In the 1930s my father, a heavy smoker, had a huge, metal ash tray. This consisted of a very heavy metal base, maybe 12" diameter, into the top of which was screwed a vertical tube 2" diameter and maybe 30" long. At the top this belled out into a thing with cigarette grooves, carrying handle etc. The whole thing sat on the floor and the top was around waist high. This monster could hold months of debris in the bottom without too much smell coming out of the top!
The trunnions on the side of the present article immediately reminded me of this. Could it be from something similar - tilt to empty down the tube?
Many ash trays had the grooves inclined inwards, presumably so that fires would hopefully start inside the tray rather than outside.
Just a thought