306 THE CAUSE OF HEALING 



hundred grammes of sheep's suprarenal glands yields 

 about 4 grammes of dry extract. 



A series of jellies were prepared which contained 

 . 8 cc. of alkali solution (8 units) , variable quantities of 

 solutions of the extract, and they were always made up 

 to the total of 10 cc. with water. At first a 5-per-cent 

 solution of the extract was made ; and it was found that 

 if the jelly contained 1 cc. of this extract, very early 

 divisions can be induced in lymphocytes. With 2 cc. 

 later stages of mitosis will appear (figs. 100, 101) ; and 

 if instead of the 5-per-cent solution a 10-per-cent one 

 is made, even more marked divisions can be induced 

 by this fresh extract alone in the experimental ten 

 minutes. The best jelly to make in order to cause 

 suprarenal extract to induce divisions in lymphocytes 

 in the ten minutes is: 5 cc. of coefficient jelly, 1 cc. of 

 alkali solution, 2 cc. of a 10-per-cent solution of dried 

 suprarenal extract, and 2 cc. of water. By means of 

 this jelly advanced mitotic figures can be induced in 

 lymphocytes. 



So it was proved, therefore, that this extract of dead 

 suprarenal gland contains a substance which will cause 

 the divisions of lymphocytes. A fresh jelly was then 

 prepared the same as the last one, except that it had 

 added to it four more units of alkali solution. Now, as 

 we anticipated, the polynuclear leucocytes also divided 

 on the microscope slide (fig. 102). 



But the question was then asked, How was it that 

 the original extract, although it was not strong enough 

 to induce divisions by itself in ten minutes, did become 

 effective when it was decomposed by putrefaction ? It 



