AtJGTTST 17, 1906.] 



SCIENCE. 



195 



borate in borate mud. The colemanite is 

 sent to Bayonne, N. J., and converted into 

 borax. The borate mud is treated at 

 Daggett with sulphur dioxid and the boric 

 acid crystallized out and shipped. In 

 Tuscany the boric acid vapors are passed 

 into water which is then evaporated. The 

 vapors from driven wells have a pressure 

 sometimes of nine atmospheres and after 

 purification are used for driving steam- 

 ngines. Nearly pure ammonium sulphate 

 is also produced. 



AGRICULTURAL AND SANITARY CHEMISTRY. 



E, B. Voorhees, chairman. 



The Improved Refractometer Slide Rule 

 and its Application: Albert E. Leach 

 and Hermann C. Lythgoe. 

 The refractometer slide rule was first de- 

 scribed in the Jour. Am. Chem. Soc, in 

 1904. Since then it has been somewhat 

 improved and is now on the market. It 

 is designed for the use of oil and food 

 chemists who have occasion to employ the 

 butyro or the Abbe refractometer. It 

 readily converts indices of refraction 

 (which the Abbe instrument reads directly) 

 into degrees on the butyro-refractometer, 

 and vice versa. It also enables one to 

 transfer scale readings or refractive indices 

 taken at any temperature into their equiva- 

 lent at any other, thus avoiding trouble- 

 some calculations. 



Comparative Effect of Organic and Min- 

 eral Matter in Soil-extract Cultures: 

 Oswald Schreiner. 



A series of experiments with wheat and 

 other seedlings is reported in which the 

 effect of the organic and inorganic con- 

 stituents of the soil solution and of or- 

 ganic manures are studied. It is shown 

 that the toxic effect of certain soil extracts 

 is not entirely overcome by fertilizer salts, 

 but is more markedly affected by organic 

 substances, such as pyrogallol, the organic 



matter from ordinary stable manure, etc., 

 as well as by treatment with certain other 

 non-nutrient substances, or even by mere 

 boiling of the extract, indicating the pres- 

 ence of volatile or thermolabile organic sub- 

 stances. Results are obtained by separating 

 the organic and inorganic portions of a 

 stable manure extract and studying the 

 eff'ect of the various fractions on wheat 

 seedlings. The results show that the or- 

 ganic substances play a very large part 

 in the effectiveness of the extract, and more 

 especially through an action other than 

 that of nutrition. 



Chemical and Bacteriological Factors in the 

 Am.monification of Soil Nitrogen: Jacob 



G. LiPMAN. 



It is well known that organic nitrogen, 

 either as applied in manures and fertil- 

 izers, or as forming a part of the soil 

 humus, is utilized to an unequal extent in 

 different soils. Since the crops growing 

 on any soil do not derive their nitrogen 

 food directly from the nitrogenous organic 

 compounds, but make use of them only 

 after they are changed into more simple 

 substances in the processes of decay, it 

 follows that the unequal utilization of the 

 organic nitrogen, in different soils, is inti- 

 mately related to the quantitative and 

 qualitative differences in the development 

 of certain classes of soil organisms. On 

 the other hand, the soil bacteria are them- 

 selves influenced in their growth by the 

 chemical and physical constitution of the 

 soil ; and the simplification of organic com- 

 pounds in arable lands is, therefore, a func- 

 tion of both chemical and bacteriological 

 activities. It is shown that when 100 c.c. 

 of a ten per cent, solution of peptone is 

 inoculated with ten grams of fresh soil 

 the rapid transformation of the peptone 

 nitrogen takes place. On distillation with 

 excess of magnesia a large portion of this 

 peptone nitrogen distils over as ammonia. 



