Table i shows the composition of the material just as it was col- 

 lected and taken to the laboratory. Table 2 shows the composition of 

 the different samples of hen manure all reckoned upon the same 

 basis of dry matter in 100 pounds. 



Samples B-i, 2 and 3 are richer than the others in nitrogen, be- 

 cause the fowls received more animal food. Potash varies relatively 

 little. Phosphoric acid varies widely and must be greatly affected by 

 the amount of bone in the animal food given to the fowls. 



The comparison between the amounts of nitrogen shown in Table 

 2 in samples B-i, 2 and 3 and between samples G-i and 2 is par- 

 ticularly instructive. // illustrates the fact that hen manure unmixed 

 with absorbents or chemicals suffers very rapid loss of nitrogen. Sample 

 B-2 differs from B-i only in the fact that the interval between the 

 removal of droppings from beneath the roosts was longer. The sea- 

 son of this experiment was March, and the droppings were frozen a 

 part of the time. During warmer weather the loss must have been 

 yet greater. G-2 though accumulating only during three nights 

 seems to have lost relatively more nitrogen than B-2, perhaps because 

 the house was much warmer than the one from which samples B came ; 

 although this seems an insufficient explanation for the difference. 



Examination of Table i, especially comparison of the samples B-i 

 and B-2 shows that the fact that nitrogen has been lost is obscured 

 by the further fact that there has been an even larger loss of water. 

 The percentage of nitrogen in B-2 (Table i) is larger than in B-i, 

 but only because the former is dryer. Table 2 shows that there has 

 been a large actual loss. 



The free use of fine dry loam, or the admixture 

 Methods of of such materials as kainit, acid phosphate, 



Preservation. muriate of potash or land plaster, or of a com- 

 bination of some of these will effectively pre- 

 vent loss of nitrogen. Loam alone must be used in quantities so 

 large as considerably to increase cost of handling. Either kainit, 

 muriate of potash or acid phosphate alone is effective, but the mix- 

 ture especially with the first holds the material too moist for conven- 

 ient handling. Plaster is of little value as an absorbent of ammonia 

 and if largely used the mixture may form hard, dry cakes. 



