Copy 1

The construction and use of a thermometer for showing the extremes of temperature in the atmosphere, during the observer's absence. Together with experiments on the variations of local heat and other meteorological observations / By James Six.

  • Six, James, 1731-1793.
Date:
1794
Catalogue details

Licence: Public Domain Mark

Credit: The construction and use of a thermometer for showing the extremes of temperature in the atmosphere, during the observer's absence. Together with experiments on the variations of local heat and other meteorological observations / By James Six. Source: Wellcome Collection.

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    age we motion of the fluid to be at all retarded by any res sistance of the index, such resistance being uni- form, no error could hence arise, the scale being made under the influence of every cause, which can operate, either to accelerate or retard its mo- tion. Lastly, the necessary bulk of the spirits seems to imply that some inconvenience must arise from the body of the Thermometer and quantity of spirits being too large; and since large compact bodies are not so soon affected by change of heat and cold as small ones, it is therefore concluded that this Thermometer will not so readily shew any change of temperature as it ought to do. Now it is well known that the readiness with which bodies are liable to be affected by heat and cold, depends more on their relative surface, than their quantity. The quantity of spirit necessary for one of these largest Thermometers would something more than fill a spherical bulb of an inch and a quarter in diameter; which form would confessedly have too small a proportion of surface, and be too slowly affected by change of Tempera- ture. To obviate this, I have extended the spirit in a very thin glass tube, sixteen inches long, and but little more than a quarter of an inch in diam- eter: