AMERICAN INSTITUTE. 345 



of ammonia, and that the deterioration of farm yard manure is . 

 due, in a great measure, to the loss of this most fertilizing sub- 

 stance. Eut this " volatile carbonate of ammonia" which appears 

 In putrefying organic matter, is so inconsiderable in fresh as well 

 as in fermented dung, in all stages of decomposition, that it is not 

 worthy of notice in a practical point of view — so that the escape 

 of ammonia cannot be the cause of manure heaps losing much 

 fertilizing power, even by considerably long exposure to the at- 

 mosphere. But in the interior of a dung heap, where the heat is 

 often from 120 to 150 degrees of Fahrenheit, the ammonia is given 

 off so abundantly that its presence here becomes patent by its 

 characteristic pungent smell. Fortunately, the external cold 

 layers of dung heaps act as a chemical filter, and retain the am- 

 monia within so elfectually, that even a delicate red litmus papei: 

 is not altered in the least. As the faintest traces of ammonia 

 turn reddened litmus paper distinctly blue, it is plain that how- 

 ever strong the smell of a dung heap may be, it cannot be due to 

 the escape of ammonia. 



The London Farmers' Magazine, for Oct., 1857, says that the 

 above article, by Voelcker, is " the article" in the Journal of the 

 Royal Agricultural Society, last volume, and that farmers ought 

 to read it. 



BAD EFFECTS OF CLOVER HAY ON ANIMALS. 



Some late writers have taken the position that clever-hay pro- 

 duces a most injurious effect on domestic animals, particularly 

 horses; and that to this cause the great increase of diseased horses 

 is to be attributed. We lately heard a farmer affirm that he be- 

 lieved the introduction of clover- hay into general cultivation the 

 greatest curse yet inflicted on the country, and assigned as a rea- 

 son for this singular opinion, its effects on animals when used as 

 a fodder. Late English writers have attributed to this kind of 

 hay the prevalence of hove in horses ! and the great increase of 

 other diseases that affect the respiratory organs. 



This is a most important subject, and should receive a full in- 

 vestigation. Clover is too important a plant to be discarded or 



