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HOME HYGIENE. 



of the muscles. Two died in twenty-four 

 hours." These cases are clearly extreme. The 

 common effects of the admission of sewer-gas 

 into bedchambers and dwellings are noticed in 

 a feeling of languor, depression of spirits, sal- 

 lowness of the skin, and loss of appetite, and 

 if the cause be long continued, great debility, 

 and finally anemia, due to a changed condition 

 of the blood. These effects are analogous to 

 those produced by tbat indefinable poison 

 known as "malarial" ; and if the city in which 

 the house is situated be located in a malarious 

 district, these symptoms may indeed be refer- 

 red to malaria a convenient catch-word for all 

 diseases of obscure origin. Sewer-air, being 

 usually but little charged with carbonic acid, 

 is lighter than the atmosphere, and in conse- 



quence it ascends. Its ascension is materially 

 hastened when there is pressure from behind, 

 as is the case where sewers located on the 

 seashore are affected by the tides. The back 

 pressure is the important factor in forcing the 

 sewer-air through the water-seal of the trap, 

 and it is this which renders it necessary that 

 the soil-pipe should be continued through the 

 roof in order to allow its escape without bub- 

 bling through the water-seal. The trap venti- 

 lation-pipe need not be of very large size, as 

 it is only necessary as a means of outlet for 

 the gases escaping from the trap, the me- 

 phitic gases from the closet-bowls, and to pre- 

 vent the accident known as siphoning. This 

 accident occurs frequently in private dwell- 

 ings where the soil-pipe is of small size, as 



FIG. 6. 



the rapid passage of a 

 considerable body of 

 water creates a suc- 

 tion in many instances 

 sufficient to withdraw 

 all the water from the 

 trap. Siphoning is im- 

 possible when the soil-pipe is continued up- 

 ward, and communicates with the external air. 

 8. House- Drainage. If it be important that 

 the house shall be well ventilated, it is essential- 

 ly important that it shall be well drained, as 



diseasss from imperfect drainage are even more 

 frequent than those from imperfect ventilation. 

 It is not proposed in this article to touch upon 

 the question of sewerage of cities and towns, 

 inasmuch as they usually have in their employ 

 competent engineers. But in the construction 

 of dwellings it is rare that the drainage re- 

 ceives the consideration that it should, as in 

 building ordinary houses an architect is too 

 rarely consulted the plans of the building 

 being devised by the householder himself, or 

 by the mechanic who is to construct the work. 



