Nitrogen filled mercury thermometer, glass, scale-5-50 degrees centigrade, by F. W. Johnston and Daughter, Hendon, 1950-1978 Nitrogen filled mercury thermometer 1950-1978
Clenical mercury thermometer, uncalibrated, glass by F.W. Johnston and Daughter, Hendon, 1950-1978 Clenical mercury thermometer 1950-1978
Nitrogen filled mercury thermometers, glass, scale 0-400 degrees centigrade, by F. W. Johnston and Daughter, Hendon, 1950-1978 Nitrogen filled mercury thermometers 1950-1978
Fahrenheit clinical thermometer, glass, by F. W. Johnston and Daughter, Hendon, 1950-1978 Fahrenheit clinical thermometera, glass, by F. W. 1950-1978