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on the line is C 6, the mean proportional of the piece, and the depth (at the end) is sought. This done, find the content of a inches : then find a mean proportional be circle, whose diameter is 6 feet; this, when tween the breadth and depth of the piece. found, by the last article, will be equal to This mean proportional is the side of a the content of the ellipsis sought.

square, equal to the end of the piece; weich " Use of Coggeshal's Rule in measuring found, the piece may be measured as square timber.” 1°. To measure timber the usnal timber. For an instance : let the length of way. Take the length in feet, half feet, the piece of timber be 13 feet, the breadth and, if required, quarters; then measure

23 inches, and the depth 13 inches; set 23 half way back again; then girt the tree

on the girt line D, to 23 on C; then against with a small cord or line ; double this line 13 on C is 17.35 on the girt-line D, for the twice very evenly, and measure this fourth mean proportional. Again, setting 12 on part of the girt or perimeter in inches, the girt-line D, to 13 feet, the length of the halves, and quarters. The dimensions thus line C; against 17.35 on the girt-line is 27 taken, the timber is to be measured as if feet, the content. 5o. To measure taper square, and the fourth of the girt taken for timber. The length being measured in feet, the side of the square, thus; set 12 on the note one-third of it; which is found thus girt line D, to the length in feet on the line set 3 on the line A, to the length on the C; then against the side of the square, on

line B; then against i on A is the third the girt-line D, taken in inches, you have, part on B: then, if the solid be round, meaon the line C, the content of the tree in sure the diameter at each end in inches, feet. For an instance : suppose the girt of and subtract the less diameter from the a tree, in the middle, be 60 inches, and the greater ; add half the difference to the less length 30 feet, to find the content, set 12 diameter; the sum is the diameter in the on the girt-line D, and so feet on the line middle of the piece. Then set 13.54 OB C; then against 15, one fourth of 60, on the girt to the length of the line C, and the girt-line D, is 46.8 feet, the content on against the diameter in the middle on the the line c. If the length should be 9 girt-line is a fourth number on the lipe C. inches, and the quarter of the girt 35 Again, set 13.54 on the girt-line to the inches ; here, as the length is beneath a third part of the length on the line C; then foot, measure it on the line of foot-mea. against half the difference on the girt-line is sure, and see what decimal part of a foot it another fourth number on the line C; these makes, which you will find .75. Set 12, two fourth numbers, added together, give therefore, on the girt line, to 75 on the first the content. For an instance: let the radius of the line C, and against 35 on the length be 27 feet (one third whereof is 9) girt-line is 64 feet on C, for the content. the greater diameter 22 inches, and the 2". To measure round timber the true way. lesser 18; the sum of the two will be 40, The former method, though that generally their difference 4, and half the difference in use is not quite just. To measure tim- 2, which, added to the less diameter, gives ber accurately, instead of the point 12 on 20 inches for the diameter in the middle of the girt-line, use another, riz. 10.635; at the piece. Now set 13.54 on the girt-line which there should be placed a centre-pia. to 27 on the line C, and against 20 on D is This 10,635 is the side of a square equal to 58.9 feet. Again, set 13.44 of the girt-line a circle, whose diameter is 12 inches. For to 9 on the line C; and against a on the an instance : suppose the length 15 feet, girt-line (represented by 20) is .196 parts; and of the girt 42 inches, set the point therefore, by adding 58.9 feet to .196 feet, 10.635 to 15, the length; then against 42 the sum is 59.096 feet, the content. on the girt-line is 233 feet for the content If the timber be square, and have the sought; whereas by the common way, there same dimensions ; that is, the length 27 arises only 184 feet. In effect, the counmon feet, the side of the greater end 22 inches, measure is only to the true measure, as 11 and that of the lesser 18 inches ; to find the to 14. 3o. To measure a cube. Suppose content, set 12 on the girt-line to 27, the the sides to be 6 feet each ; set 12 on the length on the line C, and against 20 inches, girt-line D, to 6 on C; then against 72 the side of the mean square on the girt line inches (the inches 6 feet) on the girt-line, is is 75.4 feet. Again, set 12 on the girt-line 216 feet on C, which is the content re- to 9 feet, one third of the length, on the quired. 4o. To measure unequally-squared line C, and against 2 inches, half the diftimber ; that is, where the breadth and ference of the sides of the squares of the depth are not equal. Measure the length ends on the girt-line, is . 25 parts of a foot;

