FUMIGATIONS TO DESTROY CONTAGION. 349 



It will not be improper, to add to the instructions for 

 - preparing these phials the manner of using them ; for 

 things acquire value only by the skill with which they are 

 used. 



In the first place it is to be observed, that the intention Manner of 

 of the screw is chiefly to bring the cap of the case to the usnig l em * 

 proper point for confining the stopple of the phial; which 

 might otherwise be raised up by the expansion of the va- 

 pour, and allow the acid to escape; so that, if you were to 

 endeavour to turn the screw as far as it would go, or even 

 if you were to turn it with too much force, you would ne- 

 cessarily split the cap, or even crack the neck of the phial, 

 which would be still more dangerous, if it were not imme- 

 diately perceived. 



I have observed, that the first thing done by those who Caution, 

 are unacquainted with the nature of acid gasses is, to apply 

 the phial to the nose, as they would a smelling bottle ; whence 

 they feel an irritation so much the more painful, because it 

 is more quickly carried to its maximum. It is necessary 

 therefore, to inform such persons, that the phial for destroy- 

 ing contagion should not be brought near the nose: on the 

 contrary, it should be kept at a distance from it when it is 

 unstopped; and when it begins to make an impression on 

 the olfactory nerves, it is time to stop it again, unless it be 

 required to render the fumigation efficacious in a given 

 •pace, as when the object is to purify a chamber rendered 

 noisome by putrid efliuvia. In this the phial should be 

 placed on a table, and left unstopped for some minutes. 

 With these precautions we may obtain all its good effects, 

 without experiencing the least inconvenience. 



So much for the use of the portable phials : you will soon 

 see, that I have carried my views much farther respecting 

 the advantages to be derived from the preparation they 

 contain. 



Permanent Apparatus for destroying Contagi&n in Hospi- 

 tals, public Places, cj*c. 



It is with some unwillingness I employ the word appura- Permanent ap- 



ius, which may perhaps be sufficient to frighten many per- J^b^Tii 



