denotes a peal rowing against them; and, combined with consisting of several courses, or sets of the convexity of the bottom, and the ellip- changes. tical form of the stem, admits her to rise BOBARTIA, in botany, a genus of the with wonderful buoyancy in a high sea, and Triandria Digynia class of plants, the calyx to launch forward with rapidity, without of which is imbricated, and contains only a sluipping any water, when a common boat single flower; the corolla is a glume, con

VOL. I.

sisting of two valves, and placed on the ger- inches to a foot in length; filaments ten, nien ; the seed is single, ot' an oval figure, seldom more, longer than the leaflets of the and is contained in the cnp.

calyx, hanging down loose ; anthers longer BOBBIN, a small piece of wood turned than the filaments. It is a native of the in the form of a cylinder, with a little bor West India islands, where the juice of it is der jutting out at each end, bored through used to take off tetters and warts. to receive a smalt iron pivot. It serves to BOCK-LAND, in the Saxons' time, is spin with the spinning wheel, or to wind what we now call freehold lands, beld by thead, worsted, hair, cotton, silk, gold, the better sort of persons by charter or and silver.

deed in writing, by which name it was disBOBBING, among fishermen, a particu- tinguished from folkland, or copyhold land, lar manner of catching eeis different from holden by the common people without sniggling.

writing. BOB-STAYS, in nautical language, ropes BODIANUS, in patural history, a genus used to confine the bowsprit downward to of fishes of the order Thoracici, of which the stem or cut-water. A bob-stay is fixed the generic character is, habit of the genus by thrusting one of its ends through a lole Perca, gill-covers scaly, serrated, and acubored in the fore part of the cut-water for leated; scales generally smooth. They are. this purpose, then splicing both ends toge. divided into two classes, one with divided or ther, so as to make it two-foll, or like the forked tails : the other with even or link of a chain ; a dead-eye is then seized rounded tail. Dr. Shaw, in his excellent into it, and a laniard passing through this zoology, enumerates fifteen species. The and communicating with another dead-eye B. luteus, is about fourteen inches long, upon the bowsprit is drawn extremely and in shape like a trout; the colour is light by the help of mechanical powers. The yellow, each scale being deeply edged or uise of the bob-stay is to draw down the tipped with orange ; the back is purplich bowsprit, and keep it steady, and to coun rose-colour with scales tipped with blue; teract the force of thie stays of the foremast tail nearly in the middle, but running into a which draws it upwards. The bowsprit is lanceolate tip at cach side. It is a vative of also fortified by shrouds from the bows on the South America seas. B. pentacanthus, each side : on this -aud other accounts the or five-spined bodian, is about 13 inches bob-stay is the first part of a ship's rigging long, shape nearly as in the luteus, but rawhich is drawn tight to support the masts. ther more slender, colour beautiful deep

BOCARDO, among logicians, the fifth rose, with a silvery cast on the abdomen; mode of the third figure of syllogisms, in tail deeply forked, the upper lobe stretching which the middle proposition is an universal beyond the lewer ; anterior gill-covers affirmative, and the first and last particular armeil with five strong spines ; it is a nanegatives, thus :

tive of the Brasilian seas, and is very much Bo Some sickly persons are notstudents; esteemed as food. Sce Plate II. Pisces, Car Every sickly person is pale;

fig. 3. 10 Therefore some persons are pale that BODKIN, a small instrument made of are not students.

steel, boue, ivory, &c. used for making BOCCONIA, in botany, so cailed from a hol-. Sicilian monk, a genus of the Dodocandria BODY, in physics, an extended solid Monogynia class and order, Natural order substance, of itself utterly passive and inacof Rhoeadeæ : Papaveracea, Jussieu. Es- tive, indifferent cither to motion or rest; sential character: calyx two-leaved ; corol. but capable of any sort of motion, and of all la none; style bifid; berry dry, one-seeded. figure, and forms. There is only one species, viz. B. frutescens, Body, in gronetry, is a figure extended shabby bocconia, tree celandic, or parrot in all directions, or what is h-ually said to weed, is a shrub rising to the height of ten cousist of leagu, breadth, and thickness. or twelve feet; with a straight trunk as It is usually called a solid. A solid or body large us a man's arm, covered with a white is conceived to be formed by the motion of smooth bark, and branched towards the top. a surface; as surface is by the motion of The trunk is hollow, filled with a piilı, like a line, and a line by the motion of a point. the alder, abounding in a thick yellow juice, Similar bodies are in proportion to each liho argemone, and celandive; branches other, as the cubes of their sides. There brittie, unequal, marked with scars from are five bodies which are denominated rethe tallew leaves; leaves troin six or seven guiar or Platonic bodies; these have all

