Hints from the Health Department. Leaflet from the archive of the Society of Medical Officers of Health. Credit: Wellcome Collection, London
[Report of the Medical Officer of Health for London County Council]
From this last Table XVIIIa, it follows that the disinfecting power of Condy's fluid,
even when used in the proportion of five teaspoonfuls to one pint of water, remained practically
negative in our experiments. Whether this result is due to the disinfecting power of the fluid
being consumed in the oxydising of the organic matter submitted with the microbes, we are
unable to say.
Series III.—Corrosive Sublimate.
This was used according to the formula of the Local 'Government Board; 1 in 1,000.
Time of exposure 24 hours.
Table XIX. gives the results of the culture ami experiment after exposure; as might be expected, all microbes, including the spores of anthrax and the tubercular sputum, had been killed by the solution.
|Bacillus typhosus||On all materials|
|Spores of bacillus anthracis||„||-|
This was used in the form of a one per cent. solution. Time of exposure 1 hour. The result of the experiment is shown in Table XX.
|Nature of microbe.||Nature of material.||Result of culture and experiment after exposure.|
|Bacillus typhosus||On wood|
|Bacillus pyocyaneus||On wood||—|
|Vibrio choleræ||On wood||—|
|Staphylococcus aureus ...||On wood|
|Spores of bacillus anthracis||On wood|
|Tubercular sputum||On wood|
The result of this experiment is then this: a 1 per cent. solution of the bleaching
powder is capable in one hour of disinfecting the spores of bacillus anthracis on paper and on
linen, an effect more favourable than that obtained with a 5 per cent. solution of carbolic acid
or five times Condy, even after an exposure of 24 hours.
The experiment with the 1 per cent. solution of bleaching powder was repeated, this
time leaving the materials 24 hours in the solution.
Table XXa gives the results of this series.
* Bleaching powder is a mixture of calcium chloride, CaCl2 and calcium hypochlorite, CaCl2O2. It in sometimes called
chloride of lime and sometimes calcium hypochlorite. The substance used in our experiments is the article employed in commerce for
bleaching purposes, and which is also largely used as a disinfectant and deodorant.