Note 7 — Chapter VIII · FORM—Continued. TOOLS AND IMPLEMENTS SHAPED FOR EFFICIENCY

The turret principle is embodied in drills and a variety of other machines. It was adopted in remarkable fashion by John Ericsson in his Monitor, launched in 1862 for service in the Civil War. Because this vessel had to navigate shallow streams, its draft was limited to eleven feet. As it was thus impossible to carry the burden of armor necessary to protect a high-sided vessel, he was obliged to design a sunken hull. Guns and gunner were protected within a covered cylindrical turret which as it turned on its vertical axis, delivered an all-round fire while the Monitor stood still. Ericsson’s original turret, and its later modifications in the leading navies of the world, are described in the Life of John Ericsson, by William Conant Church, New York, Scribner, 1890.

Ericsson’s Monitor.