Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/787

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G A U

the fruftum, then compute the content of a cylinder of this diameter, and ot' the fame height with the veflel, and from this fubftratS -j of the content of a cylinder of the fame height, on a Safe, the diameter of which is equal to that height; the remainder will give the content of the veflel. That is, if D reprefent the diameter of the middle fe&ion, and H the height of the fruftum, you are to fubftitute DD — i HH for the fquare of the diameter of the cylindric veflel in the firft fix rules.

10° When the veflel is a fruftum of a fpheroid, if the bafes are equal, the content is readily found by the rule given in the cyclopaedia from Oughtred. In other cafes, let the axis of the folid be to conjugate axis, as n to I ; let D be the Dia- meter of the middle fe£tion of the fruftum, H the height or length of the fruftum, and fubftitute in the firft fix rules DD — HH for the fquare of the diameter of the veflel.

G A Z

rather than a religious feci, the fame with the Galilaans, Hoffm> Lex. in voc. See Galiljeans, Cycl.

GAULUS, in antiquity, a fhip of a roundifh form, moftly ufed by the people of Phoenicia. Gaulus, alfo fignified akind of cup. Pitifc, Lex. Ant. in voc,

GAVOTTA, or Gavotte, in the Italian mufic, is a kind of dance, the air whereof has two drains, brifk and lively, and in common time ; each of its ftrains are played twice over, the firft has ufually four or eight bars, and the fecond contains fight, twelve, or more. The time begins with a minim, or two crochets, or notes of equal value, and the hand rifing ; and ends with the fall of the, hand upon the do- minant, or mediant of the mode, never upon the final, un- lefs it be a rondeau. And the laft begins with the rife of the hand, and ends with the fall upon the final of the mode. Broff. Did. Muf. in voc.

Tempo di Gavotta, in the Italian mufic, is when only the

wotta, in the Italian i

11°. When the veflel is an hyperbolic conoid, let the axes of I time or movement of a gavotte is imitated, without any re-

the folid be to the conjugate axis, as n to r, D the diameter gard had to the meafure or number of bars, or ftrains. We

of the feclion at the middle of the fruftum, H the height! often find parts of fonnatas, which have this phrafe to regu-

, -, . -p.-!-* , HH , P , A . . ., . c c ... .,1 late their motions. Broff. Muf. Diet, in voc.

or length, compute uu-\- — and lubftitute this (urn tor the v wttpdft a ^ ^ c a • r

u J & ' v ! 3«n GAYIICPUA, in zoology, the name of an American fpecies

fquare of the diameter of the cylindric veflel in the firft fix rules. ; of ferpent, found as it is (aid only in the kingdom of Razim. It

I2 Q . In general, .it is ufual to meafure any round veflel, by J grows to a vaft fize, and ftinks fo intolerably, that no crea-

diftinguifhing it into feveral fruftums, and taking the diame- I ture can bear to be near it. Ray's Syn. anim. p. 329.

ter of the fection at the middle of each fruftum ; thence to GAZA giovane, in zoology, the name of a fmall fpecies of

compute the content of each, as if it was a cylinder of the mean diameter ; and to give their fum as the content of the veflel. From the total content computed in this manner they fubftraft fucceflively the numbers which exprefs the cir- cular areas that cqrrefpond to thofe mean diainetcrs, each as often as there are inches in the altitude of the fruftum to which it belongs, beginning with the uppermoft ; and inj this manner calculate a table for the veflel, by which it readily appears how much liquor is at any time contained j in it, by taking either the dry, or the wet inches ; having] regard to the inclination, or drip of the veflel, if it has j any.

This method of computing the content of a fruftum from I the diameter of the fe&ion at the middle of its height, is exaft in that cafe only when it is a portion of a parabolic ' conoid ; but in fuch veflels as are in common ufe the error is not confiderable. When the veflel is a portion of a cone or hyperbolic conoid, the consent by this method is found lefs than the truth ; but when it is a portion of fphere or fphe- roid, the content computed in this manner exceeds the truth. The difference or error is always the fame in the different parts of the fame, or- of fimilar veflels, when the altitude of the fruftum is given. And when the altitudes are different, the error is in the triplicate ratio of the altitude. If exact- nefs be required, the error in meafuring the fruftum of ;a co- nical veflel, in this manner, is \ of the content of a cone, fimilar to the veflel, of an altitude equal to the height of the fruftum. In a fphere it is \ of a cylinder of a diameter, and height equal to the fruftum. In the fpheroid and hyperbolic j conoid, it is the fame as in a cone, generated by the right! angled triangle contained by the two femiaxes of the figure ] revolving about that fide which. is the femiaxis of the fru- ftum. Thefe are demonftrated in a trcatife of fluxions by Mr. Mac Laurin d , where thofe theorems ar-e extended to fruftums that are bounded by planes oblique to the axis in all the folids, that are generated by any conic fedtion revolving about either axis. [Vid. pag. 25. and 715.] In the ufual method of computing a table .for a veflel, by fubdudting from the whole content the number that exprefies the uppermoft area, as often as there are inches in the up- permoft fruftum, and afterwards the numbers for the other areas fucceflively, it is obvious that the contents afligned by the table, when a few of the uppermoft inches are dry, are ftated a little too high, if the veflel ftands on its lefler bafe, but too low when it ftands on its greater bafe ; becaufe, when

