An experimental inquiry into the pathology and treatment of asphyxia ... To which the Royal Humane Society awarded the Fothergillian Gold Medal / [John Eric Erichsen].

  • Erichsen, John Eric, 1818-1896.
Date:
1845
Catalogue details

Licence: Public Domain Mark

Credit: An experimental inquiry into the pathology and treatment of asphyxia ... To which the Royal Humane Society awarded the Fothergillian Gold Medal / [John Eric Erichsen]. Source: Wellcome Collection.

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    400°—so that within a few seconds after applying the flame of a spirit- lamp, or of a gas jet, to a glass vessel containing the mixture, the gas begins to come away. “ The quantity of gas which can be procured within a given time is the point of greatest importance in reference to its medical applica¬ tion, and this will depend entirely upon the amount of material heated at once. “ Two retorts of 12 oz. liquid capacity, heated by argand or rose burners, would suffice to obtain the gas at this rate, 300 or 400 cubic inches per minute. Should it be thought desirable to have it supplied in larger quantity, it would only be necessary to enlarge the containing vessel, which in no supposable case need be of formidable dimensions. The retorts, with a view to convenience and economy, might be con¬ structed of sheet brass or iron, and could be heated by gas-burners in the ordinary way, by gas burned above wire-gauze, or by placing them at some little distance over a common fire. In every case it would be desirable to have at least two similar generators, so that, when the contents of the one were exhausted, the other might imme¬ diately be substituted for it, while it was refilled. “ The proportion of metallic oxide recommended to be added is a tenth of the weight of the chlorate ; but, from experiments made in my laboratory by my assistant, Mr. David Forbes, it appears that the quantity of oxide may be advantageously increased, and that the chlo¬ rate yields its oxygen most freely when mixed with a fourth or a fifth of its weight of the oxide. “ Although the metallic oxide suffers no change, and may be used over and over again any number of times, provided it be heated to redness after the chloride of potassium resulting from the decompo¬ sition of the chlorate has been washed from it, its action is not so purely mechanical that it can be replaced by other inert bodies. Nei¬ ther sand nor clay, in a state of coarse or fine division, has any effect in increasing the evolution of oxygen from the chlorate, which is so far to be regretted, as their cheapness and abundance would have made them preferable to the rarer and more expensive oxides; but, after all, oxide of iron is not very costly. “ What I should propose then, is, that at our public hospitals, lying-in institutions, humane societies’ rooms, police-office stations, and where- ever else cases of asphyxia frequently come before the medical officers, the mixture of chlorate and metallic oxide should be kept ready for use. Along with it there should be provided glass or metallic retorts, with suitable arrangements for heating them, and one or more gas¬ holders to receive the gas. The best form of gas-holder, I believe, wrould be that adopted at the gas-works, viz., a cylinder or drum of sheet metal, closed at one extremity, suspended with the mouth down¬ wards in a cylinder like itself inverted, filled with water. The drum being hung by chains passing over pullies and terminating in counter¬ poising weights, is filled with water by sinking it in the lower cylinder