CHOLE8TEBINE. 269 



is not entirely settled. It is stated that the biliary salts have 

 the power of holding it in solution in the bile, and that the 

 small amount of fatty acids contained in the blood hold it in 

 solution in that fluid ; but direct experiments on this point 

 are wanting. In the nervous substance and in the crystalline 

 lens, it is united " molecule d molecule " to the other elements 

 which go to make up these tissues. After it is discharged 

 into the intestinal canal, when it is not changed into sterco- 

 rine, it is to be found in a crystalline form ; as in the meco- 

 nium, and in the faeces of animals in a state of hibernation. 

 In pathological fluids and in tumors, it is found in a crystal- 

 line form, and may be detected by microscopic examination. 



Cholesterine is usually described as a non-nitrogenized 

 principle, having all the properties of the fats, except that 

 of saponification with the alkalies. Its chemical formula is 

 given as C 26 H M O. It is neutral, inodorous, crystallizable, 

 insoluble in water, soluble in ether, very soluble in hot alco- 

 hol, though sparingly soluble in cold. It is inflammable, 

 and burns with a bright flame. It is not attacked by the 

 alkalies, even after prolonged boiling. When treated with 

 strong sulphuric acid, it strikes a peculiar red color, which 

 is mentioned by some as characteristic of cholesterine. We 

 have found that it possesses this character in common with 

 the so-called seroline. 1 



Cholesterine may easily and certainly be recognized by 

 the form of its crystals, the characters of which can be made 

 out by means of the microscope. They are rectangular or 

 rhomboidal, exceedingly thin and transparent, of variable 

 size, with distinct and generally regular borders, and fre- 

 quently arranged in layers, with the borders of the lower 

 strata showing through those which are superimposed. This 

 arrangement of the crystals takes place when cholesterine 

 is present in considerable quantity. In pathological speci- 



1 This similarity in the reactions of cholesterine and seroline with sulphu- 

 ric acid is mentioned by Berard (Cours de physiologie, Paris, 1851, tome iii., 

 p. 117). 



