1907.] PUBLIC DOCUMENT— No. 33. 85 



Special Chemical Work. 

 This division has devoted some time to a study of methods 

 used in chemical analysis, in co-operation with the Associa- 

 tion of Official Agricultural Chemists. The work under- 

 taken was as follows : — 



1. A comparison of the Kjeldahl, Kjeldahl-Gunning and 

 modified Gunning methods, for the determination of total 

 organic nitrogen. 



2. The determination of available organic nitrogen by the 

 neutral permanganate and by the alkaline permanganate 

 methods. 



3. A study of the Babcock asbestos, dish and sand, and 

 Gottlieb methods, Babcock centrifugal and Leach and Far- 

 rington modifications of the same, for the determination of 

 fat in sweetened and unsweetened condensed milk. 



4. Observations in the determination of lactose and su- 

 crose in sweetened and unsweetened condensed milk, by aid 

 of Fehling's solution, the copper being titrated with thio- 

 sulfate. 



5. Determinations of moisture, ash, protein, dextrose and 

 sucrose in massecuit, sugar and molasses. Considerable time 

 was spent in a special study of different methods for the ac- 

 curate determination of moisture in molasses, which has not 

 been reported ; it will be published when sufficient data have 

 been secured to warrant the making of positive deductions. 



6. Determinations of total, soluble and insoluble ash in 

 pure and adulterated maple sugar, as well as the alkalinity 

 of the soluble and insoluble ash. 



The results of the above work were presented to the asso- 

 ciation, and became a part of their yearly report. It was 

 carried out by Messrs. Holland and Smith, to whom due 

 credit should be given. 



In addition to the above, work is now in progress in deter- 

 mining the water and starch in 3G samples of potatoes. 