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both together make 75.65 feet, the content RUNIC, a term applied to the language of the solid.

and letters of the ancient Golbs, Danes, The girt or circumference of a tree, or and other northern nations. round piece of timber given; to find the RUNNER, in the sea language, a rope side of the square within, or the number belonging to the garnet, and to the two of inches of a side, when the round timber bolt-tackles. It is reeved in a single block, is squared. Set 10 on A to 9 on B, then joined to the end of a pennant, and has at against the girt on A are the inches for the one end a hook to hitch into any thing, and side of a square on the line B.

at the other end a double block, into RUM, a species of vinous spirit, distilled which is reeved the fall of the tackle, or the from sugar canes.

garnet, by which means it purchases more RUMEN, in comparative anatomy, the than the tackle would without it. paunch, or first stomach of such animals as RUNNET, or Rennet, the acid juice chew the cud, thence called ruminant ani found in the stomachs of calves that have mals. The rumen is by far the largest of all fed on nothing but 'milk, and are killed be. the stomachs, and in it the whole mass of fore the digestion is perfect. crude aliments, both solid and liquid, lies RUPALA, in botany, a genus of the Te. and macerates, to be thence transmitted to trandria Monogynia class and order. Natbe mouth to be again chewed, commiputed, tural order of Contortæ. Protæ, Jussieu. and fitted for further digestion in the other Essential character : calyx vone; petals ventricles.

four, cohering at the base ; stamina inserted The ruminant animals, Mr. Ray observes, into the middle of the petals ; pericarpium are all hairy quadrupeds, viviparous, and one-celled, one-seeded. There are two have four stomachs; they also want the species, viz. R. montana and R. sessilifolia, dentes primores, or broad teeth in the fore. both natives of Cayenne. part of the upper jaw, and are furnished RUPERT'S drops, a sort of glass-drops with that kind of fat called suet, sebum. with long and slender tails, which burst

RUMEX, in botany, dock, a genus of the to pieces on the breaking off those tails in Hexandria Trigynia class and order. Na any part, said to have been invented by tural order of Holoraceæ. Polygoneæ, Jus. Prince Rupert, and therefore called after sieu. Essential character: calyx three. his name. This surprising phenomenon is leaved; petals three, converging; seed supposed to rise from hence, that while the one, three-sided.

There are thirty-six glass is in fusion, or in a melted state, the species.

particles of it are in a state of repulsion ; RUMMAGE, in the sea-language, signi- but being dropped into cold water, it so fies to clear a ship's hold, or to remove condenses the particles in the external goods from one place of it to another. parts of their superficies, that they are

RUMOURS, spreading such as are false, easily reduced within the power of each is criminal and punishable by common law. other's attraction, and by that means they

RUMPHIA, in botany, so named in ho- form a sort of bard case, which keeps con. nour of George Everhard Rumplius, M. D. fined the before-mentioned particles in their a genus of the Triandria Monogynia class repulsive state ; but when this outer-case is and order. Natural order of Terebintaceæ, broken, by breaking off the tail of the drop, Jussieu. Essential character : calyx three. the said confined particles have then a cleft; petals three; drupe three-celled. liberty to exert their force, which they do There is only one species, riz. R. amboinen- by bursting the body of the drop, and resis, a native of the East Indies.

ducing it to a very peculiar form of powder. RUNDLET, or Runlet, a small vessel, RUPPIA, in botany, so named in memocontaining an uncertain quantity of any ry of Henry Bernhard Rappius, a genus of liquor ; from three to twenty gallons. the Tetrandria Tetragynia class and order.

RUNGS, in a ship, the same with the Natural order of Inundatæ. Naiades, Jusfoor or ground timbers, being the timbers sieu. Essential character: calyx none ; which constitute her floor, and are bolted corolla none ; seeds four, pedicelled. There to the keel, whose ends are rung heads. is but one species, riz. R. maritima, sea

Rung heads, in a ship, are made a little muppia, or tassel pond-weed. bending, to direct the sweep or mould of RUSCUS, in botany, butchers broom, a the futtocks and navel timbers ; for here genus of the Dioecia Syngenesia class and the lines, which make the compass and order. Natural order of Sarmentaceæ. bearing of a ship, do begia.

