Dean Rosovsky likes to assume his department chairmen can count.

But apparently Ernest May, last year's History chairman, has lost his abacus: he allowed four tenured American History professors to take leaves this fall, leaving American History concentrators with three half-courses to choose from.

So this week Rosovsky decided it was time to give his students some guidelines; he sent a letter to Wallace MacCaffrey, this year's History chairman, announcing he would no longer approve individual requests for leaves until the chairman submitted a chart, outlining the department's leave patterns for each year.

Glen W. Bowersock '54, associate dean of undergraduate education, said yesterday the only real change in Rosovsky's leave policy is the dean's insistence that department chairman "personally assure" the Dean that undergraduate course offerings will not suffer from Faculty absences.

Rosovsky also came down this week on short-term Faculty absences, charging that professors increasingly have taken leaves of several weeks without soliciting his permission. The Faculty rules require professors to obtain approval from Rosovsky before leaving the University for longer than a week.

No statistical evidence is available to back up Rosovsky's charge, but Bowersock said he "shared the general impression" that the Faculty has taken a more "casual" attitude toward the leave rules.

Bowersock said professors most often take short-term leaves without permission during reading period.

"I would guess that you could hold a Harvard Faculty meeting in early January in the Caribbean," he admitted.

Bowersock paused to consider his statement, then added, "Then again I bet you could hold a Student Assembly meeting in January there, too."