In the world of ninety foot shells all eyes will be glued on a twisty-dirty river in the heart of Philadelphia where the three giants of eastern rowing. Navy, the University of Pennsylvania, and Harvard meet this Saturday afternoon for the Adams Cup Regatta.

At stake will be Navy's string of 23 consecutive victories and Harvard's chance to avenge its narrow loss to the Middies exactly a year ago this coming afternoon.

Also at stake will be the ambition of Pennsylvania coach Joe Burk to beat his predecessor, Navy coach Rusty Callow who was the Red and Blue varsity coach before he moved to Annapolis and launched his fabulous middies on their world-beating career.

Just how good the three crews will be on the rubbish-filled Schuylkill River is a matter for Saturday to answer. Meanwhile, a little background on the three boats is in order.

First, the title holders and acknowledged champions:

Navy, called by some the "three year invincibles" and by others the roulette combination that always wins, is the same crew, except for two men, which won the 1952 Olympics. Last season this eight went undefeated and was seriously challenged only once, by Harvard, in the Eastern Sprints at Washington, D.C. This season the Middie eight hasn't lost a race and last Saturday set a two mile record over calm Onondada Lake. In terms of a mile and three-quarter race, the time would be near 8:48.'

This crew is experienced, powerful, and has precision timing. It is to be noted that Navy's only narrow squeak came from Harvard when the current was strong and the water choppy. The Schuylkill River is an unpredictable river which may give trouble.

And next the challengers:

Penn averages close to 190 pounds and is stroked by former Canadian sculls champion Jack Guest. The eight skimmed by all opposition in its two races this season, setting a course record for the Childs Cup on Lake Carnegie. The time was 8:59.1 with a strong quartering wind. This clocking compares with Harvard's record-setting race last Saturday when the varsity finished the same course in 3:49.5, nearly ten seconds lower.

In early season comments, Penn's coach criticized his crew's timing. "We are a big crew," said Burke, "but Penn is not a 21-Jewel piece of precision mechanism." He might also have pointed out that his eight is one of the strongest rowing this season.

And as for Harvard: another big crew, close to 190, with two lettermen and a new record to its credit, plus fancy time trials on a wind-swept Charles. The local eight has not lost in two starts and has shown an ability to handle rough water.

More than actual rowing prowess, the Crimson eight is spurred on by recalling last year's race, when it licked Navy's heels, a feat that has not been done before or after, at least not up to this Saturday's meeting.