On approach caused by vibration
Frederick Bickell Guthrie · Proceedings of the Royal Society of London · 1871
Abstract 1. The chain of experiments which I have to describe arose from the endeavour to explain an observation that a delicately suspended piece of cardboard moves, from a considerable distance, towards a vibrating tuning fork. It will be preferable to detail the experiments, not in the order in which they occurred to me and were actually performed, but in the order in which I conceive them to form a logical sequence.