2 Comments Posted by Industrialist

Its a 60's era eureka roto matic canister, 60 inches of vacuum pressure is actually what this machine will pull if you put a gauge to it.. My only guess is they switched it on and off to achieve negative/positive vacuum pressure.
Upon scearching the web...its apparently the entrence to the kitcehen...the design signifies the deviding line for boys and girls holding out bowls for food...with the center person being the cook...hope this helps