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with eight or ten parts of water. The nitricacid on the other hand much impairs the finecolour and gives it a shade of brown. Theacetic acid acts as the muriatic, but with stillmore distinction between the effect of reflectedand transmitted light. With the tartaric acidthe solution inclines to scarlet.

Both the caustic and carbonated alkalies formdeep red solutions of this colouring matter,which are very permanent. Soda gives a colourmore inclining to a crimson, and ammonia stillmore. When these solutions are supersatu-rated with nitric acid the colour passes intobright yellow.

The author then endeavoured to combinethis colour with some of the common mordants.Alumine would not answer, for though itextracted the colour pretty well, it becamebrown instead of retaining its original red.The solutions of tin succeeded scarcely better.Those of mercury answered the best. Whencorrosive sublimate is added to the aqueoussolution of the condensed colouring matter, itstint is instantly brightened, and it becomesslightly turbid from the deposition of a littlealbumen. If this be immediately filtered, theclear liquor gradually deposits a deep red in-soluble precipitate which carries down thewhole of the colour. Woollen cloth firststeeped in corrosive sublimate and then in awatery solution of the colouring matter ofblood, acquires a permanent red tinge un-alterable by soap, which possibly may be ofuse in dyeing.

We shall conclude this article with a veryshort abstract of the most original parts, in. anelaborate analysis of blood made by professorBerzelius , being one of a series of investigationson animal fluids, first published in this countryin the Medico-Chirurgical Transactions, vol. 3.

The blood selected for experiment was. thatof the ox.

Blood, he observes, may be regarded as aliquid holding a colouring matter suspendedin it, but not dissolved.

The only practicable way of separating theconstituent parts of blood is that of coagulation,as usually employed, though this is imperfect,as much of the serum remains attached to thered globule in the coagulum.

The crassamentum contains the fibrin andthe colouring matter, which are separable bywashing, in the way often described.

Fibrin . No part of this is soluble in coldwater, but a portion is extracted by longboiling, which when the liquor is evaporated

gives a white, dry, friable residue, Soluble incold water, and of an agreeable taste like broth.Fibrin , when long boiled, loses the property ofbeing soluble in acetic acid.

Alcohol digested with fibrin changes it to anadipocerous or fatty matter, soluble in thealcohol, and separable by water. This fattymatter is formed in the process, and does notexist as such in the recent fibrin.

Ether has a similar effect with alcohol, andthe fatty matter is more abundant and morenauseous.

Concentrated acetic acid immediately softensfibrin, renders it transparent, and when heated 1dissolves it into a tremulous jelly, which issoluble in warm water. When this solution isevaporated to dryness it retains sufficient acidto redden litmus, but will not redissolve with-out more acid. Sulphuric, nitric, and muriaticacids, give a precipitate with this solution com-posed of fibrin and the acid employed, whichwhen washed with water loses a part of theacid, and the remainder dissolves in morewater. More acid will again give a precipitatewith the latter solution, so that fibrin with acertain portion of acid is soluble in water,, andwith an excess of the same acid becomes in-soluble. Alkalies also give a precipitate' withthe solution of fibrin ill acids, and ail excess ofalkali redissolves it.

Weak muriatic acid, digested with fibrin,hardens and shrinks it, and long boiling withwater at last converts this to a soluble gela-tinous mass. Some azotic gas is given out.This solution is again precipitated by an excessof the acid.

Concentrated muriatic acid decomposes fibrinwhen boiled upon it, and gives a violet colouredsolution..

Sulphuric acid, when diluted, has a similareffect on fibrin with muriatic acid; and likethis, produces two compounds with it, oneinsoluble, in which- the acid is in excess;,and the other, where the acid is scarcely, pre-dominant, soluble in water. Nitric acid of1.25 sp. gr. digested with fibrin turns it yellow,,and forms a small quantity of. fat on thesurface. Pure azotic gas is given, out. Aftera day’s digestion the fibrin becomes a yellow-powder, which turns to orange by washing,and is less acid, but still remains enough toredden litmus. This substance, first discoveredby Fourcroy and Vauquelin , was supposed bythem to be a new acid, and called by. themAeidc Jaune , but professor Berzelius considersit as a compound of fibrin, with nitric or nitrous