MANURE. 145 



mire, the farmer buys in every hundred pounds of 

 poudrette, 200 lbs. of the best human excrement, and 

 in form not only portable, but perfectly inoffensive. 

 The value of good poudrette, depending on its am- 

 monia, is, compared with cow dung as 14 to I. 



210. There is yet another form of poudrette, 

 which though much used in France, has not been 

 introduced here. It is almost one-half animal mat- 

 ter, and it is formed without any offensive evolution 

 of gas, by boiling the offal of the slaughter-house, 

 by steam, into a thick soup, and then mixing the 

 whole into a stiff paste, with sifted coal ashes, and 

 drying. If putrefaction should have begun, the ad- 

 dition of ashes, sweetens the whole, and the prepar- 

 ed " animalized coal," as it is termed, or poudrette, 

 is as sweet to the nose, as garden mould. It is 

 transported in barrels from Paris to the interior, and 

 is a capital manure. 



211. Guano is the excrement of birds. It is 

 found on our own northern rocks and islands, but its 

 great deposite is on the islands of the southern ocean. 

 It there forms immense beds, from 60 to 80 feet 

 thick. It seems to be a great geological formation, 

 and it is hardly possible, that it can be the accu- 

 mulated deposite of the excrements of birds. Hum- 

 boldt, who visited this region, and watched the pro- 



13 



