§ 112. FAEM-YAKD MAXURE. 213 



CHAPTER VI. 



FERTILIZERS. 



I. 



PRODUCTS OF THE FARM-YARD. 



FARM-YARD MANURE. 



112. In the examination of farm-yard manure, the part 

 soluble in water, and that which is insoluble in this agent, 

 should each be examined by itself, for it is important to 

 know the relative proportion and composition of these two 

 portions. 



To procure a sample of the manure, take several small 

 portions from different parts of the pile, mix them all 

 carefully together, breaking up the lumps while working 

 the mass over, and preserve 3-4 kilos, for examination. 



a. Water. — Dry 1000 grms. of this in the drying- 

 chamber, powder the residue as much as possible, or cnt 

 it up with shears, weigh the whole, dry about 50 grms., 

 accurately weighed, at 100° C, and calculate the loss of 

 weight for the whole 1000 grms. Grind this diied sub- 

 stance to a powder in a steel mill. 



b. Organic matter. — Ignite 6-8 grms. of this powder 

 with the usual precautions, including the determination 

 of carbonic acid and coal (§ 91). 



c. Carbonic acid. — Determine this in 5 grms. of the 

 powder (§ 60). 



d. JVitrogen. — Determine this in 1 grm. of the powder. 

 The small amount of nitric acid in the manure will be al- 

 most completely converted into ammonia during the com- 

 bustion, in the presence of so large a proportion of car- 

 bonaceous organic matter. The nitrogen in the amnionic 



