A colorless, odorless liquid, made by boiling phosphorus with nitric acid and water, and having a strength of 85 per cent. It is very acid, but does not corrode the tissues. Its physiological effects are unimportant - mildly tonic and astringent.
2 mils, well diluted.
Made by heating sulphuric acid with charcoal. Sulphurous-acid gas results, and is dissolved in water, constituting 6 per cent. of the solution. A colorless liquid with pungent sulphurous odor. Sulphurous-acid gas 6.4 per cent. is obtained by the combustion of roll sulphur, and was formerly used in disinfecting rooms. This form of disinfection, formerly believed to be efficient, is now known to be useless in so far as pathogenic bacteria are concerned, and boards of health are abandoning its use after contagious disease, though no faster than the advance in popular education on such lines. It is, however, of real value in ridding a room or ward of bedbugs, if these pests have lodged in the walls or woodwork, and for this purpose steam is not necessary. It is a specific for all forms of lower animal life - not bacteria.