12 HANDBOOK FOR BIO-CHEMICAL LABORATORY. 



treated with MgS0 4 in substance until 100 c.c. of the liquid 

 contains about 50 grms. of the salt. The so-called paramyosin 

 or musculin separates. The filtered liquid is now treated 

 with magnesium sulphate until each 100 c.c. of the liquid 

 holds 94 grms. MgS0 4 in solution. The myosin which now 

 separates is filtered, dissolved in water by the aid of the re- 

 tained salt, precipitated by diluting with water, and, when 

 necessary, purified by redissolving in dilute salt solution and 

 precipitating with water. (Halliburton.) 



2. Myosin may also be prepared by treating finely chopped 

 meat, which has first been soaked in cold water until the 

 muscles are white, with a 10-20$ ammonium-chloride solu- 

 tion, allowing to stand for a few hours, stirring now and then. 

 Filter this solution off and dilute with about 20 vols. water. 

 The myosin separates in flakes which gradually settle to the 

 bottom. This is washed 3 to 4 times by decantation, but not 

 oftener, as then the myosin becomes insoluble. Dissolve now 

 in ammonium-chloride solution and the myosin obtained 

 therefrom, either by reprecipitating by diluting with water, or 

 by removing the salt by dialysis. (DanileivsJcy.) 



Properties. Myosin has the general properties of the 

 globulins. It is completely precipitated by saturating with 

 NaCl, also by MgS0 4 , in a solution containing 94$ of the salt 

 with its water of crystallization. Like fibrinogen it coagulates 

 at 56 C. in a solution containing common salt, though the 

 coagulation temperature may vary for myosins of different 

 origin, and also for the same myosin in different salt solutions. 

 It is soluble in dilute alkalies. Myosin decomposes hydrogen 

 peroxide. 



Ovo-Yitellin. 



Preparation. Shake the yolks of two eggs with 200 c.c. acid- 

 free ether in a stoppered cylinder, then add 5 c.c. alcohol. A 

 sticky, stringy precipitate will be formed. Remove the ether 

 as well as possible and add 100 c.c. of a 10$ common salt 



