• PoLYTEanmo Association Proceedings. '*903 



. which is more easily kept free from slag. Ttpo or three tubular 



, rabbles are fitted to, eax;h furnace, to be used alternately, in order 

 to prevent over-heating. Each one is connected to the air-receiver 

 by long flexible tubes of India rubber. The air is turned on before 

 the rabble is introduced, and remains on until it is withdrawn, iu 



.order to prevent the narrow aperture from being choked by cinders. 

 By means of the blast rabble, the time occupied in bringing the 



,.iiolten iron to a " boil," has been reduced from thirty or forty 



. minutes to ten. A^ the .beginning of the operation, the sparks 

 thrown ofi", indicate that silica is being separated from the mass,- 



. and as soon as the. flame is clear, the tubular rabble is withdrawn 

 and the common rabble is substituted. A number of .experiments 

 have de.monstra,ted that the whole process from the time an ord^ 



_ nary furnace is fi.rst charged until the mass is finished, does not 

 consume more than one hour, and a quarter. The quality of the 

 material produced is said to be superior, and in no case thus far 

 has there. been any failure to produce the desired results. 



ACTION OF ALUMDfA AND OXYD OF lEON IN SOILS. 



At a late meeting of the London Chemical Society, Mr. E. War- 

 ■riiigton, jr., gav.e an account of experiments made by him, to deter- 

 ,mine the .part taken l)y oxyd of iron and alumina m the absorptive, 

 action of soils. He used; artificially prepared hydrates of alumina 

 and sesqui-oxyd of iron, also two samples of native soil containing 

 6.82 and 19.31 per centj respectively, of oxyd of iron {feiremit) 

 and alumina {alemit). Through these he passed solutions of bone 

 phosphate of lime, alkaline carbonates and sulphates, ammonia 

 salts, &c., for the purpose of ascertaining the rate and extent of 

 absorption. The soil used was first digested in weak acetic acid to 

 remove all calcareous constituents, which would have interfered 

 ,with the intended action, and then thoroughly washed with water, 

 .after which, it was placed in contact with the lime phosphate, a 

 current of carbonic acid being occasionally passed through it. At 

 the expu-ation of a week, the soil was found to have withdrawn 

 ,93.8 per cent of the phosphoric acid, and only forty-nine per cent 

 of the lime originally present in the solution, from which the 

 author infers that alumina and peroxyd of iron possess a special 

 affinity for this acid, and that all the phosphoric applied to land in the 

 shape of manure, must ultimately become converted into phosphates 

 of iron and alumina; and, if the proportion of iron be sufficiently 

 large, all the acid will be retained by preference in the form of 



