CHEMICAL SCIENCE. 281 



so much of the subsoil as the atmosphere will readily decompose in 

 the year four, five, or six inches, descending gradually to two spits. 

 He employs six men at 2s. a day, and they dig an acre in five days, 

 making an outlay of 60s. for the whole ; but as only one half is to be 

 dug for the year's crop, the time and cost are reduced by one-half, 

 and thus brought down to the cheapest rate of ploughing. The cost 

 per acre, in the instance above mentioned, was 3 14s., the return 

 from the four quarters and two bushels of wheat, and the straw, 

 ll 14s., leaving a profit of 8. It should be understood thit the 

 cost includes rates, taxes, interest, scarifying, reaping in short, all 

 the operations from digging to harvest. 



The parish in which Mr. Smith resides contains 200 wheat-growing 

 acres; he calculates that fifty laborers would have dug these in two 

 months and eight days, so that, beginning the last week in September, 

 all would be "finished by the first week in December, leaving five 

 months for the occurrence of casualties and their reparation before 

 the crop has grown. His system, after the first ploughing, it will be 

 seen, is based entirely on spade-husbandry; he is of opinion, that it is 

 applicable to thousands of acres " of hitherto impracticable and unre- 

 munerating clay." 



Schleiden and Smith agree in their faith in nature's unassisted fer- 

 tilising powers, if not in their mode of clearing the way for the exer- 

 cise of those powers. The system of the latter combines fallow 

 without loss, for the yield is double ; nature is left to drop the ammo- 

 nia, and the time is given for its combination with mineral matters in. 

 the soil. The atmosphere contains all the organic elements of wheat, 

 and if the ground be kept stirred, uncrusted, and loosened to a suita- 

 ble depth, they will find their way in ; and nitrogen even, as late ex- 

 periments demonstrate, will be absorbed. As for inorganic constituents, 

 Mr. Smith believes that they always exist in sufficient abundance, if 

 sought for by frequent digging. 



USE OF NITRATE OF SODA AS A FERTILIZER. 



The Royal (English) Agricultural Society having offered a prize 

 for a manure equal to guano at a cost of 51. a ton, Mr. Pusey has shown 

 that the conditions are satisfied by nitrate of soda, and at a charge less 

 than that specified. He savs, in illustration, that forty-six acres of 

 land, if cropped with barle} . and dressed with seventeen hundred 

 weights of nitrate, would yiel J. an increase of eighty sacks beyond the 

 Quantity usually obtained. A carsro of this fertilizer was brought to 



* * < 



England in 1820, but for want of a purchaser, was thrown overboard ; 

 a second importation took place in 1830 ; and from that date up to 

 1850, the quantity brought from Peru, where the supply is inexhaust- 

 ible, was 239,800" tons; value, 5.000,000/. With the price reduced to 

 81. a ton, Mr. Pusey observes, "our farmers might obtain from their 

 own farms the whole foreign supply of wheat, without labor, and with 

 but a few months' outlay of capital. I do not mean to say, that no 

 failures will yet occur before we obtain a complete mastery over this 



