Ether : a brief account of its manufacture, chemical composition, congealing properties, etc. etc. / by Martin Henry Payne.

  • Payne, Martin Henry.
Date:
1866
Catalogue details

Licence: Public Domain Mark

Credit: Ether : a brief account of its manufacture, chemical composition, congealing properties, etc. etc. / by Martin Henry Payne. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    %^essel. This phenomenon is explained by saying that the temperature over and above 212°, whicli is requisite to keep it in ebullition, was rendered latent. The latent heat of steam is 960°-6, or in other words, if the beat disguised in steam were set at liberty, and permitted to exert its influence on the bulb of a thermometer, the mercury would rise for a similar number of degrees. Thus bodies, whether liquid or gaseous, may be considered as chemical compounds, in which, as Dr. Wilson observes, liquids consist of solids+heat, and gases of liquids-}-heat; and as chemical compounds, the elements cease to pre- sent the same properties as before combination. When bodies are passing from one state to another the requisite heat is taken from surrounding objects, in which the tempera- ture falls proportionally; and the more volatile a liquid is, the greater is the amount of heat taken in a given time from any one neighbouring body, and the less tinae have they in which to recover their equilibrium—by borrowing in their turn—• and consequently the more rapily the thermometer falls. In Dr. Richardson’s instrument, in which ether (one of the most volatile substances known) of a very low specific gravity is used, evaporation is further aided by being thrown off in the form of a veiy fine spray, thus exerting its influence over a large surface. The mercury in the bulb of an ordinary thermometer may be frozen by it in about a minute, which is about the time used in operations in Dental Surgery, and so far, at least as my own personal observation has gone—5j to i7\^lxx is the usual quantity employed; at the same time, instances occur when it is necessary to nearly double the time in order to obtain the same results. In conclusion, I will merely add that the action of the ether, as applied to Dental purposes, appears to be partly narcotic, as well as anaesthetic. In the preceding paper I have employed the new atomic weights in which the equivalents of oxygen, sulphur, and carbon have been doubled, so that the formula for water would no longer be expressed by HO, as formerly, but by IlgO or JJo. H