MANURE. 177 



of organic matter, guano can be no proof that plants require 

 not geine, containing as it does, by analysis, 12 per cent, of 

 soluble organic matter. 



But this soluble matter will avail nothing without moist- 

 ure ; hence, in Peru, from the days of the Incas, till now, it 

 is the practice, according to Dr. Von Tschudi, ( Travels in 

 Peru,) a few weeks after the seeds begin to shoot, to dig a 

 little hollow round each plant, which is filled up with guano, 

 and covered with earth. After 12 or 15 hours, the whole 

 field is laid under water for some hours. In a few days the 

 growth of the plant is doubled. 



Guano is applied in best proportion in England and in 

 this country, at the rate of about 3 to 4 cwt. per acre. It is 

 still better applied mixed with one-half yard-manure. It 

 should be applied annually in small doses ; 3 to 4 cwt. are 

 considered equal to 20 or 25 tons of manure. 



213. The dung of all domestic fowls, and of birds in gen- 

 ral, contains salts similar to those in guano ; and while this 

 subject is under consideration, the fact may be mentioned, 

 that it has experimentally been proved, that the dung of 

 pigeons is f ths stronger than horse manure. And for stoved 

 mulberries, vines, peaches, and other plants, the droppings 

 of the barn-yard fowls, 1 part to from 4 to 10 of water have 

 been found to produce excellent results ; the trees having, at 

 the end of two years, the most healthy and luxuriant ap- 

 pearance imaginable. The poultry yard is, to a careful 

 farmer, a rich source of vegetable food. How much a 

 single hen can contribute to increase the crops, may be seen 

 from the following account, from Vauquelin. 



214. In ten days a hen ate 74'J4 grains of oats, which con- 

 tained of 



Phosphate of lime, .... 91.8348 grains. 



Silica, 141.8G16 '* 



8* 



