U.S. Patent No. 836,466

A 3D model of U.S. Pat. No. 836,466. Cutting edge 1906 self-measuring bottle technology from the original database of things--the U.S. PTO.

And the '221 Patent isn't the first patent on this idea. Take a look at U.S. Pat. No. 236,997 for prior art!

More available here!