The primary purpose of this paragraph is to paint a picture of the ocean as the boys experienced it. It was cold but sunny, the surf and waves were active and large, the wind was blowing in off the sea. Finny took it all in, deeply experiencing the sights and sounds and smells and sensations of sand and water and salt. Finny also did his best to insure that Gene shared in the exhiliration and joy of the outing.
Finny may have recognized that Gene was not initially thrilled with the idea of this trip, taking place the night before a major exam and breaking all Devon School rules. However, Finny treasured Gene's friendship and was willing to put out significant effort to insure that Gene was enjoying himself. Finny realized how much he needed Gene's companionship, even as Gene struggled to define his constantly changing feelings about Finny.