308 



SCIENCE 



[N. S. Vol. XXXI. No. 791 



The Improvement of Analytical Processes: W. D. 



RiCHAEDSON. 



The Cost of Available Nitrogen in Commercial 

 Fertilizers: E. B. Vooehees. 



Bacteriological Methods for Determining the 

 Available Nitrogen in Fertilizers : J. G. Lipman. 



Notes on the Recovery of Waste Platinum: A. W. 

 Blaie. 



MetlMd and Materials used in Soil Tests: H. A. 

 Huston". 



Accuracy in Taking and Preparing Mixed Fer- 

 tilizer Samples: F. B. Porter. 



The Determination of Inferior Ammoniates in 

 Commercial Fertilizers : John P. Street. 



Reports of Committees: Paul Rudnick, for the 

 Committee on Nitrogen; G. A. Farnham, for the 

 Committee on Phosphoric Acid; J. E. Breeken- 

 ridge, for the Committee on Potash; F. B. 

 Veiteh, for the Committee on Iron and Alu- 

 minum. 



DIVISION or agricultubal and food chemistry 



W. D. Bigelow, Chairman 



W. D. B. Penniman, Secretary 



Analyses of Maize Products: Edward Gudeman. 



Analyses of maize products during the last five 

 years, showing changes in composition of these 

 products, especially as to ash, acidity, sulphites, 

 arsenic and metallic impurities. Discussion of 

 the effect of federal and state food acts on the 

 composition of these products. 

 The Influence of Microorganisms upon the Quality 



of Maple Syrup: H. A. Edson. 



Studies upon the microscopic flora of maple sap 

 during the past three years have shown that the 

 sap within the vascular bundles of the tree is 

 free from microscopic organisms, but that the tap 

 hole, spout and bucket afford favorable lodging 

 places for the development of microscopic life. 

 With the advance of the season as the days be- 

 come warmer and the freezing nights less frequent 

 and less severe, yeasts, mould spores and bacteria 

 appear in the sap in increasingly great numbers. 

 By isolation and inoculation experiments specific 

 groups of organisms have been shown to be the 

 cause of the various types of abnormal sap char- 

 acteristic of the late runs, such as green, red, 

 milky and stringy sap. Inoculations with pure 

 cultures in first run material yield syrup of in- 

 ferior color and flavor such as is frequently pro- 

 duced from the last run. 



Sap of the last run when drawn under condi- 

 tions to exclude heavy inoculations with micro- 



organisms yields syrup of superior color and 

 flavor which is in striking contrast to that pro- 

 duced from sap drawn in the usual manner from 

 the same tree at the same time. 

 Analyses and Composition of Milk and its Prod- 

 ucts: Edward Gudeman. 



Analyses of milks from different localities and 

 at different seasons. Discussion of change of 

 ratio between fat and solids not fat, and influence 

 on composition of concentrated milk products, 

 evaporated and condensed milks and milk pow- 

 ders. Influence of heating milks of various com- 

 position during pasteurization, sterilization and 

 concentration. 



The Composition of Milk: Hermann C. Lythgoe. 

 Analyses of known purity samples of milk show 

 that the milk sugar is practically constant while 

 the other constituents are variable. This fact may 

 be used in detecting skimming as well as watering. 

 After making the fat and total solids determina- 

 tions the proteids may be calculated from either 

 by Van Slyke's or Olson's formulse, respectively. 

 If the milk has been skimmed the calculated pro- 

 teids will be too low and if the sugar is calculated 

 by difference (assuming an ash content of 0.7 

 per cent.) it will be too high. Experience has 

 shown that these calculated figures for milk sugar 

 vary between 4.2 per cent, and 4.8 per cent, in 

 pure milk. If the milk has been watered they 

 will be low, while if the samples have been 

 skimmed the calculated sugar will be high. 

 Some Applications of Electricity to Apparatus 

 and Laboratories for Water Analysis: Ellen 

 H. Richards. 



The advantage of using electricity as a source 

 01 heat for making distillations, evaporations and 

 running ovens and incubators is pointed out. The 

 tungsten lamp is useful as a uniform source of 

 light for color determinations. Electricity makes 

 possible the use of the ventilating fan and the 

 vacuum cleaner. 



It is estimated that electricity is economical 

 for laboratory uses if it can be had at a cost of 

 four cents per kilowatt hour. The cost may be 

 reduced to this figure by any establishment using 

 exhaust steam for heating. 



It is so great a saving of labor and adds so 

 much to the general efficiency of the laboratory 

 and accuracy of its results, that it can not be 

 considered dear at twice that cost. 

 Pentosans in Soil: Oswald Schreineb and Ed- 

 mund C. Shobey. 

 Nearly all soils when treated with boiling 12 