contained by

their sides, angles, and planes similar and liable to remain in prison, in default of payequal : they are denominated the

ment.

In France, all restraints of the body for Tetraedron -4 equilateral triangles civil debts are null after four months, unless Hexaedron 6 squares

the sum exceeds two hundred livres. or cube Octaedron 8 triangles

A woman, though in other respects she Dodecaedron 12 pentagons

cannot engage her person but to her husIcosaedron (20 triangles.

band, may be taken by the body, when she

carries on a separate trade. In the Plate Miscel. II. fig. 1 to 5, we have Body, among painters; as, to bear a given the figures of each, which, if drawn body; a term signifying that the colours on pasteboard, and cut out by the bounding are of such a nature, as to be capable of belines, and then the other lines being half cut ing ground so fine, and mixing with the oil through, the parts may be turned up and so entirely, as to seem only a very thick oil fastened together by strong paste, so as to

of the same colour. form the respective body marked with the But such colours as are said not to bear a corresponding number. Fig. 1 is the te- body, will readily part with the oil when atraedon: fig. 2 the hexaedron: fig. 3 the laid on the work; so that when the colour octaedron: fig. 4 the dodecaedron, and shall be laid on a piece of work, there will fig. 5 the icosaedron.

be a separation; the colour in some parts,

and the oil in others, except they are, temTo find the superficies or solidity of the regu

pered extraordinarily thick. lur bodics.

BOEBERA, in botany, a genus of the

Syngenesia Superfiua class and order. Re1. Multiply the proper tabular area

ceptacle naked; down simple; calyx dou(taken from the following table) by the ble, the outer many-leaved, inner eightsquare of the linear edge of the solid, for

leaved. One species, found in Carolina and the superficies.

Mexico. 2. Multiply the tabular solidity by the

BOEHMERIA, in botany ; so called in cube of the linear edge, for the solid con honour of George Rudolph Boehmer; a getent.

nus of the Monoecia Tetrandria class and

order. Natural order of Scabridæ. Urti. Table of the surfaces and solidities of the

cæ, Jussieu. Essential character; male, cative regular bodies, the linear edge be- lyx four-parted; corolla none; female, ca. ing 1.

lyx none, but crowded scales between,

each; germ obovate; style single; seed Solidities single, compressed. There are five species;

of which B. caudata, is a shrub growing to Tetraedron 1.73205 0.11785

the height of ten or twelve feet; the leaves 6 Hexaedron 6.00000 1.00000

are very broad. It is frequent in the Octaedron 3.46410 0.47140

cooler mountains of Liguanea, in Jamaica : Dodecaedron 20.64573 7.66312

B. literalis is a native of Hispaniola : B. cyIcosaedron 8.66025 2.18169

lindrica, is an annual plant, with a lucid

herbaceous stalk, dividing into several Bodies, descent of. Heavy bodies, in an branches ; the leaves have three longitudiunresisting medium, tall with an unitormly nal veins, and are placed on pretty long accelerated motion; whence the spaces de foot-stalks; flowers in single catkins, which scended are in the duplicate ratio of the are not divided. Native of North America times and velocity, and increase according and Jamaica. to the uneven numbers 1, 3, 5, &c. The BOERHAVIA, in botany ; so called in times and velocities are in a subduplicate honour of the famous Boerhaave; a genus ratio of the spaces. The velocity of de- of the Monandria Monogynia class and orscending bodies is, in proportion to the der. Natural order of Agregatæ : Nyctatimes from the beginning of their fa'l; and geves, Jussieu. Essential character; calyx the spaces described by a falling body are, none; corola one-petalled, bell-shaped, as the squares of the times from the begin- plaited; seed one, naked, interior. There are ning of their fall. See MECHANICS. seven species ; of these B. erecta ; upright

