Description

“Morris’s Patent” Chartometer in a fitted box. Hinged front to allow insertion of appropriate scale card. Used to measure the precise length of curved or straight lines on maps and plans. A small wheel at the base is rolled along a line on a map or plan. This wheel drives a needle pointer that indicates the distance directly on the inserted scale card. There are are four scale cards: 1/500; 1/2500; 6 inches to a mile; and 2 and 4 miles to the inch (there may have been nine cards originally).

This model includes a “totaliser” – a smaller secondary dial that counts the number of full revolutions of the main needle, allowing for much longer distance measurements. Image 3 shows the chartometer with a the scale card removed showing the “totaliser” to the right of the centre (displaying a red “1”)

The chartometer was patented by Edward Russell Morris of Birmingham UK in 1873.

The chartometer belonged to Professor Roland Paxton.