Science: Watertight

In Boston one day last week officials of Provident Institution for Savings watched the 30-ton door of their bank vault ponderously close and lock. A motor compressor forced air into the vault through a ventilator until a pressure-gauge climbed to 4 Ib. per square inch over atmospheric pressure. At that level the gauge stood still nearly an hour after the air input had stopped. A valve was then opened and the compressed air wheezed out.

First of its kind that anyone knew of, the test showed the vault airtight, hence watertight. With safety-deposit boxes only six inches from the floor, the bank's...

Want the full story?

Subscribe Now


Learn more about the benefits of being a TIME subscriber

If you are already a subscriber sign up — registration is free!