Got a spare dollar or two, a Sunday for leisure, and a yearning for blue skies and salty ocean breezes? Then you would probably be interested in the Martha's Vineyard-Nantucket inexpensive summer Sunday cruises.

A train leaves South Station Sunday morning at 8 o'clock and returns twelve hours later. This train ride takes you 72 miles down through the historical south shore of Massachusetts past Plymouth, across the Cape Cod Canal at Buzzards Bay, and finally to Woods Hole on the southern neck of the Cape, jutting out into Vineyard Sound.

When you hear the conductor swinging down the aisle chanting in that peculiar manner reserved for train conductors, Woodsole! Woodsole!," you will know that it is time to change from train coach to cool, windswept steamer deck is certainly a refreshing one, calculated to make you quickly forget about those unloved physics problems or the mad conclusion of Harvard Square.

The trip from Woods Hole across the sound to Oak Bluffs on the Vineyard takes roughly three-quarters of an hour. From Oak Bluffs you can branch out to any part of historical Martha's Vineyard. You will have five hours or so before the steamer returns from Nantucket. A bus runs over to Edgartown on the southern end of the island, and to Vineyard Haven and West Chop. You can also cross to the extreme corner of the island to the Indian Reservation at Gay Head. A chat with boat builder Manuel Swartz, whose shop is only a stone's throw from the Edgartown Yacht Club, is worth the price of the whole excursion.

The trip to Nantucket, 30 miles father out in the Atlantic, costs considerably more and eats up the extra hours that could be spent touring the vineyard. But for the salt-water cruise addict the longer ocean trip is well worth while. Nantucket, like the Vineyard, has escaped the commercialization which has ruined so many other vacation resorts. Here you will find gray-shingled cottages covered with rambler roses, cobble stoned streets, and century-old houses with "widder's walks," where Nantucket wives once climbed to look for the return of the old whaling ships.

Whether you choose the Vineyard or Nantucket cruise, the trip will be a Sunday well spent, and will offer a relaxing break in a strenuous week of study.