110 MR. E. SCHUNCK ON THE ACTION OF 



a substance altogether sui generis. I have given it the name 

 of Erythrozym, 



In the paper just mentioned I have stated, that "if this 

 substance be mixed with water, and the mixture be allowed 

 to stand for a length of time in a warm place, signs of a 

 more active process of fermentation begin to show them- 

 selves, especially in summer weather; bubbles of gas are 

 given off, and a peculiar smell is emitted, which, though dis- 

 agreeable, cannot exactly be called putrid. During this pro- 

 cess, which is evidently one of putrefaction in the stricter 

 sense, the erythrozym loses its sliminess, and is converted 

 into a red flocculent mass, which may easily be separated by 

 filtration from the liquid. The latter is clear, colourless, and 

 quite neutral. After erythrozym has passed through this 

 second stage of decomposition, its power of decomposing 

 rubian is found to have lost much of its intensity. It is 

 during the first period of its decomposition, when no apparent 

 change is taking place, that this power is most energetically 

 exerted. During the second, or more strictly putrefactive 

 stage, it acquires, however, the property of decomposing 

 sugar. If erythrozym be mixed with a solution of cane 

 sugar, and the mixture be allowed to stand for a considerable 

 time until gas begins to be disengaged, the solution acquires 

 by degrees a decided acid reaction." The great interest at- 

 taching to bodies of this class induced me to examine this 

 action of the ferment on sugar more minutely, and I have 

 now the honour of laying the results of my investigation be- 

 fore the Society. 



In order to obtain the ferment for the purpose of decom- 

 posing sugar, it is not necessary to prepare it by precipitation 

 with alcohol, as I recommended in my paper on Rubian, nor 

 to pay much attention to its complete purification. I found 

 that the following method of preparation yielded a product 

 perfectly well adapted for the purpose. A quantity of mad- 

 der (French being the kind employed) having been placed on 



