CD 728.4 [020] Brookfield threadless embossed with the Cauvet patent for the internal screw thread.

Embossed: (F-Crown) (Arc) W. BROOKFIELD / 1 / 55 FULTON ST / N. Y. (R-Crown) (Arc) CAUVET'S / PAT. / JULY 25, 1865 {MLOD}.

The interesting thing about this one other than the patent anomaly is that this the more narrow dome version I associate with later