128 NOBTH-CAEOLINA GEOLOGICAL SURVEY. 



Cotton seed is a well known substance, whose reputation as a 

 fertilizer is based in part upon its oil. But fish are rich in 

 oil, phosphoric acid and ammonia, and hence they form a con- 

 centrated manure. If the analysis is compared with those 

 which have been given in the foregoing pages, it will be seen 

 that the constituents offish are admirably adapted to the pur- 

 poses for which they have been employed. 



96. The same remark, however, applies equally well to 

 all animal matters flesh, bone, the hoofs, horns and hair, all 

 are active fertilizers, their speedy influence being dependent 

 upon the state and condition in which they are applied. Bone 

 ground finely is much more active than when it is coarse. 

 To obtain speedy action it must be soluble. But fish manure 

 occupies an intermediate position it is more speedy in its 

 action than bone dust, but it is more transient in its effects, 

 in which case, it has a close resemblance to guano. 



97. Crabs and fish of the same class have also been pre- 

 pared for a like purpose. The king crab resorts at seasons of 

 the year to parts of our coast in immense numbers. These 

 on being taken are dried and ground when it is prepared for 

 use. It has been sold under the name of Cancerine from 

 cancer, a crab. When compared with guano, it is found quite 

 similar in composition. As guano is supposed to owe its value 

 mainly to its ammonia and phosphate of lime, it may be com- 

 pared with fish or cancerine to determine their relative 

 values.* 



Thus Peruvian Guano contains of 



Ammonia, 15.00 



Phos. acid, 14.75 



Cancerine ammonia, 10.75 



Dry fish do 9.27 



Phosphoric acid, 7.78 



Phosphoric acid in cancerine, 4.05 



An immense amount of fertilizing matter is lost which might 

 be saved in the offals of fish. If they were dried or preserved 



* Geol. Survey of New Jersey, p. 61, for 1856. 



