282 WISCONSIN STATE AGRICULTURAL SOCIETY, 
pipes to them; but the consequences of such an arrangement are 
most disastrous, since the sewer air, when forced back in the pipes 
from any cause whatever, will be sure to find its way through the 
hydraulic traps, and permeate the atmosphere of the entire house. 
A safer plan is to disconnect the waste pipes inside the house from 
the street sewers, by allowing the former to discharge their contents 
into a chamber or tank, covered and properly ventilated, or, what 
will answer equally well, is a trap placed in the sewer, as near the 
outer wall as practicable, provided with a ventilating pipe, about 
four inches in diameter, running from it to the roof of the house, 
thus placing the poison beyond the power to do harm, and effectu¬ 
ally preventing the passage of sewer-gas into the house. 
SUMMARY OF VENTILATION. 
All waste pipes of the house are to be disconnected from the 
sewer outside by means of chambers, tanks or traps, as near the 
outside wall as practicable, with ventilating pipes extending to the 
roof. 
Rain-water pipes should never be relied upon as ventilators, since 
when they are most needed they are performing their own specific 
duties. 
The soil pipes of closets should invariably have ventilating pipes 
running from each trap to the roof of the building, or into chimneys. 
Every trap in the waste pipes inside the house should have a 
ventilating pipe, since even in waste pipes for the conduct of water 
only, the air will become foul. 
The masses are slow to believe that the products of decomposi¬ 
tion of animal and vegetable matter, generated in such small quan¬ 
tities that they cannot be recognized by the senses, can possibly 
give type and malignancy to disease. It is, however, a well known 
fact among medical men that an exceedingly small amount of sewer- 
gas, added to the natural causes which must inevitably surround 
us, may and does give a fearful malignancy to disease. 
For instance, the natural causes with which we are brought in 
contact may produce diarrhoea, intermitting and remitting fevers, 
catarrhal difficulties, etc., which are, as a rule, easily controlled and 
seldom prove dangerous to life; but if we add a very small amount 
of the product of decomposition to the causes which have produced 
the above named diseases, we shall have instead, typhoid fever, 
