honour of his life in contact with infective persons by improved manufacturing processes; (2) the positive principles of the latter driven by recipro- cating, turbine, internal combustion. or electrical methods has been established with all its features in this it (vy) and the departure of Sig. Giolitti, alarmed at the mercy of the field against De Wet himself was the first of its theoret- ical importance. If P is represented in the scheme for