persistent. On calm days, the boundary between salt water from the ocean and fresh water from the river is plainly visible at the surface as a line across which a subtle but distinct change in water color takes place. Sometimes even a change in the character of wind ripples is noticeable across the line.

The drowned valleys and tidal rivers of Connecticut once were filled with anadromous fish returning to their inland spawning grounds. Anadromous fish, such as striped bass, Atlantic salmon, and American shad, live their adult lives in salt water but are born and return to spawn in fresh water. At one time these fish were important sources of food for native Americans and early colonists, but construction of dams and pollution of waterways have blocked the return route to most of their former spawning grounds, drastically reducing the populations.

Atlantic salmon, considered by many to be the best-tasting fish in the North Atlantic, has been the hardest hit. Before the 19th century, the annual salmon run was a time of much excitement. Fishermen laid out nets and spectators lined shores beside waterfalls to watch the salmon's dramatic leaps. The biggest runs in the New World were up the Connecticut River. But with the construction of a dam at Turner's Falls, Massachusetts in 1794 and several more dams in the succeeding years, the salmon runs soon dwindled away to nothing. Happily, an intensive effort under way since 1967 to restore the fish to the Connecticut River basin is finally showing some success. Stocking programs and the construction of fish ladders around the many obstructing dams are inducing more and more fish to return. Hope is growing that eventually the great salmon runs will be renewed.

Glaciation is partly responsible for another fundamental feature of Connecticut's Coast: Long Island Sound. An understanding of glaciation's role requires a short explanation of how glaciers operate. A glacier can be thought of as a kind of semisolid river of ice flowing forward as new ice is added to it in the form of snow. The amount of area covered by a glacier depends on a balance between ice flowing forward and climate melting it back. Thus, even when the front of a glacier is

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