Can you telll what this item is, what it does (did)?
Thanks,
Did you stick your tongue inside that small silver hole? 
Looks like possible dry-wood termite damage to the wood
Looks to me to be a fuse holder from Knob and tube time .pre 1950s.
I think the timber is hand hued from pre 1930s.
Typical timber see it all the time.
I do not think termites have made it to Barrie yet.
… Cookie
That is a 30’s or 40’s vintage nonmetallic lighting rosette, mostly used in barns. Mounted in that orientation as pictured, it is to be used with a porcelain fitting on a nearby beam called a “ceiling button” to swag the wire over to and hang the light.
Thanks for the replies. Good info.