CIV 



decomposition, though not very readily. 

 The more powerful acids decompose it, 

 though with some difficulty. Concen- 

 trat ",d sulphuric acid converts it into ace- 

 tic acid. Scheele remarked, that nitric 

 acid did not convert it, as it did some of 

 the other vegetable acids, into oxalic 

 acid ; but Fourcroy and Vauquelin have 

 found that, when acted on by a large 

 quantity of nitric acid for a long time, it 

 affords a small portion of oxalic, with a 

 larger portion of acetic acid. 



Citric acid combines with the alkalies 

 and earths, forming salts denominated 

 citrates. The citrate of potass is very 

 soluble, and does not crystallize but with 

 difficulty, and is deliquescent : its taste is 

 purely saline, and rather mild. It con- 

 tains "55.55 of acid, and 44.55 of alkali. 

 Citrate of soda is likewise very soluble, 

 requiring little more than its weight of 

 water for its solution : it crystallizes in 

 six-sided prisms, and the crystals are 

 slightly efflorescent. Their taste is faintly 

 saline ; the proportions of the solid salt 

 are 607 of acid, and 39.3 of soda. Ci- 

 trate of ammonia is equally or even more 

 soluble than the others, and does not cry s- 

 tallize but when its solution is much con- 

 centrated : the form of its crystals is an 

 elongated prism. It consists of 62 of acid, 

 and 38 of ammonia. The earthy citrates 

 are in general less soluble. When the so- 

 lution of barytes is poured into the acid, a 

 precipitate, soluble in the liquid by agita- 

 tion, is formed : when the whole is satu- 

 rated, the salt is deposited at first in the 

 form of a powder, which is covered after- 

 wards with a kind of crystalline efflores- 

 cence, and which a large quantity of water 

 dissolves. It consists of 50 of acid, and 

 50 of base. When the citric acid is 

 saturated by lime, small crystals are 

 deposited, which are very sparingly so- 

 luble : 100 parts contain 62.66 of acid, 

 and 37.34 of lime. When saturated by 

 magnesia, the concentrated solution does 

 not easily crystallize regularly, but rather 

 assumes the state of a white, opaque, and 

 somewhat spongy salt. The proportions 

 of the salt, are 66.66 of acid, and 33.34 

 of base. 



Vauquelin has likewise examined the 

 action of citric acid on the metals. It 

 does not dissolve silver ; but it com- 

 bines with its oxide, and forms a salt, 

 insoluble, of a harsh and strong metallic 

 taste, and which, like the other salts 

 of silver, is blackened by light : it is 

 also decomposed by heat, sometimes leav- 

 ing metallic silver intermixed with char- 

 VOL. III. 



coal. It consists of 36 of acid, and 64 of 

 oxide . 



Citric acid, in its crystallized state, can. 

 be preserved for any length of time with* 

 out decomposition ; and a grateful lemon- 

 ade may be prepared from it, by dissolving 

 30 or 40 grains in a pint of water, with the 

 addition of a little sugar ; and to communi- 

 cate flavour,a little lemon peel,or powder, 

 formed by rubbing sugar on the fresh le- 

 mon. The lemon juice may be regarded 

 as a specific in scurvy, and there is every 

 probability that the crystallized citric 

 acid may be equally effectual. 



CITRUS, in botany, a genus of thePo- 

 lyadelphia Icosandria class and order. 

 Natural order of Bicornes. Aurantia, Jus- 

 si eu. Essential character : calyx five- 

 clefr ; petals five, oblong; anthers twenty ; 

 filaments united into various bodies ; berry 

 nine-celled. There are five species; of 

 which we shall notice the C. aurantium, 

 orange-tree ; of this there are sixty varie- 

 ties. 1. Seville orange, which is a hand- 

 some tree, and the hardiest of any, as it 

 shoots freely in this country, and yields 

 fruit of excellent quality for domestic 

 uses. 2. The China orange, which does 

 not come to perfection here, but in warm 

 countries it grows in the open ground. 

 5. The forbidden-fruit tree, which resem- 

 bles the common orange, but the fruit 

 when ripe is larger and longer than the 

 biggest orange : besides these, there are 

 the horned orange ; the hermaphrodite 

 orange ; and the dwarf. C. Medica, the 

 citron tree ; of this species the lemon 

 tree is accounted a variety ; of which 

 there are many sorts. The flowers of 

 all the species appear in May and June, 

 and the fruit continues setting in June 

 and July, and ripens the year following. 



CIVET, a kind of perfume, bearing the 

 name of the animal whence it is taken. 

 The animal commonly known by the 

 name of the civet, or civet-cat, is the vi- 

 verra civetta of Linnaeus. 



The civet is an animal of a wild dispo- 

 sition, and lives in the usual manner of 

 others of this genus, preying on birds, 

 the smaller quadrupeds, &c. It is a na* 

 tive of several parts of Africa and India : 

 but not of America, as some have erro- 

 neously asserted ; though it has been 

 transported from the Phillippine Islands, 

 and the coast of Guinea. This animal, as 

 well as the zibet, though ^originally na- 

 tives of the warm climates of Africa and 

 Asia, are capable of subsisting in tempe- 

 rate and even in cold countries, provided 

 they are defended from the injuries *f 



C c 



