Photos of congresses 1924 meeting in Delft: The participants of the First International Congress for Applied Mechanics, held in Delft in 1924. In the front row J.M. Burgers, C.B. Biezeno,and L. Prandtl. (image provided by Prof. F. T. M. Nieuwstadt) 1934 meeting in Cambridge, U.K.: The participants of the Fourth International Congress for Applied Mechanics, held in Cambridge, U.K. in 1934 (image provided by Prof. H.K. Moffatt). 1938 meeting in Boston, U.S.A.: The participants of the first International Congress on Theoretical and Applied Mechanics to be held in the United States was the Fifth Congress, held in September 1938 at Harvard University and the Massachusetts Institute of Technology, Cambridge, Mass (image provided by Prof. J.W. Phillips). 1948 meeting in London, U.K.: The participants of the Seventh International Congress on Theoretical and Applied Mechanics, held in London in 1948. (image provided by Prof. H. K. Moffatt).