1920.] PUBLIC DOCUMENT — No. 31. 19a 



A description of the Massachusetts bomb calorimeter was 

 pubHshed in the "Chemical and Metallurgical Engineering" 

 of August, 1919. 



The work of the previous year on cranberries has been 

 continued and brought to a conclusion by the preparation of 

 two papers, one on the chemical changes that occur in the 

 fruit while in storage, and the other on the rate of respiration 

 of cranberries at different temperatures. These papers were 

 read at the annual meeting of the American Chemical Society, 

 and are now" embodied in the manuscript for a station bulletin. 



In the pursuit of the investigation of the soil of the plots of 

 Field A, which receive sulfate of ammonia, it was found that 

 the conditions of 1910 and 1911 were repeating themselves, 

 apparently because of the dry weather during May and June. 

 Where lime had not been applied, positive quantities of soluble 

 salts of manganese were found, corn plants were stunted and 

 showed noticeable reactions for manganese in their ash, and 

 clover and grass seed either would not germinate or died soon 

 after germination, leaving a barren surface. Where lime had 

 been applied, whether six years previously or this spring, no 

 trace of soluble manganese salt was found and no noticeable 

 injury to vegetation was observed. 



Mr. Jones has done much work on apple jelly in co-operation 

 with the department of horticultural manufactures. His work 

 has developed the need for a thorough study of the physico- 

 chemical properties of fruit jelly, and the relations to each 

 other of the acid, pectin, sugar and water, before jelly making 

 can become anything more than an empirical process. 



A second experiment has been completed on the protein 

 requirement of growing calves, in co-operation with the agri- 

 cultural committee of the Council of National Defense. It 

 was begun in January, 1919, and completed in July. Eight 

 grade Holstein calves were divided into two groups of four 

 each, and fed on a high and low protein diet. The minimum 

 protein ration was somewhat higher than that fed the preceding 

 year. Digestion experiments were made from time to time as 

 the experiment progressed, which included the nitrogen balance. 

 In this trial both groups made substantially the same average 

 growth. This work was in charge of Mr, C. L. Beals, who 



