The puzzle picture of a radiator bearing the name “Cummins Diesel” which appeared on page 133 last month caused much speculation amongst readers. Suggestions were that we took it at Indianapolis last year (we had hoped for this one!) and that it was Fred Agabashian’s 138 m.p.h. car (Sir!); that we saw it in the B.R.M. test-house (!); that we had taken our camera with us when X-rayed in a mobile X-ray unit, and so on. All wrong! This American plant is used for pumping at the Redex establishment at Chiswick.