GUANO. 199 



night-soil. When magnesia is not present, it will 

 be necessary to add some magnesian limestone or 

 Epsom salts. The night-soil should be mixed thor- 

 oughly with the ashes, and exposed to the air to 

 dry. The disagreeable smell is thus quickly removed, 

 and a pulverulent manure obtained, which can be 

 applied to the fields with facility.'^ 



Animal charcoal, which has served for the discol- 

 oration of sugar, possesses the property of removing 

 the offensive smell of night-soil, and is of itself an 

 admirable manure. In cases where it can be pro- 

 cured with facility, it will be found to add to the 

 efficacy of the latter.f 



GUANO. 



The sterile soils of the South American coast are 

 manured with a substance called guano, consisting 

 of urate of ammonia and other ammoniacal salts, by 

 the use of which a luxuriant vegetation and the 

 richest crops are obtained. Guano has lately been 

 imported in considerable quantity into Liverpool and 

 several other English ports, and is now experi- 

 mentally employed as a manure by English agricul- 

 turists. A consideration of its composition and 

 mode of action cannot, therefore, fail to be accept- 

 able. 



Much speculation has arisen as to the true origin 

 of Guano, J but the most certain proof is now af- 

 forded, that it has been produced by the accumula- 



* Night soil deprived of its odor and rendered portable is termed 

 poudrette. One mode of preparing it, practised in France, is by boiling 

 the refuse matter of slaughter-houses, by steam, into a thick soup and 

 then mixing the whole into a stiff paste with sifted coal ashes, and 

 drying. It is almost one half animal matter. If putrefaction should 

 have begun, the addition of ashes, sweetens the whole, and the pre- 

 pared "animalized coal," as it is termed, is as sweet to the nose, as 

 garden mould. — Dana. 



t For an accoimt of Mr. Daniell's artificial manure, see Appendix. 



I Much of the information regarding Guano here given is extracted 

 from a paper in Liehig's Mnnalerif xxxvii. 3, 291. 



