Organic Manures 



But when it is obtainable in large quantities it 

 is preferable to convert it into 



Dried Blood. 



There are two methods of making dry blood, but 

 the richness of the product obtained does not vary 

 much. First the blood may be allowed to coagulate 

 and the fibrine which can be put to another use is 

 separated. Then the clotted blood is dried, when it 

 contains about lo per cent, nitrogen, a little phos- 

 phoric acid [P2O5], and a little potash [KgO]. After- 

 wards it is pulverised and applied directly to the 

 ground, or employed in the manufacture of com- 

 posite manures. 



By the second method the fibrine is removed 

 before the formation of the blood clots and treated 

 separately, but it is added later to the defibrinated 

 blood before desiccation. 



The dried blood is in the form of black or brownish 

 grains of bright fracture. It can also be pulverised, 

 in which state it is perhaps a little easier to spread ; 

 this form is, however, less advisable, because it 

 easily absorbs the moisture of the atmosphere. 

 This absorption increasing its weight, but diminish- 

 ing the percentage of nitrogen, does not, however, 

 represent a real loss, because being bought by the 

 sack the extra weight is immaterial, while the pro- 

 duce is bagged sufficiently soon after the manufac- 

 ture of the manure to avoid waste ; but it has been 

 observed that, after having absorbed moisture, the 

 dried blood throws off its ammonia, and this means 

 considerable loss. Also pulverised dried blood may 

 be easily adulterated, nitrogenous organic matter, 



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