An otheoscope Size:L: 80 x 60cm Citroën 2CVs at an auto-cross

Citroën 2CVs at an auto-cross

yer honour-r

the print is embossed 'Charles Spencer

1937 Ford V8 model 78 Club Cabriolet

two of the new iron-clad men of war ships

An otheoscope Size:L: 80 x 60cm Citroën 2CVs at an auto-crossAn otheoscope with fixed vanes of oxidised copper and coloured disc above it. An instrument designed for measuring the mechanical effect of radiant energy, a modification of the radiometer. Mounted in a partial vacuum, the central rotor spins when the vanes are exposed to light. Chemist William Crookes (1832 1919) initially believed the vanes with black surfaces were pushed around by pressure from light radiation. This was incorrect and other theories