ALB 



ALB 



the Cyclopaedia, deferve to be more fully detailed here, as 

 much additional light has been tlirown on the fubjeft within 

 the laft few years, from the labours of Berzelius and others. 

 Acids, as is well known, precipitate albumen immediately ; 

 at leaft this is the cafe with all the mineral acids when con- 

 centrated. Dilute phofphoric, fluoric, and acetic acids, 

 however, do not precipitate albumen. Coagulated albumen, 

 according to Berzelius, is charred by concentrated fulphuric 

 acid ; but when diluted with fix or feven times its weight 

 of water, and digefted with it, the acid affumes a reddifh 

 colour, but difTolves fcarcely any thing. The portion not 

 diffolved he confiders as a compound of albumen with cxcefs 

 of acid. On depriving it of this excefs of acid, by wafliing 

 k with pure water, a neutral combination is obtained, which 

 is foluble in water. This folution reddens litmus paper, and 

 yields a precipitate with acids as well as alkalies, the former 

 being combinations of the albumen with the acid employed, 

 and wliicli may be again rendered foluble by wafhing in 

 water, the latter being again foluble with a flight excefs of 

 alkaU. Hence he confiders fulphuric acid to be capable of 

 combining with albumen in two proportions ; one in which the 

 acid is neutralized, and which is foluble in water ; the other, 

 in which the acid is in excefs, and which is infoluble in water. 

 In dilute muriatic acid fcarcely any of the albumen is dif- 

 folved, even by boiling, neither does the acid liquor afford 

 any precipitate with ammonia, or pruffiate of potafh. Eva- 

 porated to drynefs, a brownidi refidue is obtained, from 

 which potafh difengages a little ammonia. Concentrated 

 muriatic acid decompofes albumen by boihng, and produces 

 a red or violet-coloured folution. The albumen that has 

 been digefted in weak muriatic acid, by wafhing repeatedly 

 with water, is converted into a gelatinous mafs, wliich is 

 perfectly foluble in tepid water : this is to be confidered 

 as a neutral combination of albumen with the acid, while the 

 former one contains an excefs. The folution has the fame 

 properties nearly as that of fulphuric acid above-mentioned. 

 Nitric acid of fp. gr. 1.25, digefted with albumen, renders 

 it yellow, and diminifhes its cohefion. The fluid becomes 

 yellow, and a fmaU quantity of fatty matter is formed. 

 During this procefs, azotic gas is given out in abundance. 

 After twenty-four hours, the albumen is converted into a 

 pulverulent mafs of a pale citron colour, which is depofited 

 at the bottom. This matter being feparated and well 

 wafhed acquires a deep orange colour, which Berzehus con- 

 fiders as the aciJe jaune of Fourcroy and Vauquehn, who 

 obtained it by digefting mufcular flefh with nitric acid. 

 This is foluble in alkaline leys, and imparts to them an 

 orange colour ; and it is alfo foluble in acetate of potafh and 

 foda. Thus, according to Berzelius, albumen is capable 

 of exifting with the nitric acid, as well as with the other 

 acids, in two diftind ftates of combination, the one having^ 

 an excefs of acid, and of a pale yellow colour, and the other 

 neutral, and of an orange hue. Berzelius feems to confider 

 the different nature of tTie compounds formed with nitric 

 acid to depend upon the formation of the mahc acid, by the 

 aftion of the nitric acid upon the albumen, which at the 

 fame time combines with it. Hence, in his opinion, they are 

 triple compounds of albumen, nitric and malic acids. Mr. 

 Hatchett found, that if albumen, after being fteeped in 

 diluted nitric acid, be wafhed, and then boiled in water, it is 

 diffolved, and forms a pale yellow liquid, which gelatinizes 

 when properly concentrated, and has all the properties of 

 gelatine. Perhaps this boihng deprives it of the malic acid 

 above-mentioned, or perhaps the malic acid was not formed 

 by the dilute nitric acid ; for Berzelius, who feems not to 

 have been acquainted with this fad, found alfo, that when 

 10 



albumen tfras precipitated from its folution in acetic acid 

 by the nitric acid, the yellow precipitate was rendered gela- 

 tinous by wafhing, and foluble in water, like the compounds 

 of albumen with the other acids above-mentioned ; all which 

 compounds are probably fimilar to the above, and which 

 was confidered by Mr. Hatchett as gelatine. The acetic 

 acid readily diffblves albumen by the affiliance of heat, flrft 

 converting it, if previoufly coagulated, into a tremulous 

 jelly. The folution is colourlefs, and of a mawkifl\ and 

 nightly acid tafte. When fufficiently evaporated, it again 

 becomes gelatinous ; and when completely exficcated is a 

 tranfparent mafs wliich reddens litmus, but is' infoluble both 

 in hot and cold water, without a frefh addition of acetic 

 acid. Ammonia and prufliate of potafli produce from this 

 folution in acetic acid a whitifh precipitate. Alkalies alfo 

 produce a precipitate which is again diffolved on their 

 being added in flight excefs. Sulphuric, muriatic, and nitric 

 acids produce precipitates, which are compounds of the 

 albumen with the acid employed, the acid being in excefs ; 

 hence, if they are wafhed in water, as before obferved, they 

 become neutral, and capable of folution in water, hke 

 gelatine. 



Solutions of the different earths, and even fome of tlieir 

 falts, as alum, fulphate of magnefia, and filicated potafh, 

 were found by Dr. Thomfon to have no effeft upon albumen 

 when diffolved in water, in the proportion of one white of 

 an egg to a pint of water. The cafe, however, Was very 

 different with the metalhc falts and oxyds, mofl of which 

 were found to have a powerful efFeft upon it, efpecially the 

 fulphates, muriates, and nitrates of the metals, while the 

 prufliates, and one or two others, had no effeft. One of the 

 molt delicate tefts of albumen, according to Dr. Boftock, 

 is a folution of oxymuriate of mercury : a Angle drop of 

 this, let fall into water, containing only ^oVtt parts of its 

 weight of albumen, produces an evident milkinefs, and a 

 curdy precipitate falls. Heat renders the operation of this 

 teft more effeftual. Perhaps the teft of albumen leaft liable 

 to ambiguity, is that recommended by Berzelius above- 

 mentioned ; namely, the addition of the pruffiate of potafli to 

 a folution of albumen in acetic acid. Albumen is compofed 

 of hydrogen, carbon, oxygen, and nitrogen or azote, in the 

 proportions, according to the experiments of Gay Luffac 

 and Thenard, of 



Hydrogen 

 Carbon 

 Oxygen 

 Azote 



7.540 

 52.883 

 23.872 

 15.705 



100.000 



Albumen never exifts in an abfolutely pure ftate in animal 

 bodies, but is always combined with other animal matters, 

 and various falts. See Blooo and minimal Fluids. 



ALBURGH, in Geography, a town of America, in 

 Vermont, and county of Grand Ifle, containing 1106 inha- 

 bitants. 



ALBUS, in Commerce, a fmall coin and money of 

 account at Caffel, Cologne, and other places in Germany. 

 The whole principality of Heffe keeps accounts in rix- 

 dollars of 32 albufes, fubdivided into 9 pfenings, or I2 hel- 

 lers current. A fpecie rix-doUar is worth 42 1 Heflian 

 albufes. Coins in filver are, pieces of 8, 5^, 4, 2|, and 

 I3- albufes ; and in copper, pieces of i and 2 albufes. 

 Cologne keeps nceotmts in rix-doUars fpecie of 80 albufes, 



or 



