248 Lead Mines, &c. of Hampshire County, Mass: 
a aan and increase in size and number, as we draw near 
o the protrusion of rocks. Brooks and streams have fre- 
quot cut through the tertiary, down to the tock formation, 
carrying the sand and earth down the stream, but leaving the 
rounded masses behind: Bes . 
pon excavating the earth, these rounded masses are often 
found in great abundance, quite down to the rock formation, 
though they are sonietimes confined at and near the surface. 
When the rounded masses are found as in the first descrip- 
tion, the earth is generally that kind which is called ‘ hard- 
pan,” it being indeed extremely hard. When the masses are 
only near the surface, sand usually lies next the “way nec 
tion. This sand, under a magnifier, appears to be com- 
posed principally of minute particles of quartz, sa small 
mica; the sand is frequently in layers, and some- 
times conta?ns scales of mica an inch or two in diameter. 
Next 6: the sand is a layer of gravel, which appears 
full of sm arnets, precisely the same in Sapte as 
those ieee in the mica and taicose slate of this region. *Ma- 
ny of them have all their sides perfect, although genshiily the 
angles seem to be rounded off by attrition; the gravel often 
grows coarser as it approaches the stratum which lies upon it. 
This stratum consists of rounded masses of rock, of all sizes, 
mixed with gravel and earth, as in the profile below. 
Among the rounded masses may be found fragments of all 
the rocks of this region, viz. of granite, taleose and mica 
slates ; sienite, greenstone, horablende and micaceous lime- 
stone. unded masses of quartz are also seen, sometimes 
y coarser particles of gravel also seem 
Mone be chiefly of” the above named rocks, and appear to 
have | n peeces to their present size by attrition. The 
est place for viewing this latter description: of geest, is three- 
: ‘ths of eee of the meeting-house in Williamsburgh. 
' Thave seen the same appearances at — on the plain 
