This watercolour, “Mustangs in Readiness,” in the Museum of Civilization's collection, is Eric's 1944 depiction of Mustang fighters in England ready to intercept the enemy. In her collection of Eric's work Margaret Bridgman has a photograph of Eric standing at an easel working on this painting. Taken at face value, this photo depicts Eric completing the painting, although it could have been staged after the fact. This is not to say that Eric did not work al fresco; a clipping of a Toronto Star article by Gregory Clark (“War Artist Finds Out Eyes On Him All Time,” 1944), mentions Eric's backpack which contained a camera, paints, and water bottle, along with a hinged easel.

This photograph was in Eric's possession when he passed away in 1980, and this collection of photographs, drawings and other work was given to the care of his neice, Margaret Bridgman. They provide insights into Eric's work and methods that are missing from the collection of completed work and archives in the Crown's possession.