Drawing of machine designed by Giovanni Branca

Drawing of Machine designed by Giovanni Branca 1629, prepared in the Science Museum, 1897.

Branca was an Italian engineer who, in 1629, published a work in which he suggested a form of steam turbine. A powerful horizontal jet of steam was to be directed against vanes on the circumference of a fan wheel with a vertical axis, thus causing the wheel to revolve. Several applications of the resulting motion were described, but that shown in the drawing consists in the use of a reducing train of spur gearing by which pestles or gravitation stamps are lifted. The apparatus is now manufactured as a child's toy; with an important alteration in the form of the jet and in that of the vanes it would, however, have resembled the efficient steam turbine of Dr. de Laval, provided the requisite high speed could have been maintained.