“It is an unpleasant job,” said the Deacon, “but it pays well to empty the vaults at least twice a year.”
“If farmers,” said the Doctor, “would only throw into the vaults from time to time some dry earth or coal ashes, the contents of the vaults could be removed without any disagreeable smell.”
“That is so,” said I, “and even where a vault has been shamefully neglected, and is full of offensive matter, it can be cleaned out without difficulty and without smell. I have cleaned out a large vault in an hour. We were drawing manure from the yards with three teams and piling it in the field. We brought back a load of sand and threw half of it into the vault, and put the other half on one side, to be used as required. The sand and fæces were then, with a long-handled shovel, thrown into the wagon, and drawn to the pile of manure in the field, and thrown on to the pile, not more than two or three inches thick. The team brought back a load of sand, and so we continued until the work was done. Sand or dry earth is cheap, and we used all that was necessary to prevent the escape of any unpleasant gases, and to keep the material from adhering to the shovels or the wagon.”
“Human urine,” said the Doctor, “is richer in phosphoric acid, but much poorer in nitrogen and potash than the urine from horses, cows, sheep, and swine.”
“Some years ago,” said the Deacon, “Mr. H. E. Hooker, of Rochester, used to draw considerable quantities of urine from the city to his farm. It would pay better to draw out the urine from farm animals.”
“The figures given above,” said I, “showing the composition of human excrements, are from Prof. Wolff, and probably are generally correct. But, of course, the composition of the excrements would vary greatly, according to the food.”
It has been ascertained by Lawes and Gilbert that the amount of matter voided by an adult male in the course of a year is—fæces, 95 lbs.; urine, 1,049 lbs.; total liquid and solid excrements in the pure state, 1,144 lbs. These contain:
| Dry substance—fæces, 23¾ lbs.; urine, 34½; total, 58¼ lbs. Mineral matter—fæces, 2½ lbs.; urine, 12; total, 14½ lbs. Carbon—fæces, 10 lbs.; urine, 12; total 22 lbs. Nitrogen—fæces, 1.2 lbs.; urine, 10.8; total, 12 lbs. Phosphoric acid—fæces, 0.7 lbs.; urine, 1.93; total, 2.63 lbs. Potash—fæces, 0.24 lbs.; urine, 2.01; total, 2.25 lbs. |
The amount of potash is given by Prof. E. Wolff, not by Lawes and Gilbert.
The mixed solid and liquid excrements, in the condition they leave the body, contain about 95 per cent of water. It would require, therefore, 20 tons of fresh mixed excrements, to make one ton of dry nightsoil, or the entire amount voided by a mixed family of 43 persons in a year.