A CELEBRATION observing the 80th birthday of Prof. Gerard DeGeer of Sweden will be held in Hanover October 1 and 2. Professor DeGeer is an eminent glacial geologist and the discoverer of the method of measuring varved clay. The week-end program will include demonstrations of DeGeer geological theories at certain esker and varved clay formations on the Connecticut River. Prof. James W. Goldthwait will serve as chairman of the discussion meetings and Richard J. Lougee '27 of Colby College is in charge of arrangements. A number of geological teachers from eastern institutions are expected to participate in the week-end program.