Accession No

1939

Brief Description

five mercury-in-glass hydrometers, by Max Kaehler and Martini, German, 1875 - 1925

Origin

Germany; Berlin

Maker

Max Kaehler and Martini

Class

physics; metrology

Earliest Date

1875

Latest Date

1925

Inscription Date

Material

glass; metal (mercury); paper (card, one other)

Dimensions

1939.1 length 290mm; max diameter 20mm; case length 332mm; diameter 26mm; 1939.2 length 320mm; max diameter 20mm; case length 351mm; diameter 27mm; 1939.3 length 320mm; max diameter 20mm; case length 352mm; diameter 27mm; 1939.4 length 310mm; max diameter 20mm; case length 353mm; diameter 27mm; 1939.5 length 338mm; max diameter 20mm; case length 362mm; diameter 27mm

Special Collection

Cavendish collection

Provenance

Transferred from the Cavendish Laboratory, University of Cambridge, from 09/1974.

Inscription

‘Max Kaehler & Martini, Berlin ‘ (on scale of each hydromater)

Description Notes

5 mercury weighted glass hydrometers. Lower bulb for mercury weight, central elongated bulb and upper tube containing paper scale. Bottom of each scale marked ‘Sp. Gew.’ and ‘Tp.15ºC.’. Each in card slip case

1939.1 scale divided 0.700 - 0.850 (specific gravity) numbered by 0.010 subdivided to 0.001. In mottled green slip case labelled ‘0.700 - 0.850’ on body and ‘0700 - 850’ on lid.
1939.2 scale divided 0.850 - 1.000 (specific gravity) numbered by 0.010 subdivided to 0.001. In mottled red slip case with label ‘0.850 - 1.000’ on body and ‘0850 - 1000 [/] F’ on lid.
1939.3 scale divided 1.000 - 1.200 numbered by 0.010 subdivided to 0.001. In mottled red slip case with label ‘1.000 - 1.200’ on body and ‘1000 - 1200 [/] F’ on lid.
1939.4 scale divided 1.600 - 1.800 numbered by 0.010 subdivided to 0.001. In mottled red slip case with label ‘1.600 - 1.800’ on body and ‘1600 - 1800 [/] F’ on lid.
1939.5 scale divided 1.800 - 2.000 numbered by 0.010 subdivided to 0.001. In mottled red slip case with label ‘1.800 - 2.000’ on body and ‘18000 - 2000 [/] F’ on lid.

Condition good (case of 1939.3 a bit battered and case of 1939.2 has hole at lower end); complete

References

Events