The SF&SJ "Pacific" and the Central Pacific "Pacific" are two completely different locomotives. My books are still boxed from my move, so I can't check further, except to confirm that the CP "Pacific" (#2, completed in Sept 1863 then shipped around the Horn) was a Mason, and that SF&SJ only ordered one Mason, #11 "Menlo Park", in 1870. These are based on xerox copies of the Mason order sheets for the respective locomotives.
Kyle K. Wyatt
Curator of History & Technology
California State Railroad Museum
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