96 BOARD OF AGRICULTURE. 



fields under tillage crops, and the sales made are either of 

 grains or animal products, the soil will probably first show a 

 lack of phosphates, and the addition of bone-dust will increase 

 the yield of all the crops. Root crops, especially turnips, are 

 perhaps more sensitive to a failure of the phosphates than any 

 other crop. Potash fails also early, and the land is very grate- 

 ful for a supply. And so, one after another essential constitu- 

 ents of the ash of plants fail, and the productions of the farm 

 proportionately decrease. 



Farmers upon the old grazing farms of New England are 

 driven to the use of bone-dust, (or some form of phosphoric 

 acid, which we know is its potent principle,) and the decided 

 benefit almost uniformly experienced from its use in all soils 

 and all situations, fit for any kind of tillage, renders the fact 

 that it is valuable as manure universally admitted. 



A statement of Prof. Yoelcker, of London, a distinguished 

 agricultural chemist, that bones are the first manure which a 

 farmer usually buys, and which farming communities demand, 

 interested me. He states, in considerable detail, that wherever 

 agriculture is improved, throughout the world, the first lack of 

 the farmer is phosphates. The easiest source of supply is 

 bones, and not until that lack has been supplied in the soil does 

 he begin to search for ammoniacal manures. 



The fields which receive year after year, in rotation, the great 

 bulk of the manures of the farm, are often comparatively rich 

 in the phosphates and alkalies, while the out-lots and pastures 

 have been robbed for their benefit. 



This being the fact, we can easily account for the apparent 

 improvement of farms, when, in reality, they are losing value. 

 I find, wherever good farming prevails, that land not exhausted 

 comes up. It shows almost at once the good tillage ; responds 

 promptly. It shows an increase of manurial wealth in the soil, 

 even though the manures applied be altogether produced upon 

 the farm itself. And yet there is a draft somewhere. That 

 draft must be either upon the subsoil, upon the swamps, upon 

 the woods, or upon some part of the outlying portions of the 

 farm. 



It is natural that on such land pure phosphates would pro- 

 duce much less striking effects than upon those fields where a 

 real lack exists. Nevertheless, it is almost impossible to find 