Body, in law. A man is said to be bound flag weed; has a stem two feet high ; at or held in body and goods; that is, he is each joint a pair of ovato-pointed leaves,

No. of Faces

Names

Surfaces

19 20

whitish underneath ; on foot-stalks an inch to be boiled is exposed. If we diminish the in length ; at these joints, which are far pressure, the liquid boils at a lower tempera asunder, come out also small side branches, ture ; if we increase it, a higher temperagrowing erect; they, as well as the stem, ture is necessary to produce ebullition. From are terminated by loose panacles of flesh- the experiments of Professor Robinson, it coloured flowers, succeeded by oblong glu. appears that, in a vacuum, all liquids boil tinous seeds. This plant is found at La about 145o lower than in the open air, under Vera Cruz, also in the Society Isles.

a pressure of 30 inches of mercury; there. BOILING. When all other circum- fore water would boil in vacuo at 67°, and stances are the same, the evaporation of alcohol at 34°. In a Papin's digester, the liquids increases with their temperature; temperature of water may be raised to and after they are heated to a certain tem- 300°, or even 400°, without ebullition ; but perature, they assume the form of elastic the instant that this great pressure is refluids with great rapidity. If the heat be moved, the boiling commences with proapplied to the bottom of the vessel contain- digious violence. ing the liquids, as is usually the case, after BOLETUS, in botany, so called from the whole liquid has acquired this tempera- its globular form, characterized by Linnæus ture, those particles of it which are next as a horizontal fungus ;, porous, or punched, the bottom become an elastic fuid first: with lobes underneath. In the fourteenth they rise up, as they are formed, through edition of the “ Systema Naturæ,” only the liquid, like air bubbles, and throw the twenty-one species are recited, eleven of whole into violent agitation. The liquid is which are parasitical and stemless, the rest then said to boil. Every particular liquid are stipitated. From B. igniarius is pre. has a fixed point at which this boiling com pared the amadou, commonly used on the mences (other things being the same); and continent for tinder, to receive the spark this is called the boiling point of the liquid. struck from the steel by the fint, and the Thus, water begins to boil when heated to agaric for stopping hæmorrhages in ampu212°. It is remarkable, that after a liquid tations, &c. has begun to boil, it never becomes any BOLT, among builders, an iron fastening hotter, however strong the fire be to which fixed to doors and windows. They are geit is exposed. A strong heat indeed makes nerally distinguished into three kinds, riz. it boil more rapidly, but does not increase plate, round, and spring bolts. its temperature. This was first observed Bolts, in gunnery, are of several sorts, by Dr. Hooke. The following table con as, 1. Transum bolts, that go between the tains the boiling point of a number of li- cheeks of a gun-carriage to strengthen the quids.

transums. 2. Prise bolts, the large knobs of

iron on the cheeks of a carriage which Bodies.

Boiling point.

keep the hand-spike from sliding when it is Ether

98° poized up the breech of a piece. 3. TraAmmonia

...140 verse bolts, the two short bolts that being Alcohol

......176

put one in each end of a mortar carriage, Water......

212 serve to traverse her. 4. Bracket bolts, Muriate of lime..........

230 the bolts that go through the cheeks of a Nitric acid......

......248

mortar, and by the help of quoins keep her Sulphuric acid

.590 fixed at the given elevation. And, 5. Bed Phosphorus

..554 bolts, the four bolts that fasten the brackets Oil of turpentine ...............

...560 of a mortar to the bed. Sulphur

K......570

Bolts, in a ship, are iron pins, of which Linseed oil..........

there are several sorts according to their Mercury......

...660 different make and uses. Such are: drive

bolts, used to drive out others; ray bolts, It will be seen when we come to treat of with jags or barbs on each side to keep the melting point of solids, that it is capa them from flying out of their holes ; clench ble of being varied considerably by altering bolts, which are clenched with rivetting the situation of the body. Thus, water hammets; forelock bolts, which have at the may be cooled down considerably lower end of a forelock of iron driven in to keep than 32° without freezing. The boiling them from starting back; set bolts, used point is still less fixed, depending entirely for forcing the planks and bringing them on the degree of pressure to which the liquid close together; feud or fender bolts, made.

