308 DIETKTTC DEFICIENCY. 



rice that they eventually die of slow starvation without showiiify 

 anv si_c^ns of jiolyneuritis. while if they are g^iven large su])jilies 

 of jjolished rice they develo}) polyneuritis within a few weeks. 



Some investigators have advanced the view that the vita- 

 mine requirements of an animal are specifically related to its car- 

 bohydrate metabolism. In the last resort this may be so, since 

 we have no way of completely excluding the carbohydrate meta- 

 bolism taking ])lace within the cells of the body. But since we 

 have observed polyneuritis in pigeons on a diet free from carbo- 

 hydrate, we ourselves are satisfied that there is no specific rela- 

 tionship between vitamine requirements and the cxo(/ciioits carbo- 

 hydrate metabolism, and that the gross energy intake is the im- 

 portant factor upon which the (juantitative demand for vitamine 

 depends. 



In concluding this very scrappy essay ui)on some of the })rob- 

 lems of nutrition, we need not be so obvious as to mention that 

 the field for future research on animal dietetics i> still a wide 

 one. We may, however, perhaps be permitted to hope that South 

 Africa will contribute as mucii to the store of human knowledge 

 in this direction as she has already done in others. 



Rubber from Alcohol.— 1. i. ( )stronu'sk'nskij de- 

 scribes in the Pelrograd .iffricitlttiral Gacclic a process i)atented 

 by him for the preparation of rubber from alcohol. The ])rocess 

 comprises two stages. Air is first pum])cd through the alcohol, 

 and the mixed vapours are passed through copjx'r tul)es cf)ntain- 

 ing spirals of red copi)er and silver gauze. The latter are at first 

 heated, but during the subsequent process remain incandescetit. 

 Acetic aldehyde and paraldehyde are thus formed. These are now 

 mixed with more alcohol and passed over strongly heated aliuni- 

 nium oxide, producing erythrene. which is collected in an auto- 

 clave wherein a small quantity of a catalyst has been placed. Raw 

 erythrene rubber, a pure chemical compound of fornuila 

 (C.iH,;)n, is thvts obtained, identical with chemically pure natural 

 rubber, but oxidising more rapidly, so that it is necessary to 

 protect it from atmospheric action and fit it for use in other 

 respects by adding about 15 per cent, of admixtures. These are 

 tannins to resist oxidation, amines, mixed with lead oxide to 

 aid in vulcanisation, and rul)ber resins, to increase elasticity. 

 This method of syntlietic rubber production has been subjected 

 to qualitative and quantitative tests by the Russian (lovernment. 



New PhOSPHATIC Ores, — According to the Chemi- 

 cal Ncii's"^'', M. de Rolliere, of Paris, announces the discovery of 

 a new ore of high phosphorus content in the granites of France. 

 It is a manganese jihosphate, extracted from a blackish brown 

 rock in cleavable masses, and has the following composition : — 

 Phos])horic acid. 33 i>er cent.; lime. 2.5 per cent.; manganese 

 oxide, 32.5 jjer cent.; ferric oxide, 32 per cent. 



* (iqt6) 113. 83. 



