FERTILIZERS. 65 



Ground Limestone and Shells are sometimes applied as a fertilizer, and are similar 

 in effect to old air-slacked lime, or shell-marl, being a carbonate of lime in their principal 

 composition. 



Its action is more speedy when ground fine than when coarsely ground. It is useful on 

 such soils as are benefited by the application of lime. Ground shells are also sometimes used 

 as a fertilizer. They contain carbonate and phosphate of lime, and often some animal mat 

 ter. It is better to burn them first, as they are then converted into nearly pure lime; besides, 

 this is the easier and cheaper method of preparing shells for use. 



Gas Lime. Lime from gas-works is said, by competent writers, to be for agricultural 

 purposes about equal in value to common lime. 



It is the refuse lime that has been used in the manufacturing of gas, and consists mainly 

 of carbonate of lime, some sulphur, tar, and sulphate of lime, and must be applied more 

 cautiously or in more moderate quantities than common lime. It is safer to apply it after a 

 few weeks exposure to the air, as it would be liable to poison vegetation if used fresh from 

 the gas works, It is very important that it be well pulverized, that it may be evenly spread 

 upon the land It may be applied to grass or plowed lands for wheat or other crops, and 

 should in the latter case be well harrowed in. Some farmers pile it in small heaps in the fall 

 or winter, and spread it in the spring. When designed for plowed crops, it would be well 

 to spread it upon the soil late in the fall or winter, that it may be exposed to the air before 

 being harrowed in. It is also valuable for the compost heap. 



Its acrid qualities are said to render it valuable as an insect-repeller, and, when strewn 

 sparingly over young turnip-plants, to repel the turnip-fly. Some writers recommend its use 

 at the rate of 25 bushels per acre, but we think it would be well to experiment cautiously 

 with a smaller quantity at first. 



Bones contain a large proportion of phosphate of lime and other substances which ren 

 der them valuable for fertilizing purposes. There is, in fact, no ingredient of the bone that 

 is not useful to vegetation, and it is well adapted to almost all soils and nearly all agricul 

 tural products, especially so to the various kinds of grains, to potatoes, turnips, clovers, and 

 most garden vegetables. Since bones decompose so slowly, one of their chief factors of value 

 in agriculture is the fineness to which they are reduced before applying, since the finer they 

 are ground the more readily will the plants be able to appropriate them as plant-food. 



Bone is especially valuable for fruit-trees. Many farmers use bones to place under the 

 roots of grape-vines and fruit-trees when setting them, putting a peck or more of old bones 

 in the bottom of the place dug for inserting the roots. This will give something for the 

 rootlets to feed upon for years, as they become slowly decomposed, and will be of great vahie 

 in promoting the future growth and vigor of the trees or grape-vines. As bone-dust is rather 

 slow in decomposing, it is recommended by many writers on agriculture to apply it in 

 autumn or early winter, thus giving the rains and melting snows an opportunity to act upon 

 it, and wash it among the roots of plants. It may be sown broadcast at the rate of from five 

 hundred pounds to a half ton or more per acre, according to the nature and needs of the 

 soil. In England, the enormous quantity of a ton and a half of bone manure per acre is often 

 applied to pastures of old clay soil in keeping them productive; and English writers on the 

 subject state that there is nothing equal to it, either in the permanency of its effects, or in the 

 production of a sweet, luxurious herbage, of which the cattle are fond. 



Pulverizing and Reducing Bones. There are various methods of pulverizing or 

 reducing bones for agricultural purposes. Grinding is the best process when a mill is acces 

 sible for that purpose, and the finer they are ground the better. When grinding is impos 

 sible, for lack of a suitable mill, many farmers reduce them by the use of ashes and liquid 

 manure, by first breaking the bones, as well as may be, with a sledge-hammer, and then 



