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refembling that of camphor, only not quite fopowerful. In this Hate it floats on the furfaceof water, and communicates to it a camphoricflavour; is very inflammable, foluble in al-cohol, and precipitable from it by the additionof water. Nitric acid a&s upon it in the famemanner but more flowly than upon Ealt Indiancamphor; but it appears to be wholly infolublein acetic acid.

The prefence of camphor has been fhowr infucli a variety of fubftances, in all of Widthwhen brought to the higheft degree of purifi-cation it appears to be abfolutely the fame, thatit may be confidered as one of the fecondaryvegetable principles ; and an accurate inveftiga-tion of its properties and compofition becomesan enquiry of confiderable intereft.

Camphor on account of its volatility requiresto be kept in well clofed vefiels, it is not how-ever by any means fo cafdy evaporable as isgenerally fuppofed. According to Kunfemuller, dpulverized camphor fpread thin, and expofedto the air at a temperature not exceeding 5 2°Fah. does not lofe more than half its weight in16 weeks; the ratio of volatilization howeverrapidly increafes with an increafe of tempera-ture. The moifture of the air alfo has a con-fiderable effect, the lofs of camphor beingmuch greater in a humid atmofphere than in adry one. The degree at which camphor meltsis fixed by Venturi at 302° Fah. and, by dividinga mafs that has been cooled flowly in the direc-tion of its laminae, it appears to cryflallize inoctahedrons.

Water has little or no adtion on camphor ; ata boiling heat however it takes up enough toacquire both the odour and flavour of this fub-ftance. By the affiftance of gum-mucilage orfugar, it forms with water a wliitifli emulfion.

Alcohol at the ufual temperature, will takeup between a feventh and an eighth of its weightof camphor, and when boiling it will diffolve halfits weight, the greater part of which is againdepofited by cooling. If equal parts of cam-phorized alcohol and fulphuric acid are diftilledtogether, the produce is camphorized ether, anda tenacious black refinous mafs remains in theretort.' Camphor is alfo copioufly foluble infulphuric, and probably in all the other ethers.When camphorized alcohol or ether is mixedwith water, nearly the whole of the camphorfeparates in the form of curdy flakes, which be-in g dried gradually, exhibit the camphor unal-tered in any of its properties. Oils, both the

Mourn Phyf.xxxv.p. i 9 x. « Monnet in Journ. de Phyjs Dorfurtj abhandlungen ubcr den Camphor.

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exprefled, the effential and the empyreuinatiecombine with camphor, as alfo do the refins andbalfams. The hardeft and dryeft refins are con-verted by it into a foft tenacious mafs remark-ably foluble in alcohol; it will even render copalconfiderably foluble in this fluid. The alkalieswhether in their cauftic or carbonated Hate haveno action whatever on camphor: nor will theyunite even when digefted with oil or foap. f .

Sulphur and camphor will combine togetherby means of a very gentle fufion : the refultingmafs is brittle when cold, but foft and tenaciouswhen warm. The alkaline fulphurets will alfounite by fufion with camphor, and retain itwhen diflolved in water : the addition of an acidthrows down the fulphur and camphor in in-timate combination with each other. £

When fet fire to in atmofpheric air, and ftillmore in oxygen gas, camphor burns with a co-pious white flame and black fmoke, and is en-tirely confumed. A large quantity of carbonicacid is produced together with carburetted hy-drogen. The ultimate conftituent parts of cam-phor appear to be carbon, hydrogen, and oxygen,but in what proportions is not yet afeertained.

Camphor when diftilled per fe rifes unaltered,hut if mixed with bole in the proportion of fourparts of the latter to one of the former, and fub-jefted to dry diftillation, it is converted to Xbutyraceous confiftence; and by a fecond dif-tillation with frelh bole is entirely refolved intoa fluid colourlefs oil, and a fmall quantity of awatery acidulous liquor, fmelling ftrongly ofcamphor : the bole is at the fame time reducedto a black fparkling powder, being almoft en-tirely deoxygenated. Clay, according to LaGrange, produces the fame effect. This oil ofcamphor, according to Kofegarten, 1 is nearly co-lourlefs, has a peculiar odour like that of thymeor rofemary, and bears a clofe analogy to theeffential oils. It is foluble in alcohol and fepa-rable, unaltered, from its folution by agitationwith water. It forms favonules with the alka-lies. It is eafily volatilizable by heat, but depofitson the edges of the veffel a white uninflammablecruft which is foluble in water. Nitric acidproduces no other effect on it than tinging it ofa reckliih colour; and even a mixture of con-centrated fulphuric acid and fuming nitric acid,only deepens its colour ftill more, and brings itto a fomewhat thicker confiftence.

Carbonic acid promotes in a remarkable degreethe folubility of camphor in water. k For thispurpofe let finely pulverized or precipitated

'. V. p. 456. f Bindheim in Crell’s neuft. Entd. xi. p, ut.

* Be Camphora. “ Own Experiment.

2 Jf