THE BLOOD. ' 13 



these experiments, as well as some others, were not made so 

 much with a view of any immediate application to medicine, 

 as to determine the properties of the blood chemically; for, 

 having set out with a persuasion, that a more particular ac- 

 quaintance with the properties of this fluid was necessary be- 

 fore we could arrive at the knowledge of some of the animal 

 functions, such as the manner in which the bile and other se- 

 creted fluids are formed, I therefore was anxious to throw some 

 more light on this. subject. With this view I have made some 

 experiments even on living animals, being convinced that my 

 inquiries would not otherwise be satisfactoiy. 



When blood is thus kept fluid by Glauber's salt, it still re- 

 tains its property of being coagulable by heat, and by other 

 substances as before, air excepted. This method of keeping 

 the blood fluid may therefore be useful, by affording an oppor- 

 tunity of making some experiments upon it, which we could 

 not otherwise do from its coagulating so soon when taken from 

 the vessels. 



This property of one of the neutral salts has been long 



will hasten coagulation, though they prevent it in greater quantity. 

 Dr. Simon c mentions, quoting Hamburger, that carbonates and acetates, 

 in all degrees of concentration, prevent the coagulation of the blood ; 

 while the sulphates, tartrates and borates, in strong solution retard 

 and in weak solution accelerate coagulation. In ray experiments' 1 with 

 solutions of common salt, five and ten grains to an ounce of water, co- 

 agulation was somewhat retarded, but most so by the weaker solution ; 

 and an ounce of mucilage, having either five or ten grains of salt dis- 

 solved in it, likewise retarded coagulation, though less so than the mu- 

 cilage without the salt. The contraction of the clot was generally much 

 diminished by the aqueous saline solutions, but not by the mucilaginous 

 saline solutions. Mr. Prater observed that either a saturated or a very 

 weak solution of common salt, prevents the contraction of a portion of 

 muscle removed from an animal just killed, and that the addition of 

 water does not restore the contractile property. Mr. Ancell e has given 

 a copious table of the effects of various substances on the coagulation 

 of the blood. 



The effect of neutral salts in preserving the fluidity of the blood is 

 probably dependent on the solvent power, which M. Denis f has shown 

 them to possess over the fibrin. But this requires further inquiry. 8 



c Animal Chem. i, 116, tr. by Dr. Day, e Lectures on the Blood, Lancet, vol. i, 

 8vo, Lond. 1845. 1839-40, p. 522. 



d Edin. Med. and Surg. Jouru. vol. Ixiv, f Essai sur le Sang, 8vo, Paris, 1838, 

 370. Exp. 20-28. pp. 71-2. 



" See Notes LVI, xu, XLIV, xvm. 



