Six page document outlining metal aeroplane construction carried out by Vickers and seven photographs depicting a sample spar for "Avro" wings; a sample spar for "Handley-Page" machines; a complete set of "Duralumin Avro" wings; a duralumin "Avro" wing; a sample spar for Vickers "Vimy" bomber; the straightness of spars and leading edge and a general view after test. Housed in the original file