Motion pictures were taken of the waves produced by the Ivy Mike shot. They were taken over shallow water inside the lagoon near some of the islands of the atoll. Records were obtained at Elmer and Yvonne which give arrival times corresponding to an average wave velocity of about 80 ftsec. The general character of the waves was a long slow rise followed by a long negative phase during which several smaller oscillations were observed. The complete wave train was not observed. The indicated product of wave amplitude highest to lowest water times the horizontal distance from zero was 4.5 x 10 to the 5th power sq ft. Since this value was increased by shoaling, the deep-water amplitude was somewhat less, and the product is estimated as 2.7 x 10 to the 5th power sq ft. The results are in agreement with theory, including the predictions of George N. White on the upper limit for the Mike water-wave amplitudes.