Very early and rare Nunn brass oiler for early stationary gasoline or steam engine. Measures roughly 6 1/2" x 3"Has "Nunn Mfg Roch, NY" on rim of the oiler lidHas "No 35" and "Pat. Feb" , "5 - 89" on the bottom of the oilerLid has a cover with nice solid handle that rotates to open two fill holes on open sides of the oiler lidOiler has a very unusual and neat mechanism for adjusting the valve-stem. The top rotates and the lower end of the top has a series of notches wi...th numbers. A vertically moving spring-actuated catch, which is seated within a chamber formed in the bottom of the oiler cover, engages the notches and thus indicates the positioning of the valve stem as the top is rotated. This design was patented by Charels H. Nunn on Feb 5, 1889. A copy of these patent papers is included with the oiler. Overall, excellent original condition with very nice patina. Some wrench marks. A very early and rare oiler!