6 ENOLOGICAL STUDIES. 



The average sugar content of these varieties is 11.40 per cent, 

 about 1 per cent below the general average of our best American 

 apples, and the juice on which the experiment was made was even 

 poorer, as shown by the following determinations, also made by Mr. 

 Gore: Specific gravity, 1.0497; total sugar, 10.15 per cent; total acid 

 as malic, 0.287 gram per 100 cc. Frequently specific-gravity read- 

 ings of the juice as expressed at the cider mill -at Nehawka were as 

 low as 1.045, and the acid was quite uniformly low. The fruit used 

 for the experiment was mixed, but was chiefly Grimes Golden. 



NOTES ON CONDITION OF SAMPLES DURING FERMENTATION. 



On September 4, 1906, juice from the mill having at 71 F. a spe- 

 cific gravity of 1.045 was put into flasks and sterilized by boiling 

 fifteen minutes in a water bath. This was cooled, and at 11 a. m. 

 four pint flasks were sown with yeast, one each with Nos. 8, 53, 66, 

 and 73, respectively. These were put in the rooms having a temper- 

 ature of 70.7 F. 



September 5. Fermentation commenced in the flasks sown with 

 yeast. Temperature of fermentation room, 72 F. 



September 7, 7 a. m. All flasks have fermented strongly, and 

 heavy foam rests on the surface, except No. 66, which is bare, and 

 foam is breaking up on No. 8. Fermentation room, 79 F. all day. 



Septembers. Fermentation room 74 F. at 7 a. m.; 80 F. at 

 5 p. m. 



September 10, 8 a. m. Fermentation room 76 F. 



September 11, 8 a. m. Fermentation room at 78 F. Weather has 

 been very warm, temperature running up to from 95 to 98 in the 

 shade each day. 



September 12, 8 a. m. Fermentation room 66 F. Rained and 

 turned cooler. 



September 13. Fermentation room 60 F. at 8.30 a. m. Filled 

 four 30-gallon barrels with fresh must and sowed at 11 a.m. with 

 yeasts Nos. 8, 53, 66, and 73, as before, 1 pint of each culture 

 being used. Room temperature was 66 F., juice temperature 62.6 

 F. in barrels. Marked each cask with number of yeast used in it. 

 Cask No. 8, specific gravity 1.048; No. 53, 1.049; No. 66, 1.049; and 

 No. 73, 1.049. 



This juice is chemical sample No. 55 of Mr. Gore's notes, and the 

 differences in specific gravity are explained by the fact that his 

 determinations were made on a pyknometer and those here given on 

 a spindle. 



5 p. m. Fermentation room 68 F. 



On application to Wm. B. Alwood, Stonehenge laboratories, Charlottesville, Va., a 

 circular giving further details in regard to these yeasts may be obtained. 



