64 HORTICULTURE LECT. iv 



petrified manure, of which there are large beds in the 

 eastern counties. It is fairly active, yet sustaining. 



Thomas's phosphate powder, or basic slag, is pro- 

 duced in the conversion of cast iron into steel by 

 what is known as the Bessemer or "basic pro- 

 cess." It is composed of 15 to 25 per cent, of phos- 

 phoric acid and about 45 per cent, of lime. It is not 

 very quick in action but lasting in effect, and may 

 be of good service in fruit culture. 



It was at one time confidently asserted that 

 chemical manures were of very little value for light 

 soils, but that idea is exploded along with many 

 others which had no foundation in fact. 



In a moist whitish sand, described as chemically 

 barren, by the use of chemical manures alone, a crop 

 of 29 tons 17 cwts of swedes was obtained, and in 

 the following year there was a crop of turnips weigh- 

 ing 30 tons 7 cwts. per acre ; while peas were remark- 

 able for their productiveness. 



The practical deduction from these noteworthy 

 results is that the quality of soil depends upon its 

 mechanical state friability as well as upon its 

 chemical composition. 



Liming 1 Soils. A friable state of the soil, or 

 suitable consistency, is always desirable, and it is to 

 promote that, as well as to incite wholesome chemical 

 action, that we apply lime to heavy dense clayey 

 soil. This is done profitably at intervals of about 

 five years, and the average quantity used is about 65 

 bushels per acre, or nearly half a bushel to a rod. 

 The lime should be brought to the land in lumps fresh 

 from the kiln, placed in small heaps covered with a 

 few inches of soil, then, when slaked, spread on the 

 land and at once worked in, though not deeply. This 

 may be done early in spring, a few weeks before 

 sowing or planting. 



