THE CHEMISTRY OF VENOMS. 11 



settles to the bottom of the glass, leaving in the course of a few hours a per- 

 fectly clear supernatant liquid. If sufficient water has been added at first, the 

 addition of more distilled water to the supernatant liquid will not cause any 

 further precipitate. 



The precipitate is now collected and repeatedly washed with distilled water and 

 decanted until the wash-water yields no proteid reaction. 



The following gives the results of some of the many reactions upon the addition 



of the various reagents used ■ — 1 



Decided reactions with the usual proteid tests. 



Boiling — causes coagulation. 



Sodic chloride (0 75 per cent.)— slightly soluble. 



'10 " )— soluble, forming a turbid solution ; the solution is not precipi- 

 tated by carbonic acid 2 nor by the addition of ether. 



boiling the solution causes coagulation. 



the solution is precipitated by saturation with sodic chloride. 



Carbonic acid* — soluble. 



Sodic carbonate — very soluble; solution not precipitated by carbonic acid. 



Hydrochloric acid (0 i per cent.)— very soluble. 



Metaphosphoric acid — insoluble. 



Orthophosphoric acid — dissolves. 



Sodic melaphosphate — insol uble. 



Sodic orthophosphate — very soluble. 



Potassic sulphate — very soluble. 



Calcic chloride — very soluble. 



Acetic acid (5 per cent.) — very soluble. 



Acetic acid {glacial) — very soluble. 



Coagulation occurs at about 64-73° C. 



Since this body is precipitated by saturation with sodic chloride, and dissolves 

 with difficulty in a 0.75 per cent, solution of sodic chloride, it seems more akin 

 to myosin than other of the globulins. 



The Copper-venom-globulin. — After the separation of the water-venom-globulin 

 the filtrate gives well-marked proteid reactions and decided coagulation by boiling. 

 If now a few drops of cupric sulphate (10 per cent.) be cautiously added a second 

 precipitate will occur, and which can be separated as in the previous instance. In 

 adding the cupric sulphate great caution must be exercised lest too much be added 

 with the result of a complete or partial re-solution of the precipitate. 



The precipitate is sometimes comparatively slight at first, increasing upon stand- 

 ing, and complete within about twenty-four hours. The clear filtrate should give 

 no precipitate after the addition of a small amount of the copper solution and after 

 standing twenty-four hours longer. 



1 In all of these reactions with the globulins, unless otherwise apparent, about 1 c. c. of the 

 suspended globulin in distilled water was placed in a small test-tube, and from one to two drops of 

 standard laboratory solutions of reagents were allowed to run down the inside of the tube. 



We have made a large number of tests with various reagents, and from this number have selected 

 only such as will serve us some purpose in distinguishing these different bodies. 



2 Where carbonic acid is used in these tests we have reference to the super-saturated carbonic 

 acid water (soda water) of commerce. 



