Albert F. Noyes, West Newton, Mass., writes:

"In answer to the questions asked by Mr. T. M. Clark in a communication headed " Traps on House Drains at Newton, Mass.," as published in The Engineering RECORD under date of December 16, 1893, I would state that your editorial comment was correct.

"The plumbing ordinances were changed so that the requirements now are that there shall be a fresh-air connection with the soil pipe and a running trap between it and the house drain, except when connected with a public sewer. In that case it is optional with the householder whether he has or has not a running trap and fresh-air inlet.

"This recommendation was made in my report to the City Council on a plan for a system of sewers for the city of Newton, only after a very careful study of the best practicable plan for the ventilation of the sewers, and after receiving the approval of several of the best sanitary engineers who were consulted upon this as well as other details in the design wherein it seemed desirable to depart from the common practice.

"I might here state that the plumbing rules of the Board of Health are very complete in their requirements, and the plumbing is carefully tested by the inspector with either the water, smoke, or peppermint test, and a careful superficial examination of every fixture or trap, before any portion is covered up.

"All traps are to be ventilated and all sod pipes and vent pipes are to be carried full size through, and at least 3 feet above the roof. The sewers are carefully laid, so that every section between manholes can be and is frequently inspected by the use of mirrors reflecting light through the sewer so every joint of the pipe can be seen.

With the conditions as above described. I doubt if Mr. Clark has ever known of a case where there was a flow of air from the soil pipe into the house. On the contrary, my experience has been that should an opening occur in a ventilated soil pipe the flow of air is invariably into the pipe and not out of it.

"The introduction of a large volume of fresh air into the sewer and through the soil pipes creates conditions not only unfavorable to the life and generation of disease germs, but favorable to their destruction. It also produces conditions unfavorable to the formation of what may be known as sewer gas in any condensed or concentrated form. If the gas is created at all, it is so diluted as not to be offensive or dangerous to health.

"I have had a canvass of all the cases of scarlet fever or diphtheria which have occurred in Newton as reported to the Board of Health since August 10, 1893, and find that out of 41 cases of scarlet fever but four cases have occurred in houses connected with the sewer, and out of 25 cases of diphtheria but two cases have occurred in houses connected with the sewer.

"The cases have also occurred in sections where the sewers have either not been laid at all or laid this season only, and I do not find a single case of sickness of a person attending a school where the fresh-air inlet or running trap has been omitted."