404 
[Assembly 
Brought forward, 
lower portion contains some fossil shells, the first seen 
in the section, the upper strata being destitute of any 
fossils except fucoides, 100 
4. Sandstone in two courses, variable in thickness, quarried at 
a bridge above Bannister's grindstone quarry, and used for 
aqueduct stones, j. 3 
3. Frequent alternations of tliin layers of sandstone with green 
shale, fossiliferous, 40 
2. Green shale, with numerous fossils, shells, and fucoides, ... 70 
1 . A mass consisting principally of green shale, with occasion- 
al very thin layers of sandstone. Few fossils in the 
lower part of the bed, Not accurately measured, proba- 
bly more than 100 
447i 
The fossils of the green shale are a few thin shelled Pterinea, Orthis 
and Delthyris, and a striated species of fucoid is constantly present, both 
in the shale and the layers of sandstone. In the upper part of this 
section, there is another species of fucoid, vertical to the strata, pre- 
senting in the numerous and closely arranged stems, a slight resem- 
blance to a syringapora. 
The surface of No. 10 has the appearance of a muddy sand, after 
the evaporation of a shallow pool of water ; the surface presenting lit- 
tle irregular depressions, divided by angular ridges. I have also no- 
ticed a similar appearance, though not to so great extent, in some of the 
other sandstones. 
Nearly all the sandstones of the above section, when of sufficient 
thickness, are fit for building stone. The upper stratum, No. 17, is the 
most purely siliceous, and consequently the most durable. No, 4 con- 
sists of two courses, one of them two feet thick, easily quarried and 
dressed ; and used in large quantities on the canal. No. 8 contains se- 
veral courses of variable thickness ; it affords a good material for grind- 
stones, for which it is quarried on the land of Mr. Bannister. I did not 
learn the amount annually taken from this quarry, but judging from the 
numerous and distant points where the " Rushford grindstones" are 
sold, it is greater than any other in the district. The stones are drawn 
to a mill on the stream near the quarry, and after being roughly rounded 
are placed in a lathe and turned smooth. 
