In the Milroy Lectures of this year, Professor Hewlett stated:—“There is some evidence to show that the germicidal power of emulsified disinfectants is greater than can be accounted for by the activity of the active constituent and theoretically seems likely, but we want some reliable experimental work in confirmation. It is ture that Chick and Martin have compared the germicidal value of higher tar acids emulsified in water and dissolved in alcohol, their results showing that the emulsified form was much more active; but the reliability of this work is vitiated by the fact that they have entirely failed to take into account the influence of alcohol in decreasing germicidal activity; for example in the case of phenol, which I dealt with in my last lecture”.