102 ELEME^AilY AGRICULTUKAL CHEMISTRY 



;In the nitrogei'.on^ yarieties the nitrogen is largely present 

 as ammonium salts, and some of the phosphoric acid as soluble 

 alkaline phosphates. 



Bats' guaoio, consisting of the dried excrement of bats, 

 occurring in caves in some countries, is of variable composition, 

 being often mixed with fine silt. It always contains a con- 

 siderable amount of nitrates^ 



2. Poultry and pigeon dung are rich manures, but seldom 

 abundant enough to have much importance in ordinary 

 farming. 



3. Seaweed is a valuable manure, undergoing rapid decom- 

 position in the soil. In the fresh state it contains about 

 80 per cent, of water, from 0*3 to 0'7 per cent, of nitrogen, 

 from 0-3 to 2 per cent, potash, and from 0*1 to 0*4 per cent.'' 

 of phosphorus pentoxide. 



4. Fish Manure or Fish Guano. — This usually consists of 

 the dried refuse — heads, bones, and other offal — of fish, and is 

 a rich manure, containing about 9 per cent, of nitrogen and 

 10 per cent, of phosphorus pentoxide. The presence of much 

 oil in this manure is objectionable, because it repels water and 

 hinders decay in the soil, and in some cases it is extracted by 

 means of volatile solvents. 



5. Dried blood from slaughter-houses is a valuable manure, 

 easily decomposing in the soil. It contains 10 or 11 per cent. 

 of nitrogen, and nearly 2 per cent, of phosphorus pentoxide 

 Meat meal is similar in composition, but contains more phos 

 phates. 



6. Shoddy manure or woollen waste is essentially the wool 

 fibres which have become so short by repeated spinning, 

 weaving, &c., that they will no longer hold together. Mixed 

 with the wool residue, however, is a variable quantity of cotton, 

 grease and dirt. The usual product contains about 7 or 8 per 

 cent, of nitrogen, and is remarkable for the slowness with 

 which it decomposes in the soil. It is essentially a nitrogenous 

 manure, but contains small quantities of potash (perhaps 

 0-5 per cent.) and phosphorus pentoxide (about 0-3 per cent.). 



