NEW RAILWAY-CUTTING AT GUILDFORD. 601 
the bulk of the lowest stratum, mixed with only a few angular or 
slightly worn flints, these last derived from the vicinity of the gorge, 
not having travelled sufficiently far to receive much abrasion. I 
have traced this lowest bed as far as the old chalk-quarry to the 
south, where on the top of the cliffit is distinctly seen, though now 
a mere remnant, resting on the Chalk, at the same level; and it is 
interesting to observe that the present line of drainage intervenes 
and separates this outlying portion. 
At about 100 yards eastward, the gravels and sands are seen in full 
force on both sides of the cutting (vide Main Section, fig. 8) and con- 
tinue for about 260 yards, up to15 miles 18 chains. These show that 
up to 14 feet, material referable to the Lower-Greensand hills towards 
the sources of the Wey still forms the principal part of the sands 
and gravels, which are coarse below, very fine at top, with no pebbles, 
and some, formed in rapid water, presenting false-bedding, and un- 
mistakably fluviatile (figs. 1 & 2, a—f). Above this level the beds (q), 
although here still horizontal, are far coarser, and are exclusively 
derived from the Chalk, marking a considerable change in the con- 
ditions of their formation and the area from which they have been 
derived. At their extreme limit eastward, the lower sands and 
gravels bend gradually over, and pass below the level of the railway 
line up to this, ascending 1 in 100; the lowest well-marked dark bed 
of gravel here, 64 feet above the Wey, or 164 above the sea, was 
followed in excavating the ballast for the line to 12 feet lower, at a 
point some 60 yards further east, and near the western end of the 
new railway-station. Where these sands fall over, the Tertiary clays 
also disappear; and it seems to me that the former owe their dis- 
placement, not to any depression such as a pot-hole in the chalk, but 
to their lying, and not improbabl¥ having been deposited originally, 
_ against a bank of the clay, which would have a natural tendency to 
slip, particularly if subjected to pressure from above ; water too would 
act upon the surface of the chalk and reduce its level, while it would 
not produce the same effect on the adjacent stiff clays. The strike 
of this displacement of the sands lies upon a line drawn thence to 
the reappearance of the clays beyond the three-arch bridge at Cross 
Lanes; and it is interesting to note that here, again, the superin- 
cumbent sands also showed aslight displacement from the horizontal, 
even a miniature fault of two or three inches being visible in the 
sands; and the dark gravel, but not so thick, was again met with, 
at five feet below the level of the line, as I am informed by 
Mr. Wills. 
It is not unlikely that the junction of the two formations, so 
unlike in composition and power of withstanding the effects of 
denudation as the Chalk and Tertiary clays, was a line of old 
drainage, a lateral tributary from the east previous to the deposition 
of the sands; there is some evidence of this under Watford Farm at 
their eastern limit, where they abut sharply against the clays. 
Before reaching the railway-bridge at the London road a very 
different set of beds has been cut into (wde sections, figs. 1g & 
2a’, b', and figs. 5 & 6), irregularly bedded, coarse, loamy sands, thick 
