1038 EXPERIMENT STATION RECORD. 



The other three methods gave closely agreeing results and were about equally satis- 

 factory. The fluorid method is probably the quickest and most satisfactory in the 

 hands of beginners. For control purposes it is recommended to weigh first as car- 

 bonate and then convert into sulphate or fluorid. 



Determination of lime in soils, D. J. Hissixk (Chem. WeekbL, 3 (1906), pp. 

 73-78; abs. in Chem. Centbl, 1906, I, Xo. 11, p. 961).— Neubauer's method is recom- 

 mended. 



The analysis of foods. Simple and easy methods of detecting- adulteration 

 of food products and other domestic articles, C. Margeot (V analyse des aliments. 

 Recettes simples et faciles pour decouvrir toutes les falsifications des produits alimentaires 

 et autres objets domestiques. Paris: E. Flammarion, pp. 188). — As the subtitle states, 

 this volume gives simple directions for the detection of adulteration of food products 

 and other materials used in the home. The descriptive matter includes standards of 

 quality of staple articles of food, the principal methods of adulteration and sophisti- 

 cation which are likely to occur, and methods of detection of adulteration. 



The use of the immersion refractometer in food analysis, J. Hants and K. 

 Chocensky (Ztschr. Untersuch. Nahr. u. Genussmil., 11 (1906), Xo. 6, pp. 313-310, 

 fig m ^)._xhe experimental data described show that the immersion refractometer 

 may be used to determine the amount of caffein present in aqueous solution quickly 

 and accurately. 



Maple sirup and maple sugar investigations with particular reference to 

 the detection of adulteration, C. II. Jones ( Vermont Sta. Rpt. 1905, pp. 315-839).— 

 A number of samples of maple sugar and sirup, maple cream, and brown sugars were 

 examined with special reference to the amount and character of the ash present, the 

 malic acid value, the amount of precipitate obtained with lead subacetate, and other 

 characteristics, the object of the investigations as a whole being the detection of 

 adulteration, particularly with cane and beet sugar products. 



According to the author, the minimum standards which seem warranted when 

 applied to a filtered sirup weighing 11 lbs. to the gallon are not less than 0.50 per 

 cent total ash, not less than 0.15 per cent insoluble ash, not less than 0.40 per cent 

 malic acid value, nor less than 1.00 cc. for the lead subacetate precipitate. 



If an examination of an original sample shows that one or all of such salient fac- 

 tors are below the minimum, the samples should be boiled to a uniform basis of con- 

 centration and filtered. It would seem, the author states in effect, that a certain 

 minimum amount of ash can not be removed from pure maple sirup or maple sugar 

 made into sirup, by the ordinary methods of filtration, and that even slow and com- 

 plete filtering fails to remove sufficient ash from the pure goods to admit even a sus- 

 picion of adulteration. 



The ash of pure maple goods consists largely of carbonates of potassium and lime 

 with relatively small and varying quantities of sulphates and phosphates. The 

 determination of the sulphates, according to the author, is of use at times in detect- 

 ing adulteration since they are present in relatively large amounts in many commer- 

 cial brown, cane, and beet sugars. 



"The amounts of lime and potash also afford data useful in judging the purity of 

 suspected samples. Owing to the work involved these determinations are needful 

 only in important cases when other tests do not furnish convincing data. 



"It has been observed that the percentage of sulphates appears to be greater in 

 maple sirup than in maple sugar, although no explanation has been offered. In the 

 writer's opinion, it may be accounted for as follows: The percentage of ash, soluble 

 in water, is greater in sirups than in sugars. . . . This is due entirely to the larger 

 quantity of malate of lime (insoluble ash) in the sugar. As sulphates are found 

 largely in the soluble ash, they would therefore average greater on an ash basis in 

 sirups than in sugars. 



