Once again the annual Cryogenic Engineering Conference has been held in Boulder, Colorado, and has been hosted by the University of Colorado's College of Engineering and the National Bureau of Standards Boulder Laboratories. In presenting the papers of this ninth national conference, the 1963 Cryogenic Engineering Conference expresses its thanks to these two hosts for the fine cooperation that has existed between these organ i- zations with regard to both cryogenic research and conference activity. Since the Cryogenic Engineering Conference was first initiated in Boulder in 1954 by R. B. Scott, present Manager of the NBS Boulder Laboratories, it is only fitting that this volume of the Advances in Cryogenic Engineering be dedicated to hirn. The 1963 Cryogenic Engineering Conference Committee also gratefully acknow- ledges the assistance of an Editorial Committee both in selecting papers for the program and in carefully reviewing the final papers for this volume. Participants in this thankless task inc1uded R. W. Arnett, V. D. Arp, P. L. Barrick, D. A. Burgeson, D. B. Chelton, R. S. Collier, J. W. Dean, T. M. Flynn, R. N. Herring, M. J. Hiza, J. Hord, J. G. Hust, V. J. Johnson, F. Kreith, R. H. Kropschot, P. R. Ludtke, D. B. Mann, R. D. McCarty, L. MuHen, M. T. Norton, R. P. Reed, R. F. Robbins, W. G. Steward, R. B. Stewart, D. H. Weitzel, and W. A. Wilson.