I'd like to cancel a cheque www.fedhealth.co.za register It was my scientific hero Robert Hooke, the society's curator of experiments - the person in charge of those experiments recorded in 1661 - who made an important early contribution to explaining this strange phenomenon, based on the differential cooling of the glass itself after it was plunged into water, and drawing an analogy with the way the locked stones in brick arches collapse instantaneously and violently once the keystone is removed.