Physiological essays and observations ... / [John Stedman].

  • Stedman, John, -1791.
Date:
1769
Catalogue details

Licence: Public Domain Mark

Credit: Physiological essays and observations ... / [John Stedman]. Source: Wellcome Collection.

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    The frame ought to be fupported by four feet, one at the extremity of each branch; and, that the reflexion of heat from the table or floor, on which the frame ftands, may not affed the mercury, thefe feet ought to be four inches high at leaft. The frame being thus prepared, the four candles, fixed in the fockets, are to be placed at the divifions next to the extremi¬ ties of the branches, and a thermometer ■»_ . to be hung, precifely over the central point of the frame, fo high that its ball may be in an horizontal plane with the flames of the candles. Having obferyed the pre- cife height at which the mercury ftands by the heat of the candles at the mod diftant {ration, let the fockets and candles be moved to the next ftation, and fo on through the twelve ftations. But in this procefs there are feveral precautions which ought to be carefully attended to. O 2 1. The