As I contemplated just what that canister might look like, it occurred to me that I had a small skull that was about the right size and shape. I found this partial plastic skull several years ago at a yard sale, without knowing just what I would do with it. This seems to be the right project for it.
To make it look steampunk I will need to punkify it. I want to join the natural with the mechanical, combined into a single integrated unit. I am planning on casting the skull canister in a faux pewter (cold cast aluminum), and attach it to a leather mouth and nosepiece, with leather straps.
Human teeth are laid out roughly in an arc, a shape which allows me to replace these plastic "human" teeth with gear teeth. While I rarely utilize the symbol of the gear in my work—due to its ubiquitous appearance and overuse in so many things that are called steampunk—I do think it is appropriate in this instance. In the photo above I have removed the lower jaw, flattened the back of the skull, and sanded off the upper teeth in preparation for fabricating and installing the gear teeth.