Asparagi, Jussieu. Essential character :

calyx six-leaved ; corolla none ; nectary change before the blow-pipe, without add central, ovate, perforated at the top. There tion, but with borax it forms a yellowish are five species.

green transparent bead; the constituent RUSSELIA, in botany, so named in ho- parts are different according to the place nour of Alexander Russel, M. D. a genus from which the specimens are found; obe of the Didynamia Angiospermia class and from Norway was found to consist of order. Natural order of Personatæ. Scro- Silica ......... ............ 92 phulariæ, Jussieu. Essential character: Oxide of menachine .... 58 calyx five-leaved, setaceous at the end ; Calcareous earth .... 20 corolla tube very long, hairy at the throat;

100 border two-lipped, lower lip trifid ; capsule acuminate, one eelled, two-valved, many- It is found at Passau, in the district of the seeded. There is only one species, viz. R. Inn, and in several Norwegian mines. sarmentosa, found by Jacquin about Havana, RUYSCHIA, in botany, so named in in close woods and coppices.

memory of Frederick Ruysch, professor of RUST of a metal, a word that has now botany at Amsterdam, a genus of the Peogiven way to the modern term OXIDE, tandria Monogynia class and order. Esserwhich see.

tial character : calyx tive-leaved ; coroika RUTA, in botany, rue, a genus of the De- five-petalled, reflexed; style none ; berry candria Monogynia class and order. Natu. many-seeded. There are two species, s. ral order of Multisilique. Rutaceæ, Jus. R. clusiæfolia, and R. surubea. sien. Essential character : calyx five- RYANIA, in botany, so named in honor parted; petals concave ; receptacle sur. of John Ryan, M. D. a genus of the Polyrounded by ten honey dots ; capsule lobed. andria Monogynia class and order. Essentis There are seven species.

character : calyx five-leaved, permanent, RUTILE, in mineralogy, a species of coloured; corolla pone ; stigmas four; the Menachine genus, of a dark blood red berry suberous, one-celled, many-seeded. colour, of various degrees of intensity There is only one species, riz. R. speciosa, passing to a brownish red. It occurs cry. a native of the Isle of Trinidad. stallized, and the crystals are longitudinally RYE. See SECALE. streaked; externally it is shining and glis- RYNCHOPS, the skimmer, in natural tening ; internally its principal fracture is history, a genus of birds of the order splendent. It is slightly translucent, brit- Grallæ. Generic character : the bill greatly tie; it yields a pale yellow or orange yellow compressed ; lower mandible considerably coloured streak. It is easily frangible ; , longer than the upper ; nostrils linear and specific gravity about 4.2. Without addi. pervious ; back toe very small; tail very tion it is infusible before the blow-pipe ; forked. R. nigra, or the black skimmer, the with borax or alkali it affords a byacinth only species, is twenty inches long and three trapsparent glass. It is found to be a pure feet and a half in width. It inhabits America oxide of menachine, with a slight portion of and the East Indies, and is almost incessilica.

santly on the wing, skimming over the surRUTULITE, a mineral found in Nor- face of the water, into which it plunges its way, of a yellowish colour ; it occurs mas. bill with extreme frequency, to seize small sive, disseminated, and crystallized. The fishes, which constitate its chief food. The crystals are small, singly imbedded, and structure of its bill enables it to open seldom aggregated. It is translucent on oysters-and other shell fish with extreme the edges, or opaqne, yields a grey streak ; ease, and in stormy weather it is seen on the it is hard, brittle, and easily frangible. Spe" shores opening and devouring them. See cific gravity 3.5. It experiences little Aves, Plate XIII,

END OF VOL. 1.

C. WHITTINGHAM, Printer,

108, Goswell Street.

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Fig... Motacilla mademspatensis : Pied - Nantail-Fig.2. Muscicapa atricappilla : Pied Fly catcher - Fig.3. Motacilla regulus:Golden ere.sted Wnn -F19.4. M.luscina: Nightingale. Fig.5. Numidia pintado : trinca hen_fin.6. Oriolus hamorrhour: Rari rumped Oriole. Mio.7. Parus major: Grater Titmouse. Fiq8 Parulaus: Blue Titmouse.

Lonelin n blintatlo 1

...n Hunn Rewa bermain 1808.

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