1870.] REVIEWS AND NOTICES OF BOOKS. 95 



" symbol of abundance and extravagance. The mechanism must 

 '' be very excellent, and, with the best, a little chemical assistance 

 *^ from disinfectants is often needful. Water-closets which are 

 " not carefully attended to are unsafe. It is an immense advance 

 " upon the old cess-pools, which were found after much loss of 

 " life to be manufactures of disease of the most active nature. 

 " But unless we get good sewers, we have similar evils from the 

 " water system. ' There are sewers and sewers.' The liquid 

 '' matter, when neither removed rapidly, nor disinfected, is our 

 " old enemy, the cess-pool, with a territory extending miles long 

 " instead of feet. The midden is better than the bad sewer. I 

 " believe we shall never see the extinction of either middens or 

 " water-closets; we may remedy some of the evils. To allow 

 " bad air to form in the sewers, and then draw it into the houses, 

 " or permit it to rush into the streets, is bad engineering. The 

 " sewers may be ventilated, and filtered through charcoal ; or the 

 " formation of bad air may be prevented by a proper use of disin- 

 " fectants." On the earth closet question, our author remarks : — 

 " One may very correctly look upon the soil as the greatest agent 

 " for purifying and disinfecting. Disinfection by its means is per- 

 " feet so long as the decomposing matter can be perfectly dried 

 " up by it ; but, should moisture be in excess, a dangerous 

 " condition of malaria is apt to ensue." Admitting the conditions 

 which Mr. Moule lays down, viz., two cwt. of dry earth per week 

 for six persons, he says : — '* Nobody can doubt the disinfecting 

 *' power ot the soil, and certainly, Mr. Moule has found a mode 

 '' of applying it in many cases." 



The author's treatise is rendered especially valuable by a series 

 of original experiments on the comparative power of disinfectants, 

 which are expressed in a tabular form, for which our space is too 

 limited. The objects of the experiments, however, may be thus 

 stated : — 



1st. To show the amount of gas evolved when the disinfect- 

 ants act on organic substances in water. 



2nd. To show the amount of certain disinfectants required to 

 prevent the evolution of sulphuretted hydrogen. 



3rd. Amount of certain disinfectants required to remove 

 putrid smells. 



4th. Influence of volatile substances in preventing putrefaction. 



5th. Comparative power of antiseptics in preserving meat. 



6th. The antiseptic effects of certain gases on flesh. 



