If formaldehyde or formic aldehyde is to be extensively used as a disinfectant, as now seems probable, it is important that the medical profession should know its limitations as well as its power, since either the use of a worthless disinfectant or the improper use of a valuable one is but little removed from a criminal act. Recent experiments indicate that only under certain conditions can we be reasonably sure of destroying pathogenic organisms by means of formaldehyde.
The compound is a gas of which the specific gravity is very nearly that of air. We should expect, therefore, that it would be slow to diffuse where air must be displaced. Pfuhl has shown (Zeit. für Hygiene, Vol. XXII, p. 339, Vol. XXIV, p. 289) that where it is present in sufficient quantities it sterilizes the surface of exposed objects, though its penetrating power is small. Similar results have been obtained