I call it my duster pump. Salaman calls it a dust bellows, and says it 
is a piano or organ maker's tool for dusting inaccessible places. I 
found  mine at a garage sale almost 50 years ago while living in 
Winnipeg. Knew it might be useful. Also purchased at that time were a 
couple of user-made planes for gutters and curves, since sold (seller's 
regret). I use it mostly at the lathe, to blow out the pulley chamber, 
clean up the chuck and get shavings out of hollow forms in progress, 
etc. Also while occasionally cleaning up around the lathe, or dusting 
the interior of my unmentionable saws & Delta dust collector. Never seen 
another. Highly recommended. Photo on groups.io

FWIW

Don

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