Twenty-nine members and seven visitors attended our AGM in January. After running through the business of the evening our Chairman, headed a lively presentation aided by two Committee members. The first demonstration was Prince Rupert's Drops which was performed under controlled conditions. The drops are made from toughened glass beads, created by dipping molten glass into cold water, which results in the glass solidifying into a tadpole shaped droplet. The outer layer of the glass shrinks as it cools and the molecules inside have nowhere to shrink to as the outer layer is already set hard. The body of the tadpole was hammered with no effect but breaking the tail caused the entire tadpole to shatter. This is not one to be tried at home.
The next demonstration was followed by Hooke’s Law of Springs using a carefully prepared apparatus. Weights were used to measure the stretch and force of the spring. Careful measurements were taken to show the accuracy of the experiment.
Both experiments were presented by Robert Hooke to the Royal Society during his time as Curator of Experiments.