Japanese Navy Instrument ??

[Element7]

Hello Gents!
I need some help with this one. My Grandfather brought this home along with some other stuff from his Navy days during WWII and the Korean War. My father believes it was some type of instrument used on a Japanese Navy ship. It appears to be a large thermometer and it is full of mercury. It came with the storage case seen in the picture and a wall mounting bracket. I keep it stored on the wall mount because of the mercury. I think keeping it upright is the safest way to keep it. Other then the Japanese righting on the case the instrument is marked “K. Suzuki Iidamachi Tokyo No. 1730”. Your thoughts, comments, opinions and ideas regarding origin, use, storage and value would be appreciated.

Thanks

Kirby