Seventeenth annual meeting. 89 



G-. Bonnier and L. Mangin. Comparative experiments respecting the oxygen ab- 

 sorbed and tbe carbon dioxide evolved in the dark by various species of plants, sbow that 

 the ratio between the two quantities is constant, whatever the temperature, but that the 

 ratio varies for different plants. Tbe activity of the action increases rapidly with the 

 temperature. (J. C. S., CCLXI—857.) 



Pit bard lias made some interesting researches in nitrification. He finds that certain 

 salts, if applied to tbe soil exercise an energetic nitrifying power. Tbe effect was es- 

 pecially marked with calcium sulphate. Taking that as 100, the nitrifying power of 

 sodium sulphate was 47.91; of potassium sulphate, 35.78; of calcium carbonate, 13.32; 

 and of magnesium carbonate, L2.52. This remarkable power of gypsum explains its 

 beneficial action when used as a fertilizer. Its application to soils poor in calcium com- 

 pounds cannot be too highly recommended. (J. V. S., CCLXII — '■>-■'(.) 



< >. Marek lias made analyses determining tbe distribution of the sugar in the beet. 

 He divided the beet into eight sections from top to bottom, and determined the sugar in 

 each. Tbe rotatory power was greatest in the second section, and decreased downward. 

 The upper section is between the fifth and sixth in amount of sugar. He also deter- 

 mined the lateral distribution of the sugar, and found the largest amount in a zone be- 

 tween one-seventh and two-sevenths of the distance from the outside to the center. 

 (J. C.S., CCLX— 766.) 



Messrs. Lawes and Gilbert have published a long memoir on the composition of the 

 ash of wheat straw and wheat grain, showing the influence of varying seasons and differ- 

 ent manures. The length of the paper forbids any attempt at abstraction. (J. C. S., 

 CCLXI—S05.) 



Tbe most striking feature in the progress of analytical chemistry, is the number of 

 methods which have been proposed for the detection or estimation of nitrogen in its, 

 various combinations. Accurate valuations of nitrogenous fertilizers are of growing im- 

 portance to agriculture, and the attention of agricultural chemists throughout the world 

 is directed toward this subject. At the instance of the German Manure Manufacturers' 

 Association, a general meeting of chemists was held at Wiesbaden, last May, under the 

 Presidency of Prof. Fresenius, to consider proposals for uniform methods for nitrogen 

 determinations. They agreed upon methods for the preparation of samples, and the de- 

 termination of ammoniacal, organic, and nitric nitrogen. (C. N., 50 — 180.) 



A new method of estimating organic nitrogen has been devised by J. Kjeldahl. Tbe 

 dried substance is digested for several hours with concentrated sulphuric acid, at near 

 the boiling point of the acid. The conversion of the nitrogen into ammonia is com- 

 pleted by adding potassium permanganate in very small quantities until an excess is in- 

 dicated by the solution becoming green. When cold tbe solution is made alkaline by a 

 strong solution of caustic soda and the ammonia is distilled into standard acid. The 

 author has obtained satisfactory results with a large variety of nitrogenous substances. 

 {J. C. S., COL VI— 364.) 



Prof. 8. W. Johnson finds that simply calcium hydrate may be substituted for soda- 

 lime in the conversion of organic nitrogen into ammonia for purposes of analysis. ( Am. 

 Chem. Journal, Vol. '<', p. 60.) 



G. Lunge. — (1) Lime, soda and magnesia in excess liberate all the ammonia in am- 

 monium chloride equally well. (2) Amines are liberated under the same circumstances 

 as ammonia, so that the assumption that magnesia avoids the decomposition of amines 

 which may be present in commercial manures is quite erroneous. (J. C. S. 3 CCLX 

 — 77';.) 



A. G. Green and S. Rideal have published a method of determining nitrous acid by 

 means of a one-tenth normal solution of pure aniline, which they maintain is more ac- 

 curate than the permanganate process, and can be used in the presence of oxidizable 

 substances. (C. N., 4'J — 173.) 



