106 THE CANADIAN NATURALIST. [^pril, 



tave been found and extensively worked on the islands of the 

 West African coast and elsewhere. Nor has commercial enterprise 

 confined itself to guano. Nitrate of sodium, formerly valued 

 chiefly as a substitute for saltpetre in the sulphuric-acid manufac- 

 ture, has of late years come more and more largely into use as a 

 powerful fertilizer ; and the vast deposits of this substance succes- 

 sively opene 1 up in several parts of the South American continent 

 are now extensively worked for the supply of the English manure- 

 market. As for bones and bone-ash, they have been imported by 

 thousands of shiploads, not merely from the boundless South 

 American pampas, — feeding-grounds and cemeteries of unnumbered 

 herds, from immemorial time, — but also from populous European 

 countries, whose soil could by no means spare them so well, and 

 whose fertility must have been seriously impaired by their with- 

 drawal. 



Good and Evil of the Trade in Manures. — The man- 

 ure-trade presents itself, therefore, in two aspects ; the one advan- 

 tageous, the other detrimental to mankind. Nothing can be more 

 advantageous than the collection and utilization of fertilizing 

 residua formerly cast away as worthless. The fossil phosphates 

 quarried out of the bosom of the earth, and the guano extracted 

 (by the successive intervention of seaweeds, fishes, and penguins) 

 from the depths of the ocean, are evidently so much treasure fairly 

 won from nature for the legitimate enrichment of mankind.* Even 

 the withdrawal of recent bones and bone-ash, from plains untenant- 

 ed as yet save by wild cattle, to fertilize the corn-fields of the 

 populous old world, must be accounted a legitimate commerce. 

 But the boundary line is over-passed, and the manure-trade becomes 

 abnormal, when bones are withdrawn from one populous country 

 to enrich the exhausted fields of another. 



Nor is the detriment thus occasioned confined to the country 

 whose soil is impoverished. In the closely knit relations of modern 

 commerce, the impoverishment of any one commercial country 

 reacts on the prosperity of all the others, by diminishing the stock 

 of exchangeable wealth in the world. If Germany, for instance, 

 grows less corn, her purchasing power for foreign goods, say 



* See, ia this connection, a paper by Mr. Sterry Hunt on Fisli-Manures 

 (Canadian Naturalist, vol. iv, pp. 13-23), where will be found much in- 

 formation on the theory of manures and on their commercial value. — 

 Editors. 



