Course of lectures on army sanitation / by C.H. Melville.

  • Melville, C. H. (Charles Henderson)
Date:
1911
Catalogue details

Licence: In copyright

Credit: Course of lectures on army sanitation / by C.H. Melville. Source: Wellcome Collection.

    48/94 page 208
    different posts on the lines of communications. On the other hand, the hlter cart is suitable for troops where good roads are available, and can be modified for mule or coolie transport under less favourable conditions. Quite lately the ultra-violet rays of the spectrum have been utilised for the purpose of sterilizing water. The method is undoubtedly effica- cious. It demands a source of electric power, and an expensive and some- what fragile lamp. As in other cases, the water must be clarified first. I have not seen a portable form, but I believe this exists, or has at least been suggested, in the German Army. The efficacy of this method, its rapidity of output, and the small amount of supervision required, combine to give it great value, especially under certain circumstances, such as in standing camps, general hospitals, etc. This method possesses in addition the great recommendation that it in no way alters the composition or taste of the water. A full description of the Westinghouse Steriliser, working on this principle, may be found in the Journal of the Royal Army Medical Corps, for February, 1911. Various chemicals have been used for the purpose of sterilising water. Amongst these may be mentioned permanganate of potash, sulphate of soda, and the haloids (chlorine, bromine, and iodine), evolved from salts of these elements. Permanganate of potash has been widely used in India. In the absence of any other oxidizable matter it appears to have a certain inhibitory effect on the growth of bacteria. It cannot be relied on, however, except in quan- tities which render the water unpleasant to the sight and taste. Acid sulphate of soda, in a strength of 15 grs. to the pint, can be relied on to kill the ordinary disease producing organism. It is obvious, however, that if a man drinks at all freely of such water, he at the same time ingests a distinctly large amount of a possibly injurious drug. Such a dose might be tolerated for a few days, but prolonged use would undoubtedly result in digestive disturbance. Chlorine is, as a rule, evolved from bleaching powder, bromine from tablets of the bromide of potash, and iodine from the iodide and iodate of soda by the action of tartaric acid. In all cases some means of reabsorption of the free chlorine, bromine, or iodine, is necessary before the water can be considered fit for consump- tion. Thus, for instance, in the case of iodine (Vaillard’s process), two tablets, one containing iodide of potash and iodate of soda, and the other tartaric acid, are added to the water. Free iodine is thus evolved, and after ten minutes have elapsed a tablet of hypo-sulphite of soda is added to absorb the iodine. The complication of this process is sufficient to condemn it for general use. The ordinary soldier cannot be expected to remember the exact order in which the tablets are to be added, nor if he is very thirsty is he likely to be meticulously observant of the length of time he allows for the evolution and action of the iodine. On a large
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