To the Editors of the CRIMSON:

I am informed that a writer in the CRIMSON has charged me with locking the doors of my classroom against late comers. This I have never once done in my thirty-five years of teaching. Your contributor may have gained his impression from the fact that last year, with a course of 600 students, I had the assistants refuse admission to those who appeared later than seven minutes after the hour. I assume, however, that even your writer would not regard this action as unreasonable in the case of a nine o'clock class. In any event, the action involved no possible violation of the fire regulations. Arthur M. Schlesinger,   Francis Lee Higginson   Professor of History.