MANURE. 137 



nitrogen as carbonate of ammonia of the shops, will form 

 about 3 per cent, of the weight of the dung ; or a bushel of 

 86 lbs. will contain, in round numbers, 2^ lbs. of salts of 

 ammonia, potash, soda and lime. 



189. The cow, then, is the great manufacturer of salts and 

 geine, and it is a question of the highest interest. What is the 

 daily produce of her manufactory ? In order to determine 

 this, the following experiment was conducted with great 

 care, at the barn cqjinected with the print-works of the Mer- 

 rimack manufacturing company, in Lowell. A single cow, 

 being only an average producer of the article in question, 

 was selected from the 50 cows usually kept at the establish- 

 ment. She was fed as usual, and as the other cows were. 

 The food and water were accurately weighed for seven days. 

 She consumed, in this period. 



Water, 612 lbs. 



Potatoes, 87 " 



Hay, 167 " 



Total, 866 " food and drink, and 

 voided, free from her liquid evacuations, 599 lbs. of dung. 



From the facts which have been now stated, it is evident 

 that one cow prepares, daily, from 24 lbs. of hay, and 12^ 

 lbs. of potatoes, about one bushel, or 85.57, lbs. of dung. 

 This affords only 14.04 lbs. of solid manure, composed of 

 salts and of hay, so acted on by the digestive organs, as to 

 form geine, when united with ammonia, produced by putre- 

 faction. 



One cow daily forms, therefore, about 

 13 lbs. geine. 



i " say 3 oz. of bone-dust, or phosphate of lime, 

 •j^ " say IJ oz. of plaster of Paris, or sulphate of lime. 

 j\ " say IJ oz. of chalk, or carbonate of lime. 



