CHEMICAL SCIENCE. 263 



It appears, then, says Way, that it is quite incorrect to estimate the value 

 of the different kinds of woollen refuse by the known composition of the 

 wool itself; for, to whatever cause the inferiority may be due, it is plain that 

 they do not, on an average, contain two-thirds of the nitrogen found in the 

 raw material. 



The mineral substances found in wool refuse are of small fertilizing value. 

 In 100 parts of inferior wool refuse were found 



Water, 7-15 



Animal matter and oil, 58-52 



Phosphate of lime, 1-48 



Oxide of iron and alumina, 2 10 



Carbonate of lime, 9 42 



Sand, etc., , 21-23 



Loss, etc., '10 



This specimen contained about 2'5 per cent, of nitrogen. 



Professor Voelcker has explained the chief reasons for the considerable 

 difference of opinion, which exists in different places, with regard to the fer- 

 tilizing value of woollen substances (ibid., vol. xvi., p. 94). These, he consid- 

 ers, are to be best understood by a reference to their analysis, and the time 

 of their application, and the physical composition of the soil. Shoddy, for 

 instance, often contains from twenty to twenty-five per cent, of oil, which, 

 by excluding moistm*e, and the atmospheric air from the interior of the 

 wool hairs which compose this refuse, prevents its decomposition, as effectu- 

 ally as the oil in sardines, or a cover of grease the potted meat. And thus 

 the decomposition of the shoddy is retarded for a considerable period, so 

 that no effect is produced if it is applied to the land when the young \vheat 

 has already made its appearance, or even if applied two or three months 

 previously. But if the same refuse is applied to the land a considerable 

 period before the sowing of the crop which it is intended to benefit, or if it is 

 previously brought into a state in which it will readily ferment (and then it 

 may be applied at once to the young wheat), a very marked and early good 

 effect will bo produced by its use, since ammonia is then gradually formed 

 from the nitrogen of the shoddy. In light and porous soils, this necessary 

 prepai'ation proceeds much more rapidly than in stiff, heavy lands. 



The farmer, by his practice, confirms these chemical conclusions. The 

 Kentish hop-growers, we are told by Mr. S. Rutley, in his prize essay (ibid., 

 vol. ix., p. 562), deem woollen rags, shoddy, and refuse seal-skins, to be very 

 lasting manures, but. much more valuable and early in their effect on dry 

 than on wet soils. On the Kentish hop-grounds they apply from twelve to 

 twenty cwts. per acre of woollen rags, twenty to thirty cwts. of shoddy, and 

 about 100 bushels per acre of seal-skin. For corn-crops on light, chalky 

 land, or for grass, about ten or twelve cwts. per acre of woollen refuse were 

 used. -- Extracted from an article on icool, communicated by Cuthbert Johnson to 

 the (English) Farmer's Magazine. 



SURFACE MANURING. 



Agriculturists are very much exercised, at the present moment, whether 

 it is better to apply manures in a partially rotted state upon the surface of 

 the earth, weeks or months before they are required for crops, or to decom- 

 pose them in heaps, and plough them in as soon as applied, at planting? 



