Sectioned Revolution Counter MkIV a.(mechanical)
Revolution Counter MkIV by Smith
German clock type revolution counter and indicator
Sectioned Revolution Counter WD
German Revolution Counter by Morell No. 81184
Sectioned Revolution Counter MkV
Jaeger clock type revolution counter
German Revolution Counter by Dr. TL.Horn Leipzig
Revolution Counter
A revolution counter, marked Cary/London
Revolution Counter, with five discs
1858
German Revolution Counter
TEL' German revolution counter
'TEL' German Revolution Counter
Mechanical counting device, c 1900.
circa 1900
Combined Revolution counter and stop watch in case
Small Hand revolution Counter
Casagrande liquid-limit apparatus
Improved form of mechanical counter, late 19th century.
late 19th century
Aircraft engine revolution counter.
Revolution counter, inscribed with numbers
1862
revolution counter used on a waterwheel
Casagrande liquid-limit apparatus
1967
Revolution-counter measuring unit
revolution counter
1960