THE FERMENT OF MADDER ON SUGAR. I 1 1 



a calico strainer, water tieated to about 100° F. is poured on 

 it in the proportion of about four quarts of water to every 

 pound of madder. To the dark reddish-brown liquid there is 

 now added a small quantity of muriatic acid. This produces 

 a brown flocculent precipitate, wliich is allowed to settle, and 

 after the liquid has been decanted, it is washed with a quan- 

 ti^ of fresh water, the process being repeated until the 

 excess of acid has been removed, after which the precipitate 

 is collected on a calico strainer. After the water has run off, 

 there is left on the strainer a thick brown pulp. This pulp 

 contains, besides erythrozym, small quantities of pectic acid, 

 colouring matter &c., but these impurities are of no material 

 consequence as regards the process of fermentation. It differs 

 from the erythrozym prepared by precipitation with alcohol 

 in containing no lime or other base, the latter having been 

 removed by the acid used for precipitation. In my experi- 

 ments, however, I always added a certain proportion of lime 

 water to the solutions to be fermented, as I found that the 

 fermentation was much promoted by this addition. 



The bulk of my experiments was made with cane sugar, 

 but I have also subjected grape and milk sugar to the same 

 process of decomposition. In operating on cane sugar I pro- 

 ceeded in the following manner. The sugar having been 

 dissolved in water, I added to the solution for every pound 

 of sugar taken about four quarts of the brown pulp, prepared 

 as just described, and a sufficient quantity of lime water to 

 change the colour of the ferment from brown to dark purple, 

 and to cause a slight alkaline reaction in the liquid. The 

 whole having been well mixed, was left to itself. The ves- 

 sels which I employed for conducting the operation in, were 

 large earthenware mugs. In warm summer weather, pro- 

 vided the quantity of materials taken was not too small, the 

 fermentation generally commenced on the succeeding day. A 

 copious disengagement of gas took place, and continued for 

 a number of days. The bubbles of gas, in rising, formed. 



