THE PRESERVATION OF HEN MANURE. 

 Chas. D. Woods and J. M. Bartle:tt. 



The dung of fowls contains, in addition to the undigested resi- 

 due from the food, the excrements of the kidneys, and is there- 

 fore much more nitrogenous than that of other domestic animals. 

 Most of the nitrogen of the dung is in the form of uric acid and 

 is very readily available to growing plants. It is however very 

 quickly changed into carbonate of ammonia by putrefaction, and 

 as hen dung is ordinarily stored much of the nitrogenous matters 

 go off into the air as ammonia gas and is lost. The remarkable 

 fertilizing value of guano derived from the dung of sea birds 

 is due to the urates which it carries. Weight for weight, the 

 droppings of the hen roost are not nearly as valuable as guano, 

 but are of much greater value than ordinary barn manure. 



While there are quite a number of European and a few Ameri- 

 can analyses of hen manure, the writers failed to find other 

 studies upon hen dung and its use. Indeed the three pages 

 devoted by Storer* to the dung appear to sum up about all the 

 literature on the subject. 



COMPOSITION OF HEN MANURE. 



The table which follows contains all the trustworthy American 

 analyses of fresh hen manure that the writers have found. Other 

 analyses in which plaster in unknown amounts had been mixed 

 with the droppings, and of dried hen manure have been reported. 



The percentage of water in these samples was from 50 to 60 

 per cent. In all of them there had doubtless been a loss of 

 nitrogen in the drying of the samples before analysis. The loss 

 in the case of the samples analyzed at the New York Station was 

 estimated at 43 per cent. A sample of fresh dung from the 



* Agriculture, in some of its relations with chemistry, F. H. Storer, Chas. Scrib- 

 ner's Sons, New York, 1899, Vol. 1, p. 612. 



