File:Topographic Map of Duck and Riding Mountains in North Western Manitoba (1888) (3719865737).jpg

Tyrrell, J. B. and B. A. Dowling. Topographic Map of Duck and Riding Mountains in North Western Manitoba [map]. 1:506,880. Montreal: Dawson Brothers, 1888.

Map by J.B. Tyrrell, B.A., F.G.S. Assisted by D.B. Dowling, B.A. Sc. to illustrate Part E Annual Report 1887. Geological & Natural History Survey of Canada Alfred R.C. Selwyn, C.M.G., L.L.D., F.R.S., Director.

Compiled from plans of Dominion Lands, Indian Reserves, Timber Limits and Railways and from Surveys made by the Geological Corps in 1887. Heavy lines represent Gravel Ridges.

Contour lines are well adapted for showing the relief of the area along the Manitoba Escarpment. Indeed some of the beach ridges come close to being natural contours themselves. This map of Duck and Riding Mountains is probably the earliest published contour map of any part of Manitoba. It was prepared by two geologists, J.B. Tyrrell and D.B. Dowling, and is a remarkable and even audacious use of contours in the 1880s, when one considers that the area covered was large and heavily wooded, making travel and observations difficult. Tyrrell and Dowling did a fine job of mapping the streams heading in the Duck Mountains, such as the Valley and Shell rivers, and Minitonas Hill is beautifully drawn. The pass through the Escarpment between the Riding and Duck Mountains at Valley river and Short creek is clearly evident, and trails are well marked. This map was based on the railroad surveys and one summer of field work by Tyrrell and Dowling. Altitudes were determined by taking reqular barometer readings. (Warkentin and Ruggles. Historical Atlas of Manitoba. map 122, p. 286)