To observe the total eclipse of the sun for the island of Sumatra on January 14, 1926, Professor H. T. Stetson, assistant Professor of Astronomy, will leave Cambridge tomorrow for San Francisco, from where he will sail for Sumatra on November 7, with three associates.

Weld Arnold '17 and W. A. Spurr '25, will accompany Professor Stetson from Harvard, and will be joined by Mr. W. W. Coblentz of the United States Bureau of Standards. The Party will make a study of the heat radiation of the Solar Corona, which is the same type of work as done by Professor Stetson and Mr, Coblentz in Connecticut last January, when they determined the heat of the Corona at 3000 degrees.

Equipment Already Shipped

Approximately one and a half tons for equipment, including a 20-inch reflecting telescope, loaned by the college observatory, along with radio-metric and photometric instruments were shipped from Boston about the first part of this month, and will have arrived in Sumatra by the time the observers land there on December 30.

Dr. Stetson' party will be one of three to observe the occurrence of this natural phenomenon. Of the other expeditions, one will be from Swarthmore College and the one from the Naval Observatory.

Professor Stetson plans to return by way of the Mediterranean and Europe, and will arrive in Cambridge early in March. During his absence, Professor S. D. Townley of Leland Stanford University will take over Professor Stetson's work at the University.