Harrogate and its resources : chemical analysis of its medicinal waters report addressed to the chairman of the Harrogate Water Committee / by A.W. Hofmann ; with an appendix, on the modes of their administration / by the Committee.

  • August Wilhelm von Hofmann
Date:
[1854]
Catalogue details

Licence: Public Domain Mark

Credit: Harrogate and its resources : chemical analysis of its medicinal waters report addressed to the chairman of the Harrogate Water Committee / by A.W. Hofmann ; with an appendix, on the modes of their administration / by the Committee. Source: Wellcome Collection.

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    the metal to enter the gas-reeeiver, until it stands at the same level, within and without the tube; the clamp is then secured again, and the mercury transferred into a graduated cylinder. The differ¬ ence between the volume of mercury, and the known capacity of the gas-receiver represents the volume of gas, at the existing barometric pressure and temperature. The only conditions necessary for the success of this apparently complicated process, are a sufficiently long ebullition, and a proper proportion in the capacities of the water-flask, and gas-receiver, which can only be attained by a few preliminary operations. The capacity of the gas-receiver must be greater than the volume of the gas in the water-flask, when measured under the ordinary pressure of the atmosphere. If the volume of the gas were greater, the gas- receiver or the caoutchouc connector might burst, and if they actually withstood the outward pressure, a certain quantity of gas would be lost on opening the clamp under mercury. The same apparatus might be used for collecting the gas intended for analysis, but unless the gas can be transferred at once into the eudiometer, it is better to construct the boiler-globe and gas-receiver of one piece of glass, and to have the ends of the receiver so far drawn out that they may be sealed by means of a' blow-pipe jet. This tube, in the moment before sealing it, is represented in Fig. 3, which requires no farther explanation. Fig. 3.
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