Later, I learned that this machine was built by Bell Lab in New Jersey and used for gun tracking calculation on the Battleship Missouri, on which General MacArthur signed the unconditional surrender of Japan in September of 1945.
I also learned that this gun bombarded Hitachi-City (located about 150 miles north-east of Tokyo) in the spring of 1945, where Hitachi originated their business. This slow-time analog computer had to be used to aim the big guns on the Battleship Missouri.
At that time, I was at my home in Ina-City, Nagano-Prefecture, which is about the center of Japan main island, northwest of Mt. Fuji and about 150 miles from Tokyo. We could hear the roaring of the gun bombardments. All family members were huddled together and trembled with scare throughout a night.
Professor Akira Onishi of Soka University in Japan (also the creator
of FUJI socio-economic simulation model -- more later -- and Vice President
of ISAGA/Japan) told me his horrible experience of witnessing heavy casualties
(even those victims whose heads were blown away) in Hitachi-City, where
he was at that time.