From the main highway the delta built by West Fork Brook into glacial Lake Hadley appears as a flat terrace along the western highland (18.2). The rolling fields (19.7) east of the railroad are dunes which were once raised by the wind along the old Connecticut channel. Mill River, which rises near Conway, parallels the highway for 6.1 miles and crosses it here to enter the Connecticut (20.3). The road approaches the massive gray rocks of the western upland (20.5), and the Hatfield lead vein (see p. 64) outcrops in a bluff on the right (20.9). The view south (22.3) shows the water gap between the Mount Holyoke and Mount Tom ranges. At the State Police barracks (23.4) the Hatfield road turns left, and a short distance beyond (23.9), on the west side of the road, is the abandoned City Quarry. The granite exposed in the quarry contains a black, radio-active mineral called allanite, and each glistening black crystal is surrounded by a reddish halo caused by bombardment of the feldspar by alpha particles. A road to Florence branches right (24.5) near the railroad crossing, and one to the Coolidge Bridge turns left across the Boston & Maine tracks (24.7). A by-pass to the Berkshire Trail (25.6) goes west, and the tour returns to the Court House corner (26.1). _Northampton, Cummington, Plainfield, and South Deerfield_ This tour includes a representative section of the Connecticut Lowland, traverses rugged valleys on the western margin of the lowland, and crosses a wide remnant of the New England upland. The trip is 58.6 miles long, and all of it except the last twelve miles moves through rapidly changing scenery. The route leaves the Court House corner on State Highway 9, the Berkshire Trail, following Main and Elm Streets past Smith College. At the Cooley Dickinson Hospital the road rises from the bed of glacial Lake Hadley to the Mill River delta, which, despite some dissection, maintains the same general level through Florence (2.6) to Look Park (3.4), where a ridge dotted with glacial erratics rises through it. The road follows the delta margin past the Veteran’s Hospital and shortly (4.3) climbs to the land of erratics and stone fences. The road from Whately (see p. 88) enters from the right in Haydenville (7.1), and the Trail continues up Mill River to Williamsburg (8.1). Not far beyond the center of Williamsburg the road forks left for Chesterfield and right for Cummington.