254 THE WORLD'S LUMBER ROOM. 



so that one year of English weather would be enough to 

 wash away many of the deposits entirely ; and on the west 

 coast of South America there is owing to rain no guano 

 worth mentioning, except between latitude 13 N. and 

 21 S., while the locality in which it is most plentiful and 

 most valuable is the rainless region of South Peru. 



It is only recently that Europeans have learnt the value 

 of guano, but under the Incas the birds were strictly pre- 

 served ; landing on the islands during the breeding season 

 was forbidden on pain of death, and overseers were ap- 

 pointed to give their proper share of the valuable commo- 

 dity to each claimant at the right time. 



In the Cincha Islands, off Peru, the beds are two hun- 

 dred feet thick, and the supply is almost inexhaustible. In 

 addition to the droppings of countless sea-birds which have 

 resorted to these spots for centuries past, the guano is also 

 partly composed of the skeletons and eggs of birds, and the 

 bodies and bones of fishes and seals. It has undergone 

 much alteration by internal chemical changes, and emits a 

 strong smell of ammonia ; and since it consists chiefly of 

 phosphate of lime with soda, magnesia, and sulphur, it is a 

 powerful fertiliser, and enables even the sandy desert around 

 Lima to bear crops of maize. 



Osite or Sombrero guano is brought from a small island 

 in the West Indies, which is entirely composed of the bones 

 of turtles and other marine animals, together with coral 

 sand, &c., which have been cemented into a compact mass 

 by the droppings of birds. 



A magnificent crimson, called murexide, has been obtained 

 from guano, while a fine purple has been found in the copros 



