613 



occurrinj: in i)laiit food, Kmnerous trials liave shown that 20 <?rains of 

 8uperi)hospliate may be dissolved in 1,000 c. c. of water without difli- 

 culty. This is true, provided the superphosphate contains sufficient 

 free phosphoric acid, which is the case when 50° Baunie acid has been 

 used in its manufacture. Disuperphosphates (dicalcic phosphate) con- 

 tain some free phosphoric acid directly after their formation, but this 

 soon combines with the undecomposed tricalcic phosi)hate. The more 

 free phosphoric acid a superphosphate contains the less will it be 

 decomposed by the action of rains. The action of the phosphoric acid 

 set free by the decomposition of the salt depends upon the conditions in 

 the soil. The dicalcic phosphate formed in nearly all of the processes 

 is dissolved by water with the aid of organic and inorganic acids. The 

 author further states, although the data which lead to the conclusion 

 are not presented in the article, that in soils whi(!li do not contain any 

 considerable amounts of ferrous and ferric oxides the free phosphoric 

 acid changes to a form available to the roots and plays no unimportant 

 part in the nourishment of i)lants. 



The nutritive value of cellulose, W. Henneberg and F. Lehmann {Landic. 

 Versnchs-Stationen, 38,^. 337). — A paper read by Dr. Lehmann before 

 the section of the meeting of naturalists above referred to. In two series 

 of experiments, each of several months' duration, two sheep were fed 

 a basal ration consisting of bean meal, barley meal, pea-nut cake, and 

 oat straw. To this were added sugar (either cane sugar or glucose), and 

 crude fiber prepared from rye straw by the action of sodium hydroxide 

 solution, each in long periods and in such a way that each sugar period 

 and each cellulose period was preceded and followed by a period in 

 which the basal ration was led alone. 



The results of the two trials indicated that cellulose prepared as stated 

 above, was nearly or quite equal in value as an albuminoid conserver 

 to the easily soluble carbohydr.ites. The second exi)eriment, in which 

 the carbonic acid and marsh gas given off by the animals were deter, 

 mined by means of a Pettenkofer respiration apparatus, showed that 

 the amount of marsh gas given off by ruminants may be very high. 

 !N'early 10 per cent of the total carbon exhaled was in the form of this 

 gas. The x^roduction of earbonic acid and marsh gas was increased 

 when sugar was added to the basal ration, as well as when cellulose was 

 added. This indicates that the marsh gas exhaled does not come exclu- 

 sively from the digestion of the cellulose of the food, but probably from 

 that of other carbohydrates also. 



The author is led from these experiments to believe that cellulose 

 ilfects the production of fat as well as the albuminoid metabolism. 



Changeability of the fats of certain feeding stuffs, 0. Reitmair {Landic. 

 Vcrsuclis tSldtioneii 38, pp. ;573-100). — The object of the investigation here 

 reported was to get light upon the changes which occur in the fats of oil- 

 cake and kindred feeding stuffs. The importance of the subject is not 

 25909— ]No. 10 G 



