Knowledge of the ether is expected to be greatly increased by the radio division of the Ak-Bulak eclipse expedition jointly sponsored by Harvard and M. I. T. that will sail on April 8 for Siberia to observe the phenomena which will be total on Friday, June 19.

Desiring to observe the ionosphere both as a function of time and of frequency, the expedition will take two sets of transmitters with which they hope to gain the desired information. Two 500 watt transmitters, designed to work on four specially assigned frequencies, are equipped to photographically record the ionosphere layer as a function of time, while a variable frequency transmitter, which goes from eight to two megacycles, is also equipped to take pictures of the layer but as a function of frequency.

Members of the Cruft Laboratory who are making the trip are Paul B. King, Jr., John H. Pierce '32, Harner Selvidge '34, and Edward P. York.