US Maritime Ship's Barometer?

Description

I believe this is a US Maritime Ship Barometer, measured in inches of Mercury. It measures 5 1/2 inches across the face of the dial and about 7 inches across the whole front. Has some markings on the back (see photo). Please ask all questions before bidding. Please see photos. Winning  bidder to pay .00 shipping in US only. Check my feedback, bid with confidence!