I managed to find one of these and bought it at the fair I have been attending all week. Unfortunately the wire closure system has been removed, and a number of other post-war modifications have been made to the box. I wonder if someone could perhaps send me detailed photographs of the closure, or perhaps the Patent Number for the design. Please send images via PM, e-mail or post them on here. My sincere thanks in advance.
I am also delighted to tell everyone that these items are indeed World War 2 issue, and were used in hospitals. The ones that are shown on this site are small cabinets, and there was also a large cabinet produced too. These were mounted on a large trolley chassis, with two small ones being mounted on the chassis. Here are the official designations for the items, according to the Medical Supply Catalog - March, 1944:
7230005 - Cart, Food, Drinkwater, with One Large Cabinet, Complete:
Consists of chassis, platform and food cabinet with cans.
7230010 - Cart, Food, Drinkwater, with Two Small Cabinets, Complete:
Consists of chassis, platform and food cabinets with cans.
7231000- Cart, Food, Drinkwater, Cabinet, Food, Large:
Without cans. Four of 7235000 and two of 7236000 ordinarily used with this cabinet.
7232000 - Cart, Food, Drinkwater, Cabinet, Food, Small:
Without cans. Three of 7233000 and two of 7234000 ordinarily used with this cabinet.
7233000 - Cart, Food, Drinkwater, Can, Type A:
6.5-qt. For use with 7232000.
7234000 - Cart, Food, Drinkwater, Can, Type B:
7.5-qt. For use with 7232000.
7235000- Cart, Food, Drinkwater, Can, Type C:
10.3-qt. For use with 7231000.
7236000 - Cart, Food, Drinkwater, Can, Type D:
18.9-qt. For use with 7231000.
I hope that helps identify this mystery item, and any help with sorting out the closing mechanism for my example really would be appreciated.