NEW HAVEN, Conn.--Eastern League champion Princeton, on the strength of an incredible 40 point diving performance, moved into the lead at the end of the first day's competition at the Eastern Seaboard Championships. Harvard is presently in fifth place.

The Tigers, taking first or second in every race except the 50-yard free, amassed a first-day total of 108 points. Yale was second with 83, followed by Penn with 66, Dartmouth with 60 and Harvard with 48.

The first event, the 500-yard freestyle, proved to be the Crimson's best of the evening. Harvard's Rich Baughman and Fred Mitchell, who had qualified for the finals with their best times of the season, took second and fourth respectively.

Baughman, who has been getting stronger and faster as the season has progressed, was beaten by Princeton's Curtis Haydon, who set a meet record.

Nevertheless, Baughman established a new Harvard record of 4:42.581 in the event, eclipsing Mitchell's record of 4:44.153 set in the preliminary heat.

The two-four performance lifted Harvard into the lead after one event, but that lead soon changed hands as the Tigers began to pull away.

Dave Brumwell, swimming in the consolation 200-yard individual medley, took a ninth place, but swam a fast 1:59.628 to break yet another Harvard record. Charlie Campbell of Princeton took first in the final with a new meet record time of 1:56.525.

In the 50-yard freestyle final. Tim Neville, who gained the finals through a swim-off for the sixth and final spot, took a third despite one of his patented slow starts. This time a 21.448 tied the Harvard record held by last year's Crimson captain Mike Cahalan.

Harvard took its final points of the evening in the consolation finals of the 400-yard medly relay taking ninth.

First in the race, and seven place points eluded the Crimson when captain Paul Horvitz, swimming the freestyle leg, missed a turn after it appeared that a Crimson first was wrapped up. Harvard's first-day total of 48 points virtually equalled last year's three-day total of 49.5.