THE TERRACES OF THE GOSNECTIOUT. 729 



sheltered grooves described above in connection witli the "muck sand.'' In 

 digging wells in the lower part of Northampton along i\Iaple street, on tiie 

 north side of Mill River, and near the road leading to Hockanuni Ferry 

 from Pleasant sti'eet, the deposit has been found K! t<i "JO feet below the 

 river — a tine, bluish loam, with leaves, branches, and roots, buttenuits, but- 

 tonballs, hemlock knots, and a ])iece of coal. The same deposit was exposed 

 at the foot of King street in Northam])ton. 



Loess. — The most important stratum whicli goes to make up the ter- 

 races is the wholly unstratified loess whicli everywhere caps them. It is 

 most important economically as giving the meadows their fertilitv, and 

 deserves attention as a true water-formed river loess. Except for the lack 

 of any large per cent of calcic carbonate, which, as there is almost no lime- 

 stone in the drainage area of the Connecticut, is not surprising, and for the 

 resultant rarit}- of land shells in the bed, its agreement with the Rhine loess 

 is complete. It caps the river sands, and up and down the river presents 

 a cornice, often 8 feet thick, of a fine, dark, Avholl)^ unstratified loam, 

 pierced full of vertical root holes and breaking witli vertical walls. It is 

 the accumulated silt of the annual floods of the nver, each layer being 

 worked over by wind and frost and by the boring of worms and roots 

 until the whole becomes entirely massive ; and a rudely columnar structure 

 is produced by the multitude of root holes, which become jjassages for 

 water after the rotting of the roots, and so lessen the cohesion in this direc- 

 tion that a vertical cleavage results. This loess laj^er appears capping the 

 sm-face in the section (fig. 48, p. 737). It is finely shown in the curving 

 bank above Northampton bridge, where the rWev is wearing- with g-reat 

 rajjidity into the Hadley Meadow and is forming alreadv a great semicircle. 

 Here the loess forms a perpendicular wall below which the sand slope is 

 cut into great steps by the river as it sinks from high water, so that the 

 whole resembles a Roman circus. The loess is here 5 f^et thick. Over the 

 Hatfield lower meadow it is 6 feet thick; over the upper meadow about 2i 

 feet. Over the Northfield Meadows the loess is 6 to 8 feet thick, and is 

 especially strongly developed in the West Northfield Meadows. 



THE TERRACES OF THE CONNECTICUT IN TIIE SPRINGFIEIjD BASIN. 



The fact that the basin was left by the ice so nearly filled up to the 

 level of the later lake, and the fact that the contributions to the lake were 

 almost wholly from the east side, caused the thread of the cun-ent throuo-h 



