THE large number of publications in Germany dealing with all aspects of gas warfare which have appeared during the last two years is well known to all in touch with the German technical press, and increasing attention has been devoted to this matter in Great Britain also in recent months. The pamphlet entitled “The Menace of Aerial Gas Bombardment“by Lieut.-Col. N. G. Thwaites, which has now been issued by the New Commonwealth, is a welcome statement of the facts in a matter in which conflicting expert opinions have confused the public mind. Reviewing the situation in the different countries of Europe, Col. Thwaites points out that the danger of gas attack from the air is taken very seriously by Germany, France and Italy, while Russia is openly preparing for chemical warfare. In Germany no opportunity is lost of educating the public in anti-gas precautions, and a widely circulated “Handbook of Air Defence“was issued in May 1934. Equipment of the public with gas masks has not yet proceeded very far. In France the public has been made aware of the danger of aerial gas attack, and gas masks are now being sold in large quantities after testing by the authorities. In Italy, anti-gas precautions are dominant among the measures taken for defence against air attack, and the supply and distribution of gas masks has been carried further than in other countries; in Poland a League for Aerial Defence against Gas receives strong support from the Government.