Horizontal sundial adjustable for accurate reading at multiple latitudes

Abstract From the Canadian patent

A horizontal sundial constructed to accurately tell time at a specific latitude, having female threads incorporated into both the north and south sides of the dial plate. Threadedly matched male gnomon angle-adjusting bolts serve to raise either the north or, the south end of the dial plate and gnomon. This serves to bring the gnomon to the same, angle with the horizontal as the latitude of intended use. The female threads can be located, on the face of the dial plate to establish a simple mathematical relationship such that a one, degree change in gnomon elevation will correspond to a whole number of revolutions of, the gnomon angle-adjusting bolts.