Mat 2, 1913] 



SCIENCE 



677 



fuging the fat to the top as in the Babeoek test, 

 then drawmg oflE the acid-sugar solution through 

 a small glass stopcock fused on near the bottom 

 of the test-bottle. This is the essential modifica- 

 tion in this method. 



A new ice-cream modified test-bottle, graduated 

 to 25 per cent, for an 18-gram charge, is shown. 

 Eesults of 350 determinations on different ice- 

 creams show that results consistent with the Eoese- 

 Gottlieb ether extraction method are obtained, 

 though running 0.6 per cent. low. The residual fat 

 lost in the drained-off acid-sugar portion is shown 

 to average the same as that lost in the Babcock 

 test of cream. 



The maximum variation of the individual read- 

 ings compare favorably with those of the Eoese- 

 Gottlieb method. 



The modified method in detail with numerous 

 tables of data are given, also two figures of the 

 modified Babcock test and of the modified test 

 bottle. 



P. W. HoLTZENDOBFP : The Separation and Iden- 

 tification of the Permitted Coal-tar Colors in 

 Foods. 



The method is confined to the permitted colors. 

 Advantage is taken of difference in chemical com- 

 position and extraction by immiscible solvents to 

 effect separation. Identification tests are made on 

 the dry color and in aqueous solution, after well- 

 knovfn methods, particularly the reactions obtained 

 with concentrated HoSOi. 

 Arden E. Johnson and B. W. Hammar: Specific 



Seat Observations on Milk and Cream. 

 Arden E. Johnson and Eot E. Smith: A Ther- 

 mal Method for the Determination of Eatio of 

 Congealed to JJncongealed Moisture in Frozen 

 Soils. 

 A. McGiLL: Some Ph<ises of National Food Con- 

 trol. 

 A. E. Perkins: A Simple and Convenient Method 

 for Determining the Salt Content of Butter. 

 This paper describes a method for the deter- 

 mination of salt by titrating a solution of 5 or 

 10 grams of butter in 20 or 30 c.c. of commercial 

 acetone with silver nitrate, using potassium chro- 

 mate as an indicator. The author states that the 

 method yields results entirely comparable with the 

 longer volumetric or gravimetric methods formerly 

 used. 



Equal parts of commercial alcohol and ether 

 may be substituted for the acetone with equally 

 good results. 



A. E. Perkins: A Note Regarding an Absorption 



Tube and Beceiver used in the Kjeldahl Nitro- 

 gen Determination. 



The author states that successful use has been 

 made of a 2-inch glass funnel and glass jar with 

 straight sides used as the absorption tube and the 

 receiver, respectively. 



He states that the advantage is the large surface 

 of acid that is present for the absorption of 

 ammonia vapors, and very little bubbling occurs. 

 No trouble has been experienced with the acid 

 striking back towards the distilling flask. 

 C. S. EOBINSON and O. B. Winter : The Nature of 



Nitrogenous Compounds in Feat Soils. 



This paper takes up the study of the protein 

 content of peat soils. Van Slyke's method for the 

 determination of amino nitrogen is used to study 

 the amount of nitrogen converted into the amino 

 form under various conditions of acid and alkaline 

 digestion. About 27 per cent, of the total nitrogen 

 was converted into tlie amino form on heating 

 with 25 per cent, sulphuric acid 96 hours and 

 about 50 per cent, by heating with 5 per cent. 

 NaOH for 150 hours. 

 E. H. EOBINSON: Some Chemical Changes taking 



Place during the Embryonic Development of the 



Chicle. 

 S. H. Boss and N. Hendrickson : A Simple and 



Efficient 20° C. Bacteriological Incubator. 



A very satisfactory 20° incubator was made 

 from an ordinary refrigerator, size 20 in. X 29 in. 

 X 46 in., by installing two heating coils, 0.2 

 ampere, and a disc type thermoregulator in the 

 refrigerating compartment. The thermoregulator 

 actuated a circuit breaker and connection was 

 made to a lighting circuit. With care in regu- 

 lating the amount of ice the temperature was 

 easily maintained between 19.5° and 20.5° C. 

 J. F. Snell: The Detection of Adulteration in 



Maple Syrup and Sugar. 

 H. V. Tartar and B. Pilkington: A Comparative 



Study of the Composition of Sops Grown in 



Different Parts of the World. 

 H. V. Tartar and L. A. Bundy: A Note on the 



Soluble Arsenic in Mixtures of Lead Arsenate 



and Soap. 

 J. BosLEY Thomas and Edgar A. Sandman: 



Some Besults of the Sypochlorite Disinfection 



of the Baltimore City Water Supply. 



The period covered by this report extends from 

 January 1 to December 31, 1912. Calcium hypo- 

 chlorite was applied at the effluent of the im- 



