The chemical composition of stable manure does not, alone, suffice to explain its remarkable efficacy and the difficulty of replacing it by any other material. The composition of manure of course differs not only with different animals but also with the different feeds consumed by them; but the average composition of farmyard manure is approximately given thus by Wolff and others: ANALYSES OF VARIOUS FARMYARD MANURES. ========================================================== | 1. | 2. | 3. | 4. | 5. | | | | | Water | 71.00 | 75.00 | 79.00 | 79.95 | 72.33 Dry Matter | 29.00 | 25.00 | 21.00 | 20.05 | 27.67 Ash ingredients | 4.40 | 5.80 | 6.50 | | 5.87 Potash | 0.52 | 0.63 | 0.50 | 0.84[23]| 0.69 Lime | 0.57 | 0.70 | 0.88 | | 0.85 Magnesia | 0.14 | 0.18 | 0.18 | | 0.14 Phosphoric acid | 0.21 | 0.26 | 0.30 | 0.40 | 0.30 Ammonia | | | | | 0.02 Total Nitrogen | 0.45 | 0.50 | 0.58 | 0.78 | 0.46 ----------------+-------+-------+-------+----------+------- 1. Average composition of fresh farm manure (Wolff). 2. Average composition of moderately rotted farm manure (Wolff). 3. Average composition of very thoroughly rotted farm manure (Wolff). 4. Mixed cow and horse manure from a bed two feet thick, accumulated during the winter in a large covered yard, and packed solid by the tramping of cattle (The analysis by F. E. Furry). 5. “Box Manure,” consisting of mixed manure of bullocks, horses, and pigs (Way, Royal Agric. Soc. Journ., 1850, II., 769). [23] And soda. It is thus seen that the percentage of the important plant-foods in stable manure are minute when compared with those commonly found in “commercial” fertilizers. Nor are they so much more available for plant absorption than the latter; a very large proportion is not utilized at all the first year, and unless the amount applied is very large it hardly carries the supply needed for the usual crops.