mal falling below 97 per cent. of that in food. The following table* shows for itself:

It is seen that different species of farm animals do not make equally valuable manure from the same kind of food. Other things being equal, a growing animal makes poorer manure than one full grown, because of the demands made upon the food for the formation of bone and muscle. With the same feed a cow giving milk makes less valuable manure than one that does not, for the milk takes up quite an amount of nitrogen and mineral substances. The cattle withdrawing the least manurial value from the food they eat are fattening animals, and those standing still and making no growth or producing nothing.

We are quite safe in assuming that on the average 80 per cent. of the nitrogen and 95 per cent. of the phosphoric acid and potash that are fed to farm animals pass into the solid and liquid excrements. Taking these figures as a basis, and knowing the composition of any cattle food, we can easily calculate the relative money value of the manure it is capable of producing, provided one can settle upon a fair price per pound for the valuable ingredients. Now we have a list of prices from which commercial manures are valued, that is, it costs so much to obtain a pound of nitrogen according to the form in which it exists, and the same for phosphoric acid and potash. The nitrogen of fish can be bought for twenty cents per pound, and probably has about the same value as that of stable manure. The real value of the nitrogen in manure depends somewhat upon the digestibility of the food from which it came. All the nitrogen that is contained in the digested nitrogenous compounds and not used by the animal passes out in the urine, while the undigested nitrogen passes into the solid excrements. The nitrogenous compounds of the urine are much more easily decomposed and made over into plant food than those of the solid excrements, therefore are more valuable. While not over 50 per cent. of the nitrogenous substances contained in straw would be digested, as much as 85 per cent. of the same compounds in corn meal would pass through the process of digestion. A larger percentage of the nitrogen of the latter would therefore be found in the urine, consequently ten pounds of that element as existing in manure produced by corn would be more valuable than the same quantity in manure made from straw. In general, it can be said that the valuable constituents of the excrements from concentrated cattle foods have a higher

*Taken from Wolff's Praktische Dungerlehre.

More than 100 per cent, because of the mineral substances in the water drank, and that accidentally get into the food.

For yield of corn crop, 1882, Plate V, for 20, read 29.

Soluble

mentioned price of the nitrogen of fish as a basis for calculation. phosphoric acid is worth twelve and a half cents per pound. Only a portion of that even in well-rotted manure is soluble, so that nine cents may be assumed as a fair price for the phosphoric acid of stable manure. The alkalies are to quite an extent soluble, as they go out largely in the urine, and can probably be considered as worth four cents in the total excrement.

The money values given in the following table are calculated on the basis given above, viz: 80 per cent. of the nitrogen, and 95 per cent. of the phosphoric acid and potash of the food are considered as passing into the manure, these three ingredients being estimated as worth twenty, nine, and four cents per pound, respectively. From the values thus obtained 20 per cent. is deducted on account of greater bulk and larger dilution of farm compared with commercial manures. The greater bulk causes more expense in handling, and the dilution causes slower action, the returns from invested capital not being so immediate as is the case with concentrated fertilizers.

If a farmer can afford to buy commercial fertilizers he can safely make use of the above estimates in calculating the manure value of purchased cattle foods, even if the food stuffs are fed to milch cows or growing animals. When fed to fattening animals still higher values could rightfully be used. The table plainly indicates that when any material is bought to feed to cattle the purchaser desires profit from two sources. He gets an increased production of meat or milk, and also is able to raise larger crops because of the great amount of fertilizing material he is enabled to apply to his land. Is it not a fact that the cheapest way to buy fertilizers is to purchase them in the form of wheat bran, corn meal, or cotton-seed meal? The weight of fresh manure that would be produced by a ton of any food stuff can be approximately determined. About 50 per cent. of the solids of the food passes into the solid and liquid excrements. The mixed excrements contain about three fourths water. Taking one half of the solid matter in a ton of hay, which would be half of about 1,760 pounds, and multiplying that weight by four, we should have 3,520 pounds as the weight of manure from one ton of hay. To this must be added the litter, bringing the quantity up to about two tons. A cow wintered upon two tons and a half of hay would therefore produce not far from five tons of manure, provided she be well littered and none of the excrements be wasted.

If the hay be first class, according to the estimates of the previous table,

the above five tons of manure, made from two and a half tons of hay, would be worth about $14 65, no account being made of the value of the litter. What, over $14 00 worth of manure from one cow in one winter, when she eats nothing but good hay? Yes, at the present prices paid for fertillizers it would cost that sum to replace the nitrogen, phosphoric acid, and potash in that manure if it were sold from the farm.

It might possibly be of some interest to estimate the money value of a cord of stable manure, basing the calculations upon its chemical composition. Such manure varies so, however, in the amount of water it contains, and because of the food that may have produced it, that the value placed upon any given sample would apply only to manure produced under like conditions of food and treatment. The excrements of A's animals, that eat nothing but hay and straw, are much inferior to those from B's cattle that consume large quantities of corn meal, bran, and cotton seed. When one purchases stable manure, it is well to know what the animals that produce it have eaten. Partially rotted stable manure is worth more than fresh, because as it decomposes it tends to be more concentrated.

The Preservation of Farm Manures.

The latter must be eco

The

It is not enough to convert food into manure. nomically preserved, in order that the best results may be obtained. estimates made in the previous tables only hold where all of the solid and liquid excrements are saved. Successful farming demands that this be done. But is it generally done in Pennsylvania? Probably not.

How many manure heaps there are that lie exposed in a barn-yard, from which a stream of black water flows after every rain. Do you know, farmer, that the compounds of nitrogen, phosphoric acid, and potash that gives your manure heap the larger part of its value are, to quite an extent, soluble in water, and that they can easily be leached out, thereby causing you, indirectly, a loss of dollars and cents?

What more conclusive proof of the above statements do you want than the sight of the luxuriant grass growing in the track of the leachings from the barn-yard. If such leachings could all be taken up by your mowing fields it would be another matter; but very often this is not the case. Dr. Völcker, of England, carried on an investigation that led to a satisfactory demonstration of the effect of exposure and leaching upon a heap of yard manure. He exposed manure under four different conditions, and by weighing and analyses at stated periods was able to take account of the changes and loss that were taking place. The manure was submitted to the various conditions for nearly a year, which were as follows: No. 1. Fresh manure exposed in a heap against a wall. No. 2. Fresh manure kept under a shed.

No. 3. Fresh manure spread in open yard.

No. 4. Well-rotted manure exposed in a heap against a wall.

When the manure was first placed under the above-named conditions, it was weighed and analyzed, and during the year's time that it remained where it was placed, was weighed and analyzed four more times, in order to discover the changes that were going on. In the following tables are given the dates at which the weighings and analyses were made, the composition, and the percentage of loss by weight:

The manure was first exposed to the various conditions November 3, 1854.