Vintage 1960s Lucas cyclometer, axle-mount. This cyclometer is calibrated for 27"/700c wheels.  
Manufactured in Birmingham, England

Please note: 
Originally made for bikes with a solid front axle but could be adapted to later model quick release-type axles.  
Original glass is missing from cyclometer display, but does not detract from operability.
These cyclometers were commonly found on solid axle road or touring bikes of this era.

This accesory was discovered hiding in my classic parts bin that I moved from our family operated shop which we closed after 75 years of business.  During the early years, we carried a variety of European bikes then in the 70's mainly Raleigh and Peugeot bicycles.

This would provide an authentic, working cyclometer for any 1960s vintage bicycle.