116 Progress of Foreign Science. 



and structure of the muscular fibre, known to chemists by the ex- 

 pressive name of fibrine. 



Such is the manner in which the materials of the blood are dis- 

 tributed ; and these gentlemen have repeated their observations 

 so many times during two years, that they entertain no doubts on 

 the subject. It perfectly explains the inutility of the attempts 

 made to insulate the colouring matter ; and affords almost a cer- 

 tainty that this object will never be accomplished. 



Three animal substances ought, therefore, to fix our attention 

 in the chemical study of the blood ; these are, the albumen of the 

 serum, the white globule, and the colouring matter which enve- 

 lops this. 



They ascertained by experiment that the coagulation of albumen 

 (white of egg,) takes place about 70° C. When once coagulated, 

 the albumen, viewed in the microscope, presents the same white 

 globules so often mentioned. The action of the voltaic pile clearly 

 shews the state of combination which exists between albumen and 

 the soda it contains. They ascribe the coagulation of albumen by 

 spirit of wine, to the affinity of this menstruum for the caustic 

 soda. They consider this as the most convenient method of ob- 

 taining albumen in a state of purity ; and on studying it under this 

 form, it is seen, by the action of different re-agents, to differ in no 

 respect from fibrine. Lastly, the action of acids on albumen falls 

 under the same head, although there are two modes of action to 

 be distinguished. 1, The saturation of the soda; 2. The action of 

 the acid on the albumen. The first cause explains the precipitation 

 of white of egg by most acids; the second permits us to conceive 

 why the phosphoric and acetic acids form an exception to this 

 rule. In fact, these two agents dissolve, or at least reduce, to 

 jelly, fibrine itself; and, consequently, must be very far from pre- 

 cipitating its alkaline solutions. 



The colouring matter of the blood has engaged the attention of 

 so many celebrated chemists, that they would long ago have ex- 

 hausted its history, had they not been misled by a physical cir- 

 cumstance of great simplicity. It is singularly divisible in water, 

 and passes even through filters ; but by means of the microscope, 

 its fragments are easily discovered, and they fall down or repose, 

 in the form of a red deposit, of considerable density. This pro- 

 perty of colouring water without disturbing its transparency, made 

 chemists believe that water could dissolve this substance, and they 

 subjected the red liquor to the action of reagents whose effects 

 have never been satisfactory. The colouring matter of blood ap- 

 pears to be formed of an animal substance in combination with the 

 peroxide of iron. Were we to abide by the experiments hitherto 

 made, we should believe that this matter is albumen ; but as only 

 a confused mixture of red matter has been operated ou of white 



