MANURE. 203 



249. The urea being called equal to ammonia, it is seen 

 that the ammoniacal salts in human urine are very nearly 

 the same as those in cow-dung, but its effects in actual prac- 

 tice are found to be nearly double those in cow-dung. The 

 actual amount of salts in 100 parts of human, cow, and 

 horse-dung, is in round numbers, 1 per cent., while in the 

 liquids it averages 5.88, being in the cow 7.4, and in the 

 human 4 24 per cent., horse 6, according to Sprengel. 



250. All urine of course varies with the food of the ani- 

 mal, the season, and its age. White turnips give a weaker 

 liquor than Swedish. Green grass is still worse. Distillers' 

 grains are said to be better than either of these. The more 

 water the animal drinks, the poorer the urine. Doubtless 

 the liquids of fattening kine are richer in ammonia during 

 this period, for it contains a part of that nitrogen not carried 

 away in milk. In winter, urine contains much less urea than 

 in summer, sometimes only one-half Putrefaction changes 

 urea to ammonia. The time required for this varies. Urine 

 putrefying for a month, contains double the ammonia of 

 fresh urine. It <Ioes not wholly decompose in a month ; but 

 during all this time, gives off ammonia. Unless then mixed 

 with loam, or peat, or swamp muck, or where kept in tanks, 

 with thrice its bulk of water, or with oil of vitriol, 3 lbs. to 

 160 gallons of urine, or with plaster, copperas, or other sub- 

 stances which will form a fixed salt with ammonia, that will 

 escape. Urine is fully ripe, when it contains neither caustic 

 ammonia, nor urea. 



Food, exercise, age, condition, and sex of the animal, alter 

 the quality, and affect the quantity of the urine discharged, 

 it becomes therefore an interesting question. What is the 

 quantity and quality of urine which various animals discharge 

 daily and yearly ? 



On the average, a healthy 



