1911.] PUBLIC DOCUMENT — No. 31. 233 



to twenty-two hours. This i)rol)ably gives results too low, but 

 iliis method seemed the l)e>t with the facilities at hand. Insol- 

 uble solids were deternuned by washing 25 grams with 500 

 cubic centimeters hot water on muslin filters, and drying on 

 pumice fourteen hours at 95° to 98°. The reducing sugars 

 were determined by reducing Fehling's solution and weighing 

 the precipitate as cuprous oxide ; the sucrose, by means of the 

 ])olariscope; and malic acid, by titrating with N/10 alkali with 

 ])henolphthalein as an indicator. 



Most of the analyses were made during the winter of 1910-11. 

 All samples, save those from Amherst, were shipped direct to 

 cold storage in Holyoke, Mass., and transferred to Amherst a 

 few samples at a time, as needed, where they were held as cool 

 as possible. The Andierst samples, as well as all those of 1910, 

 were kept in an excellent cellar storage at the college. The lab- 

 oratory numbers were given in order of analysis, work being 

 begun with No. 1 in November. 1910, and completed about 

 ]\rarch 1. 1911. The samples of 1910 were analyzed in March, 

 and while no notes of their condition were taken, it can be said 

 that they were in excellent condition, most of them eating ripe. 



These analyses form the basis for the chemical side of the 

 discussions of the different varieties in this ])aper. There are, 

 however, certain questions not dealt with elsewhere which may 

 receive consideration at this point. 



Nearly all the differences in analyses between the different 

 samples, aside from those fairly attril)utable to the unavoidable 

 errors of sampling and analysis, can be traced to one of two 

 causes: (1) varietal differences; these are brought out in Table 

 1; (2) those attributable to different stages of maturity of the 

 fruit. The chemical changes occurring in the growth and ripen- 

 ing of the apple are clearly brought out in the work of the 

 Bureau of Chemistry, reported in Bulletin 94 of the Bureau, 

 and the reader is referred to that publication for a discussion 

 of this question. During the past winter analyses were made of 

 four samples in November and again in Februnrv. These 

 were : — 



