Cataract Tool and Optical Co., Manufacturer of Telescopic Rifle Sights and Mountings. Illustrated advertising design in black & light green showing Rifle with Telescopic Sight on 1901 cover franked with 1901 2¢ Pan-Am (trivial flaws) tied by "Buffalo, N.Y." machine cancel, wonderful matching illustrated letterhead included showing Rifles with Scope, a Lathe & a Telescope, plus imprinted in red at bottom, as invitation to the visit their exhibit at the Pan-American Exposition, Very Fine, a rare item. Estimate  $100 - 150. $0 (Image)