British Airship R34
In a recent clearout of my parent’s house, I was reacquainted with these old encyclopaedias, which my grandfather had bought as a set in 1919, just after World War One. Not surprisingly, much of the content relates to military advances made during the so-called Great War. I remember seeing these encyclopaedias as a child, my father having brought them home from his father's in the late 1950s. I can't recall him referring to them very often, but no doubt these dusty old volume’s would have been a much treasured items during the post-war period.
This book fell open at this page, showing a superbly detailed drawing of British built airship R.34. The airship, one of the largest and most advanced of its time was built between 1917 and 1918.
More about R.34 here: