230 EEPOET OF COMMISSIONER OF FISH AND FISHERIES, 



TABLE B. 



Eind of fertilizer. 





Dry ground flsh-scrap 



Dry ground tishscrap 



Dry ground lisli-«crap, old, 187G . 

 Dry ground lish-scrajj, new, 1877 



Dry ground fish-scrap 



Dry ground flsh-scrap 



Dry ground fish-scrap 



Dry ground fish-fcrap 



Dry ground fisli-scrap 



Dry ground fi.^h-scrap 



Drj' ground flsh-scrap 



Dry ground fish-scrap 



Average 



Pish by Adam son's process 



Fish by Adamson's process 



Fish by Goodalo's process 



Per ct. 

 10.75 



IC. 59 

 23.95 



19.57 

 9.03 



11.38 



10.74 

 9.76 



11.19 



Per ct. 



8.52 

 8.21 

 7.35 

 7.30 

 9.26 

 8.77 

 7.98 

 8.04 

 8.51 

 8.43 

 7.77 

 8.78 



8.61 



9.88 



13.66 



8.24 



4.91 



3.67 



11.45 



10.78 

 10.74 

 10.24 



11.32 

 11.15 

 11.56 



8.94 

 7.30 



^V aste from faulty mamfacture and use of Jish fertilizers. 



300. Au enormous loss results to our agriculture from the waste of fish 

 that might be saved, from faulty manufacture of fish into fertilizers, 

 from wrong use of the fertilizers when made, and from the exportation 

 of the best products to Europe, where their value is better understood. 

 This loss will be prevented in proportion as the nature and uses of fish 

 manures are learned. 



51. The use of fish fertilizers in agriculture. 



Chemistry of plant nutrition. 



301. Not only farmers and merchants, but many manufacturers as 

 well, have a very poor understanding of what constitutes the value of 

 fish as fertilizers, and how they may be most economically utilized. It 

 will be well, therefore, to consider briefly some of the principles that 

 decide the value and usefulness of fertilizers in general, and of fish 

 l^roducts in particular. 



Fish manures, like other commercial fertilizers, are valuable because 

 they supply plant-food which crops need and soils fail to furnish. Their 

 main value depends upon their content of nitrogen and phosphoric 

 acid. These are the most valuable and costly ingredients of commercial 

 fertilizers. 



Plants, like animals, require food for life and growth. A part of the 

 food of plants is supplied from the atmosphere, the remainder is de- 

 rived from the soil. No ordinary cultivated plant can thrive without a 

 sufScieut supply of each of a number of substances needed for its food. 

 With an abundance of all of these in forms in which the plant can use 

 them, and with other circumstances favorable, the plant will flourish 

 and the yield be large. But if the available supply of any one of them 



