Thimble Peak, approximately 10,000 ft. First ascent, August 11. E. Cromwell, P. Kaufmann. From camp at head of Bugaboo Creek, via Bugaboo glacier and south arm, to col between Thimble and Howser Peak. Ascended east ridge to summit. Descended west ridge to col between Thimble and Flat Top. Ascent, 4 hours, 20 minutes. Descent, 20 minutes.