Add to albumThis type of deep sea, self-registering thermometer was patented in 1874 by Negretti & Zambra, scientific instrument makers based in London. It attempted to get round the problems encountered with the Six thermometer, by working on the principle of registering the temperature by reversing the thermometer. It was made in both straight and U-forms.
The protected-bulb thermometer is in the shape of an inverted U; at the required depth, the thermometer reversed, causing the mercury to move into the other limb of the tube. At that point, a small glass plug floated into the neck of the siphon, preventing any more mercury emerging from the bulb, whatever the subsequent temperature.
Examples of the new instrument were sent for trials aboard HMS 'Challenger'. When in 1875 her captain Captain George Nares FRS (1831-1915) was detached from 'Challenger' to lead the Arctic expedition in HMS 'Alert' he took some of the new apparatus with him. This example is marked 'POLAR EXPDTN 1875'.
Record details
To search on related items, click any underlined text below.
- Online ID: 000-180-000-975-C
- Image Rights Holder: National Museums Scotland
- Project:
National Museums Scotland Part 2
Project description View all records in project
- Ref: National Museums Scotland T.1911.62
- Date: 1874
- Material: Copper case. Inscription: No. 126, [upward pointing arrow] 17 [Admiralty mark]
Specimen / nautical instrument / meteorological instrument / the
- Dimensions:
- What: Specimen / nautical instrument / meteorological instrument / the
- Subject: 22. PHYSICS, Heat (Departmental Classification)
- Who: Admiralty (Owner)
Negretti and Zambra, London (Instrument maker)
- Where: England, London
- Event: Polar Expedition
- Description: One of a collection of surveying, nautical, astronomical, meteorological and drawing instruments - a deep sea pattern thermometer, marked, in a copper case, as used on the Polar Expedition, 1875
- References:
- McConnell, Anita. No sea too deep: The history of oceanographic instruments. Bristol: Hilger, 1982, pp 95-7
- Negretti, Henry. Negretti & Zambra's Patent Recording and Deep-sea Thermometer. Report of the British Association for the Advancement of Science, 1874, pp 43-4
- Patent Abridgements for Philosophical Instruments, no 109 for 1874
- Translations:
- Related Records: