If my addition is correct, readers have located 6 rare Stewart handcrank heaters in the US & UK. They are rare enough that the antique Road Show people couldn’t get any information about them from their buyers (see the 2nd to last post on this page).
Dennis, who’s heater is featured here, decided to fire up his heater at night, creating this cool picture. He also sent an unrelated artsy pic of an M37 he thought he’d share. Thanks!