5 8 THE POPULAR SCIENCE MONTHLY. 



sulphuretted hydrogen is the principal deleterious gas which disinfect- 

 ants have to encounter the worst kind of vermin to ferret out. Prof. 

 Way, however, asserts that the gaseous elements that are usually foul 

 smelling and hurtful are ammoniacal. 



The best disinfectant to deal with sulphuretted hydrogen, such as 

 is evolved in the emptying of a foul ash-pit, would be salts of iron or 

 chloride of zinc. Salts of iron and copper are antiseptics and very 

 active deodorizers, and would have been used even more extensively 

 than they have been, had they been harmless. But the iron-salts 

 stain all they come iuto contact with, and copper salts are injurious to 

 life. Zinc-salts are also inimical in this latter way. A disinfectant, 

 to be available in the homes I am endeavoring to depict, must neces- 

 sarily be harmless, and until quite recently it was not easy to find 

 such an agent. The alkaline permanganates have been extolled as 

 disinfectants. They are in many instances admirable deodorizers, but 

 the fact that permanganates are sparingly soluble in water renders 

 their employment very difficult, except in dealing with small accumu- 

 lations of putrid matter. The use is too limited to enable us to rely 

 on them for systematic disinfection. 



There is one volatile deodorizer and disinfectant that has been 

 recommended very strongly in some cases by Dr. B. W. Richardson 

 and Mr. Spencer Wells, and that is iodine. In some virulent diseases 

 attended with fetid discharges, a little iodine placed in a box, with a 

 little muslin to confine it, is sufficient to render the room tolerable to 

 the attendants upon the sick. For similar purposes, peat, sea-weed, 

 wood, or animal charcoal, have been recommended, owing to the avid- 

 ity with which they condense the gases of decomposition within their 

 pores. For some years, Prof. Gamgee has used charcoal charged with 

 sulphurous acid as an active antiseptic, and he now suggests the use 

 of charcoal mixed with chloride of aluminium, or, as he popularly calls 

 it, chloralum. The sulphurous acid renders air irrespirable, but chlora- 

 lum, which is a deliquescent chloride of aluminium, attracts and neu- 

 tralizes the noxious elements of a poisoned atmosphere. 



Having attempted to show that disinfection must be an every-day 

 practice in the household, and that disinfectants must necessarily be 

 harmless antiseptic deodorizers, it is not difficult to establish a code 

 of rules of almost universal application. There is a caution that 

 should be given at all times in a household : Servants cannot be ex- 

 pected to understand the use of disinfectants any more than they can 

 be trusted to carry out a system of ventilation. Disinfection and ven 

 tilation, therefore, shoidd, to a large extent, be automatic processes 

 and, happily, such things are to be found. 



A fusion of the two processes of disinfection and ventilation has 

 been tried, of late, in the following manner : The space occupied by a 

 top pane of glass is fitted up with a piece of metal which slants from 

 the bottom upward, and the top is rounded in shape and perforated. 



