130 TOBACCO LEAF. 



more quickly than vegetable matter, but this is now 

 doubted. Tankage should be applied broadcast in the 

 spring and harrowed in. Tankage and all animal 

 fertilizers give the best results when used with manure, 

 for the latter is rich in organic matter while meat is 

 deficient in it. 



Dried Blood. A better article than tankage, be- 

 cause of its more uniform analysis, is dried blood. There 

 are several grades of blood, since it is often mixed with 

 tankage, when it is called blood and meat, but in the 

 wholesale fertilizer trade, there are but two grades, the 

 soft red blood and black blood. Both of these products 

 arise from the coagulation of liquid blood by steam. 

 Under this heat the solid portion settles and the liquid 

 is drawn off. The residue is then dried. If too much 

 heat is used in drying, the blood solidifies into a solid 

 black mass, hard and brittle. This, when ground, 

 separates into small, black, glittering particles, having 

 a gritty feeling, and constitutes the black blood of com- 

 merce. A lesser application of heat prevents the melt- 

 ing of the blood, and it comes out as a red powder, soft 

 to the touch. It is difficult to dry this blood success- 

 fully, and dried meat or tankage is frequently added to 

 facilitate the drying, which makes the blood and meat 

 so generally sold, and which more properly should be 

 classed as tankage. 



Black and red blood differ materially in their action. 

 The latter has acquired quite an insoluble condition that 

 detracts from its agricultural value. It runs from 

 twelve and one-half to fourteen and one-half per cent of 

 nitrogen. Eed blood contains less, only about ten per 

 cent or eleven per cent of nitrogen, but it is a beautiful 

 nitrogen preparation and admirably suited for fertilizing 

 purposes, being soluble, while not too much so. It is, 

 undoubtedly, the best animal ammoniate. Unfor- 

 tunately, however, it rarely gets into farmers' hands, for 



