Dr. Baxter's report on an experimental study of certain disinfectants.

  • Baxter, Evan Buchanan, 1844-1885.
Date:
[1875]
Catalogue details

Licence: Public Domain Mark

Credit: Dr. Baxter's report on an experimental study of certain disinfectants. 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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    APILN.0'6' ways, and dogmatic assertions have been made concerning their relative On Disinfectants, usefulness; and yet it is singular, when the matter is looked into, how by Dr. Baxter. SCanty is our knowledge about their real disinfectant power, as tested by the only method capable of yielding absolute results. In the experiments hereafter to be described, Calvert’s purest crystalline carbolic acid was used, dissolved in distilled water. The solutions of potassic permanganate were prepared by weighing the crystalline salt, and dissolving it in distilled water at the moment of use. Chlorine was generated in the usual manner from hydrochloric acid and manganese dioxide ; the solution was preserved in a black bottle, duly stoppered, and kept cold. The sulphur dioxide was obtained by the action of concentrated sulphuric acid on copper turnings. The solutions of chlorine and sulphur dioxide were invariably titrated after each experiment; the former with potassic iodide and decinormal solution of sodic hyposulphite, the latter with decinormal solution of iodine. They were always used as fresh as possible, and seldom kept for more than a week. f r'tmUmciiu'y The contagia selected for disinfection were vaccine, the virus of these agents. * infective inflammation in guinea-pigs, and the virus of glanders. A series of experiments with the virus of ovine variola was projected, but not carried out, owing to a difficulty in obtaining a supply of material for starting the inoculations. It need hardly be said that the choice of these three infective substances was chiefly determined by reasons of expediency. Any results obtained from experiments with vaccine lymph owe their practical value to the pathological affinity between cow-pox and small-pox. Further, vaccine is the only specific virus with which experiments can legitimately be conducted on the human subject. Again, it is one of the few communicable diseases concerning whose intimate pathology we possess definite experimental data of high value. This last advantage is shared by glanders, a disease eminently communi- cable both by contagion and infection, producing specific dynamical and structural effects, and having the additional recommendation, that while it admits of being studied by inoculation on certain of the lower animals, it is also susceptible of being communicated to man in its most virulent form. The virus of infective inflammation in guinea-pigs stands in a some- what different position. For we are able to generate it de novo; and so far it cannot be regarded as specific, in the proper sense of the term. But it is endowed with what has previously been noticed as the dis- tinctive mark of a virus, viz., the faculty of undergoing indefinite multi- plication in the infected organism. Moreover, it produces pathological results which are tolerably definite and constant, depending only to a limited extent, if at all, on the amount of material introduced. So that, for our purposes, it may be said to resemble the specific contagia more than it differs from them.; and it has this practical advantage in its favour, that it can be procured in considerable quantity, allowing expe- riments to be repeated and varied to a greater extent than those with vaccine or the virus of glanders. Theoretical It may be well to state that the main object of such an inquiry as the presenlfinvesti- present one is to furnish materials for the theoretic basis on which all gtttion. practical rules for disinfection must rest. We do not certainly know that any of the agents habitually employed possess real disinfectant power; we have no experimental data as regards their comparative efficiency and the various circumstances which must modify their ope- ration in particular instances. The present Report can do no more than furnish a nucleus of positive observations, limited in intention and still more in execution, round which facts of the same order may here-