Our supposable case is the second most difficult to take care of. The worst would be ledge. We have to contend with, however, hard, wet, impervious clay.
The best way undoubtedly is to underdrain the land, and then to distribute the sewage on the principle of intermittent downward filtration. This is rather expensive, and a customer is rarely willing to pay the bills for the same. I should always advise it as the best; but where not allowed to do so, I have had fair success with shallow French drains connecting with the tank or cesspool.
Siphon tanks, such as are advised by many sanitarians, that were used first in this country, I believe, by Mr. Waring, I have not been very successful with. Obstructions get into the siphon and stop it up, or it gets choked with grease. I prefer a tight tank, provided with a tell-tale, and that is to be opened either by a valve operated by hand, or that is arranged with a standing overflow like a bath tub, and that can be raised and secured by a hook.
Read before the Boston Society of Civil Engineers, April 1884 Journal A. of E. Societies.