heron, of a fine white colour, called by other authors ardea alba minor, or the fmall white heron. It is fo fmall as not to weigh a pound. Its whole body is of a pure and perfect fnow white, and it has a (hart creft on the hinder part of its head, and a naked fpace which is greenifh about its eyes. Its feet alfo are green, but are fometimes covered with blackifh fcales. The feathers of the creft are very foft and white, and are much valued. It is eaten in Venice and Italy, and is com- mon enough in the markets there. The creft feathers however are ufually pulled oft' before it is offered to fate. Rays Orni- thol. p. 205.

GAZAR, a name ufed by fome authors for the bay tree* John fan.

GAZELLA, the antelope, in zoology, the name of an animal of the goat kind of which there are three known fpecies.

1. The Gazella Africana Strepftcheros Plinti, This is the fpecies we ufually fee under the name of the antelope ; it is called the adduce in Africa, and is the donas lybica of iElian. Its horns are (lender and creel:, they are black, tranfverfely radiated, and twifted into the appearance of fpiral lines ; though thefe are in reality fo many annular circles, they are toward the middle bent a little outwards, and thence they turn in again, fo that they in fome meafure reprefent the antient lyre.

2. The Gazella Indica, or Indian antelope, with very long ftrait horns, which are annulated only in that part near the head. The horns of this creature are fometimes three feet long, and are perfectly fmooth and glofiy, except near the head, and black. The creature is of the fize of our com- mon deer, and is of a greyifh colour ; its tail is a foot long, and Ins longer hairs on it than thofe of the reft of the body. The horns of this fpecies are very common in the mufa?ums of the curious. This creature feems to be the animal which produces the bezoar ftune fo much valued in medicine.

3. The African kind, which has flat horns annulated to the very top, and crooked near the middle ; this has been feen alive fometimes in England. It was much fmaller than our deer, and of a fandy colour ; its belly white, and its fides where the white and fand colour met, of a dufky appearance. Its tail is black and longer than that of the deer, black co- vered with a fmaller number of hairs than thofe of our deer, and white on that part next the body. Its horns grew out of the middle of the forehead near the eyes and are very- long, fharpening at the ends, and all the way marked with tranverfe ftrise of furrows, and a little bent upwards. Its ears are large, and its legs very flende:

ch is dry,

ut itands on its greater oaic ; necauie, wnen ■ are large, aim us ic^j vciy ncnuci .

for example, it is not the area at the middle GAZOPHYLACIUM, in the Jewifli antiquities : this word,

of the uppermoft fniftum, but rather the area at the middle of the uppermoft inch, that ought to be fubducted from the to- tal content, in order to find the content in this cafe.

GAVIAON, in zoology, the name by which the Portugueze called -the caracara, a fpecies of Brazilian hawk, ofthebignefs of our kite. Ray's Ornitholog. p. 42. See Caracara.

GAVILAN, in natural hiftory, a name given by the Spaniards to a fpecies of hawk, common in the Philippine iflands ; it is fomewhat larger than our fparrow hawk, and is of a yellow- ifh colour on The back and wings, and whitifh under the belly ; it is the moft common of all the birds of prey in that part of the world, and is very voracious, and mifchievous.

GAVIOTA, in zoology, the name given by the Portugueze to a water fowl of the gull kind, common in Brafil, and call- : cd by the natives Guaca guacu. It is of the fize of a common hen, its beak is long, ftrait, and yellow, its head is black on the top, as is alfo the farther half of the wings and tail : j the throat, breaft and belly are white, it lays in the fand, I and its eggs are of the fize of thofe of the hen ? and arc ac- counted very good, but the flcfli is not valued.

GAULONITjE, among the Jews, the name of a fail ion I

according to the Greek etymology, Signifies the treafury- chamber. There were feveral places in the temple of Jeru- falem, where the rich prefents confecrated to God by kings, princes, or private perfons were kept. But the fignification of this word Gazophylacium, has been farther inlarged, fo as to comprehend the rooms where the provifions of the temple were laid up, both for facrifices, and for the fupport and fuftenance of the pfiefts, and in general this word is ufed for all the apartments of the temple. In the gofpel, by Gazo- phylacium is meant the cheft into which people caft their offerings at the entrance of the temple. It has been alfo ufed by naturalifts for a collection of figures of curious fubjefts. Mark. c. xii. jt 41, 43. Luk. c. xxi. jr 2. Calm. Di&. Bibl.

GAZOPHYLAX, r«^W, in antiquity, an officer who had the care and management of the treafure belonging to the kings of Perfia. Hoffm. Lex. in voc.

GAZZA, in zoology, the name of a fpecies of heron com- mon in Italy, and called by many authors ardea alba major, the greater white heron. Its whole body is of a fnow white, its beek yellow, ' and the membranes about its eyes green, 'though called large in comparifon of tpe" leflcr white one ;

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