310 



SCIENCE 



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



The Composition of So-called Temperance Beers: 



H. E. Barnard. 

 The Efficiency of Land Plaster in Preventing the 



Loss of Ammonia in Manures: Wilfred W. 



Scott. 



biological chemistkt section 



In Joint Session with the American Society of 



Biological Chemists 



S. C. Prescott, Chairman 



The Phosphorus of the Flat Turnip: Buet L. 



Haetwell and Wilhelm B. Quantz. 



It was found that the percentage of phosphorus 

 in the dry matter of flat turnips was influenced 

 by the amount of available phosphorus in the soil 

 upon which the crop was grown. This led to the 

 attempt to ascertain if any particular class of 

 the phosphorus compounds was influenced prin- 

 cipally. 



About 10 per cent, of the phosphorus of the 

 dry turnip was soluble in 95 per cent, alcohol, 

 and about 70 per cent, was dissolved subsequently 

 in 0.2 hydrochloric acid. Fifty to 70 per cent, of 

 the phosphorus in this extract was precipitable 

 by a molybdenum mixture containing only a small 

 amount of free nitric acid. In fresh turnips 

 about 80 per cent, of the total phosphorus was 

 foimd in the somewhat colloidal aqueous extract, 

 and over four fifths of this was directly precipi- 

 table by magnesium oxid and by the official mix- 

 tures of molybdenum and magnesium. 



Nearly all of the phosphorus in turnip juice 

 passed through a dialyzer. When added to a 

 standard solution of sodium phosphate, the col- 

 loidal matter from within the dialyzer interfered 

 with the complete precipitation of the phosphorus 

 by the molybdic method. Hydrochloric acid added 

 to turnip juice itself to the extent of 0.2 per cent, 

 made it possible, after filtration, to precipitate 

 nearly all of the phosphorus directly from the 

 filtrate. Practically no phosphorus in phytin was 

 present in the juice. It appears as if four fifths 

 of the phosphorus of fresh fiat turnips is in sol- 

 uble compounds and exists mainly as so-called 

 inorganic phosphorus. 



Ratio of Plant Nutrients as affected hy Harmful 

 Soil Compounds: Oswald Schkeinek and J. J. 

 Skinner. 



Results of a comprehensive study of culture 

 solutions with and without dihydroxystearic acid, 

 a harmful compound isolated from soils, were 

 reported. The culture solutions comprised all 

 possible ratios of the three principal fertilizer 



elements : phosphate, nitrate and potassium, 

 varying in 10 per cent, stages. The culture solu- 

 tions were changed every three days and analyzed, 

 the remaining composition and ratio of the above 

 fertilizer elements being thus determined. In this 

 way the effect of the plant and of the dihydroxy- 

 stearic acid on the composition and ratio could be 

 determined. The triangular diagram is used in 

 this work and makes possible the intelligent han- 

 dling and presentation of the results. 



Some of the principal results were as follows: 

 The plant growth and absorption were greatest 

 in the solutions containing all three fertilizer ele- 

 ments, but not in equal proportions, the greatest 

 growth and greatest absorption being found in the 

 region below the center in the triangle. The di- 

 hydroxystearic acid had the effect of shifting 

 this region of greatest growth toward those ratios 

 higher in nitrogen. Although absorption was 

 greatest in this region, the ratios suffered the 

 least change; the greatest change is produced in 

 those ratios most removed from this normal re- 

 gion. 



The harmful soil compoimd inhibited growth 

 in all the solutions, but was the most harmful 

 in those ratios not well suited for plant growth 

 and least in those best suited for plant growth. 

 Moreover, it is less harmful in the presence of 

 those ratios mainly phosphatic or potassic and 

 this effect is also associated with a higher nitro- 

 gen removal. Tlie quantity of phosphate and 

 potash removed was less in the presence of this 

 compoimd. The investigations tend to throw 

 much light upon the relations between plant 

 growth, absorption, fertilizer action and infiuence 

 of organic compounds. 

 Concurrent Oxidizing and Reducing Power of 



Roots: Oswald Schreinee and M. X. Sullivan. 



The roots of growing plants, such as wheat, 

 have the power to oxidize alpha-naphthylamine, 

 benzidine, phenolphthalin, aloin, guaiac, pyrogal- 

 lol, etc. When indicators like alpha-naphthyla- 

 mine and benzidine are used, the colors due to 

 oxidation are most intense on the region of the 

 root where growth is most active, the most 

 marked oxidation showing by a distant band of 

 color just back of the root cap. Then comes a 

 practically colorless zone and then a colored zone, 

 the color becoming less intense toward the upper 

 part of the root. Wheat roots grown in sodium 

 selenite neutralized by hydrochloric acid reduce 

 the selenite with a pink deposit of selenium upon 

 the root. This deposit is most marked a short 

 distance back of the root cap just back of the 



