IN conformity with requests at different times of commissions appointed by three cities for the revision of their plumbing regulations, and acting as expert for these commissions, I have drawn up several codes and give herewith one embodying the best points.

I have before me copies of the codes of thirty-seven cities and towns, seventeen of which embody the simpler and more modern and scientific principles, omitting the requirement for the back venting of traps. The rest adhere to the antiquated methods advocated a quarter of a century ago when the experiments of Hellyer, and of Bowditch and Philbrick were published, which seem to have been largely responsible for the present complication. Their recommendations, which might have had some excuse at that time, are no longer applicable to the present conditions.

Greatly improved methods, materials and appliances in plumbing have entirely altered the data. Main stacks of soil and waste pipes are now universally ventilated from top to bottom, as was not the case at that time. Fixtures are constructed with better flushing devices. Large drum and other traps have been found to be secure against syphonage and back pressure and evaporation without back venting. Means of keeping the air of sewers and drains well aerated and perfectly safe have been devised, and we know more about the constitution of sewer air and what can be done to render it innocuous than we did in those days.

I have given in the previous pages my reasons for the various improvements I have advocated in my proposed code, and will only call especial attention here to section 7, calling for an equally rigid standard test to be applied to back vented syphon traps, as well as to unvented anti-syphon traps, before either shall be accepted as an adequate protection against syphonage, back pressure, evaporation or clogging.

Such an impartial test has never to my knowledge heretofore been required by any plumbing regulations.

Yet in the light of our present knowledge of the undisputed unreliability of back venting in many cases, and of the equally undisputed much greater if not entire reliability of the anti-syphon trap system in all cases, what can be more absurd and unscientific than the omission of the requirement of a standard test for the former when it is rigidly exacted for the latter?

I would also here call attention to the fact that in most plumbing codes most of the knotty questions, such as the efficiency of any particular form of trap or system of trapping, or the advisability of omitting the main house trap, and others of like import, are slurred over by providing that they shall be left to the judgment of the inspector, building commissioner or board of health officer in charge. Yet what is more evident than that such an individual is not only incapable of settling questions which the highest authorities have as yet not all agreed upon or which could not from the nature of things be decided without a standard test? An impartial and exhaustive expert investigation is requisite properly to determine many of these questions. Public officials have sometimes held office for political reasons and for short periods, and they stand always under more or less pressure of influence or favoritism.

Standard tests should always be called for in all cases where tests alone can demonstrate the fitness of any device or principle, and when exacted they should be of such a kind as to determine the data required both scientifically and positively. Sanitary plumbing must cease to be considered a subject for off-hand judgment or guesswork. It is an exact science and must be treated scientifically or the public will continue to suffer inconvenience and ill health and pay twice as much for the work as is necessary or desirable.

Boards of health and plumbing inspection should be required to equip themselves with apparatus suitable to make the standard tests. The outlay would save nearly half the cost of plumbing to the public and would itself cost less than the back venting of a single small building.

I also call attention here to my section on Cast Iron Pipe Jointing. In some plumbing codes today the jointing of cast iron pipes is limited to the ordinary lead and oakum calked bell and spigot joint, which many of the best authorities today believe to be one of the worst forms of construction possible.

Some codes go further and specifically debar all "cement" joints. Now such a rule debars all steam fitters' and gas pipers' red or white lead and oil cements and the use of all of the other useful compounds now classed under the name of "cements," such as rubber cement, iron and sal ammoniac cement, and every kind of oil cement whether elastic or rigid. The word "cement" is applied to all binding materials used for cementing or binding bodies together. The dictionaries and standard works on cements, such as Standages', Phin's and Dawidowski's, include all binding materials as cements, and classify them according to their qualities, principal constituents or to the materials they unite, such as oil cements, rubber cements, red or white lead cements, elastic cements, heat resisting cements, earthenware and iron jointing cements, sal ammoniac cements, steam and gas fitters' cements, lime and stone cements, etc. These are all better than the calked lead joint, and for the public to allow them all to be debarred on account of the prejudice or ignorance of the law maker is absurd and childish, depriving themselves of all that is best and discouraging invention, on the vain and preposterous assumption that their wisdom or that of their law maker embraces everything possible whether of the past, present or future.

William Paul Gerhard, the eminent sanitary engineer, who has done so much by his careful study and writing on sanitary engineering in removing popular prejudices in this domain, writes in a lecture delivered before the Vermont Association of Health Officers*: "Back-air pipes are liable to stop up at the crown or upper bend of the trap from congealed grease or other semi-solid matter. They then become inoperative, and hence give a false sense of security. In Cologne, Germany, all back-air pipes which an investigating committee had cut open, were found choked with either grease or coffee grounds or cobwebs. In St. Paul, Minn., an examination by a plumbing inspector showed that from a total of twenty-three houses twelve houses had the vent pipes from kitchen sink traps completely stopped up by congealed grease and particles of vegetable matter, or lint from kitchen towels. Of the eleven others, only one house had a sink vent-pipe which was perfectly clear and unobstructed, and this was found to be due to the fact that hot water and lye was used once a month in the pipes. In seven out of eleven houses a soft, slimy substance was found adhering to the interior of the vent pipes for two or three inches above the crown of the trap, and in the other three the vents were partially stopped up. The vent from the S trap under the kitchen sink in my own house has been found partially stopped up five times in ten years, and would doubtless have become entirely stopped up before the end of this period if I did not have same cleaned once a year.