"We come now to the nose irritants and the vesicants. To speak of these gases as nose irritants is not quite correct in so much as their fånge of damage extends far beyond the nose. The more correct name for this group would be the blister Bases. These may be gases, solids or liquids which damage any part of ihe body with which they come into contact. The chief effects of these gases are acute conjunctivitis, dai age to the nose, nausea, vomiting. burning of the exposed surfaces of the body, and this is followed by severe blistering and. inflammation of the trachea and the bronchi.
"When we think of this group of gases the first name that jumps into my mind is the name of mustard gas, dichlorodiethyl sulphide. This gas was used extensively during the last war and did considerable damage before the means of combatting it were fully developed. It was the only gas of this type then used. It is thought that if gas warfare develops to any great extent in this present war that this gas will again be used. But we can assure ourselves of this, that the authorities are well prepared for its reception and there is no danger of "While asa chemical compound mustard gas is fairly staple, yet it is possible to decompose it with a fair measure of ease. It is hydroused by boiling water or by steam and it is decomposed by chlorination. These point the way to decontamiinating the areas affected. In some places where hot water and steam is available in emergencies, that is in factories, a steam hose or hot water from boilers may do the necessary. But the main work, of decontamination will be dong through extensive washings of the' areas affected with chloride of lime solutions. Mustard gas is a very poisonous substance but its action is local—that is—it is a direct irritant to the skin and the mucous membranes. Another gas of the same type is lewisite the chemical name of which is rather formidable Chlorovinyl-dichloro-arsine.
Fumes or Smoke "Then we come to another form of gas which might be termed a fume' or a smoke.' This class of gas may be considered to be derivatives of arsine, an arsenic and hydro-
Text read from the printed page and cleaned; old type leaves the occasional error.