As was widely announced in the picture-houses of the United Kingdom at the close of 1936:
THERE IS NO DEFENCE AGAINST POISON GAS
This is from a book by the German exile and novelist Heinz Liepmann, Death from the Skies: A Study of Gas and Microbial Warfare (London: Martin Secker & Warburg, 1937), 273. There's no more information than that. What could he be referring to? A film? Newsreel? Advertisement? Public service announcement? Maybe it's from the 1936 political film Hell Unltd. The BFI describes it as follows:
Hell Unltd. links government's preoccupation with armaments to a likelihood of war, and relates this to the First World War. Stock footage of the horrors of this war is shown, while titles such as "die" and "to make a world safe for democracy" are displayed. This combination of titles and image is intended to show the negative effects of war and to condemn a government committing itself to further warfare.
On the other hand, it's also described as a 'heavily experimental' film, which seems an unlikely candidate to 'widely announce' anything. So what else might it be from?