Stephen Prokofievitch Timoshenko 685 vibrations of beams to take account of the effects of rotatory inertia and shear. This short paper inspired many further investigations by others and was responsible for the term "Timoshenko beam'so often seen in the literature today. In the spring of 1922,Timoshenko received an offer of a job with the Vibration Specialty Company in Philadelphia and decided to try his fortune in America.He arrived in Philadelphia on 22 June 1922,and soon decided that America held great professional opportunity for him. THE AMERICAN YEARS Westinghouse Research Laboratory After a year with the Vibration Specialty Company,Timoshenko received an offer from the Westinghouse Company in Pittsburgh to join their research group in mechanics.One of his first projects was the development of photo- elastic equipment for the study of stress distributions.This simple apparatus was very successful and made a great impression on the research director, S.M.Kintner.It also showed that although Timoshenko preferred theoretical work,he had great talent for experimental work whenever he chose to exercise it. Another incident involved some work that he did with a new pendulum hardness tester that the company had recently purchased.A description of the device had appeared in a journal in which the inventor gave no explanation as to why it worked.Timoshenko became interested in the instrument and wrote a short paper presenting the theory behind its performance. It was not long before Timoshenko was acting as a consultant to engineers in other departments of the company.It was in this way that he met such men as L.S.Jacobsen,C.R.Soderberg,R.E.Peterson,J.P.Den Hartog,J. Ormondroyd and others with whom he worked closely in future years.Also among his colleagues was J.M.Lessells,with whom he wrote his first American textbook,Applied elasticity. One important Westinghouse project was an exhaustive theoretical and experimental study of stresses in rails.At that time,the Pennsylvania Railroad was being electrified and there were few empirical data available to guide the design of electric locomotives.Timoshenko headed a group of engineers who studied this problem at great length.Some of the results were presented by him to the 1926 International Congress of Applied Mechanics in Zurich. It was at the Westinghouse Research Laboratories that Timoshenko began his teaching career in America.A group of young company engineers,with whom he dealt in his capacity as plant consultant,asked him to teach them something about the theory of elasticity.Since there was no time during the day it meant giving lectures in the evening after a hasty meal,but the time was given willingly and the lectures were eventually replaced by a seminar which continued all the time he was at Westinghouse.It was here that he got some feeling for the kind of background that students graduated from American universities could be expected to have.He tells that he was appalled at the meagreness of their training,and this undoubtedly strengthened his resolve to resume his teaching career