The bottom stamp differs by having Niagara Falls, Ontario rather than Bradford, PA on it.
Zippos had a flat bottom until 1946 when the bottoms were indented.
From 1933 to the mid 50s the word Zippo was stamped in block letters. From August, 1949 through July, 2002 Zippos were also produced in Niagara Falls, Canada - the only place other than Bradford, PA where they were ever produced.
The Zippo script logo was developed in the late 40s and was phased-in on the lighter bottom stamp around 1955. About 13.5 million lighters were produced by Zippo Canada.
Slim lighters were first introduced in 1956, with a flat bottom and no date code.
The first markings were added in 1957 and overlapped into 1958.
His career was reborn in 1953 with the success of From Here to Eternity, with his performance subsequently winning an Academy Award and Golden Globe Award for Best Supporting Actor.Sinatra found success as a solo artist after he signed with Columbia Records in 1943, becoming the idol of the "bobby soxers".He released his debut album, The Voice of Frank Sinatra, in 1946.Sinatra released several critically lauded albums, including In the Wee Small Hours (1955), Songs for Swingin' Lovers!(1956), Come Fly with Me (1958), Only the Lonely (1958) and Nice 'n' Easy (1960).