....600

with long and thick heads, and struck into tinue the tube to any length from one foot the uttermost bends of the ship to save her to whatever number is required. sides from bruises; and, ring bolts, used Fig. 7. G, H, two steel pinches or drifts, for bringing to of the planks, and those to be placed on the head of the copper bolt parts whereto are fastened the breeches and within the tube whilst driving. The blow tackles of the guns.

given upon the punch drives forward the There are various inventions for driving bolt. The shortest of them should be used both into ships, and others for drawing them first, and when driven nearly to its head out; we shall describe one by Mr. R. Phil- should be taken out of the tube, and the lips, for driving copper bolts into ships, for longer punch applied in its place. which he received the gold medal from the

BOLTONIA, in botany, so called in Society of Arts, &c. in the Adelphi. The honour of Mr. James Bolton of Halifax, a instrument employed for driving the bolts

genus of the Syngenesia Polygama Superconsists of a hollow tube formed from sepa- fua. Natural order of Compositæ Opporated pieces of cast iron, which are placed sitifoliæ. Essential character: calyx comupon the heads of each other, and firmly

mon subimbricate, with linear scales; corolla held thereto by iron circles or rings over

radiate ; germs compressed, vertical ; down the joints of the tube; the lowest ring is obscurely toothed, two-horned ; receptacle pointed to keep the tube steady upon the honey-combed. There are two species, viz. wood; the bolt, being entered into the end B. asteroides, starwort-flowered boltonia; of the hole bored in the wood of the ship, and B. glastifolia, glaucous-leaved boltonia. and completely covered by the iron tube, Both these are natives of America, and is driven forwards within the cylinder by Aower late in the autumn. an iron or steel punch placed against the head of the bolt, which punch' is struck of cast-iron, having a large vent, by which

BOMB, in artillery, a shell or hollow ball by a mall; and as the bolt goes farther into

it is filled with gunpowder, and which is the wood, part of the tube is unscrewed

fitted with a fuze or hollow plug to give fire and taken off till the bolts are driven home by when thrown out of a mortar, &c.: about into its place up to the head.

the time when the shell arrives at the inThe tubes are about five inches in cir- tended place, the composition in the pipe of cumference, and will admit a bolt of seven

the fuze sets fire to the powder in the shell, eights of an inch in diameter.

which blows it all in pieces, to the great References to Plate, Life Boats, &c.

annoyance of the enemy, by killing the

people or firing the houses, &c. They are Fig. 4. A, the copper bolt, with one end now commonly called shells, simply, in the entered into the wood previous to fixing the English artillery. tube.

These shells or bombs are of various B, a piece of timber or ship's side, into sizes, from that of 17 or 18 inches diameter which the bolt is intended to be driven.

downwards. The very large ones are not Fig. 5. C, C; C, C, the parts of the iron used by the English, that of 13 inches diatube fastened together, ready to be put on meter being the highest size now employed the bolt A.

by them : the weight, dimensions, and other D, D, D, D, iron or brass rings, with

circumstances of them, and the others thumb screws placed over the joints of the downwards, are as in the following table, tube to hold them firm together.

E, E, E, E, the thumb screws, which keep the rings and tube firm in their pro

Weight Powder to per places.

most pieces. F, two points formed on the lower ring, they are to stick into the timber, and to

13 inch 195

94

7 8 enable the tube to be held firm in its

10

3 4 place.

46 2 34 2 0 Fig. 6. Shews the separation of the parts

54 Royal 141 14 0 1.6 of the tube, which is effected by slackening

7 할

07 the thumb screws and rings.

To put them together, you slide the rings over the joints placed as close as possible,

Mr. Muller gives the following proporthen by tightening the thumb screws you tion for all shells. Dividing the diameter will have them firm together, and may con of the mortar into 30 equal parts, then the

Diameter of
the shell.

Powder to fill them, burst them in

of the
shell,

lbs.

lb. oz.

Ib. 02.

4 141

4 Cohorn

0

8

« PreviousContinue »