EDITORIAL. 
later models, making them more convenient to use and wear, and the 
soda-lime employed as an absorbent has been supplemented by the addi- 
tion of nut charcoal and potassium permanganate, in order to protect the 
men against the numerous poison gases, such as “ tear gas,” “ sneezing 
gas,” and “mustard gas,” which followed the original chlorine gas 
attacks. 
For industrial purposes at chemical and other works, the gases likely 
to be met with are—(a) chlorine; (b) acidic gases, such as sulphur 
dioxide, nitric oxides, and prussie acid; (¢) special chemicals, such as 
formaldehyde; and -(d)- carbon monoxide. 
Chlorine and the acidic gases are readily absorbed by the soda-lime 
used in these masks, and any of the standard types can be relied on to 
protect a worker without discomfort for at least an hour in an atmo- 
sphere containing up to 1 per cent. of chlorine or the acid gases 
mentioned. - 
Formaldehyde, like acidic gases, irritates the mucous membranes 
around the eyes as well as in the throat and lungs. Goggles are here an 
essential for the protection of the eyes, and special absorbents are 
required to render the air fit for respiration in each special case. The 
difficulty, if not impossibility, of absorbing carbon monoxide puts it in a 
class by itself; and, unfortunately, its occurrence is by no means uncom- 
mon. It may be expected to be formed in any conflagration wherever 
there is insufficient oxygen for the complete combustion of the fuel. The 
Chemicals Committee is considering the question as to the desirability 
of instituting experimental work with a view to devising a mask effective 
against carbon monoxide. ° 
All fires in mines and in enclosed spaces may, therefore, not only use 
up the oxygen of the air, but also convert more or less of it into the very 
poisonous gas—carbon monoxide—and protection can only be obtained 
by the use of an apparatus which provides an independent supply of 
oxygen. 
A number of types of rescue apparatus has been devised and used for 
this purpose, and a recent report by a Committee of the British Depart- 
ment of Scientific and Industrial Research gives a very complete account 
of them, and also of the system under which they are used at. some score 
of rescue stations distributed over England and Scotland. They are all 
complicated, expensive, and heavy, and can be only little less uncomfort- 
able to wear than a complete diver’s suit, but their value lies in the fact 
that they enable work to be carried out under conditions, and in sitta- 
tions, where life would otherwise be impossible. 
“The Proto, Meco, Draeger, and Weg apparatus are all in common 
use; they weigh from 36 to 40 Ibs., and include a cylinder of compressed 
oxygen. A more recent apparatus, the Aerophor, is charged with 8 to 
10 lbs. of liquid air (60 per cent. oxygen). Several other patterns have 
been suggested or patented, but have not come into use for rescue work 
in Great Britain. 
Such rescue appliances are useless unless worn by properly-selected 
and thoroughly-instructed men, and several fatal accidents have occurred. 
The British Committee makes several recommendations as to rescue 
station routine and organisation. Expert chemical and medical control 
are essential for safety. 
327. 
