1878.] 
Superficial Gravels and Clays 
321 
The Middle Glacial Gravels here and throughout the 
Finchley district: contain a considerable proportion of rounded 
pebbles from the Eocene beds. 
Farther down the slope, in the field on the north side of 
Oldershill Lodge, the gravel has been largely worked. The 
following important section (Fig. 7) was exposed when I visited 
the pits in J anuary last. The gravels extend to within about 
40 feet of the level of the Brent, or Dollis Brook, as the 
stream is here named. 
The upper clay A, 1, is here nearly without stones, excepting 
patches near the surface. It very closely resembles the 
Upper Brick-clay of the Thames Valley, and, as it is un- 
doubtedly a continuation of the Upper Boulder-clay, and 
overlies the Middle Glacial Sands and Gravels, this change 
Fi£. 7. 
Gravel-pit in Field near Oldershill Lodge. 
s. Surface soil. A, I. Brown unstratified clay, with vertical joints. A few nests of 
pebbles at surface. Angular patch of gravel at x . a, 2. Coarse gravel in 
sandy clay. A, 3. Dark, sandy, laminated clay. c. Sand and small sandy 
subangular gravel. 
to the usual form of the brick-clay, as it descends into the 
valley, is very significant. In this sedition there was an 
angular piece of reddish sandy gravel, lying completely sur- 
rounded by the clay, at the point marked x in Fig. 7. 
Descending Hendon Lane there are more old gravel- and 
sand-pits, in which exadtly the same succession of beds is 
shown as in Fig. 7. These extend down to the line of 
200 feet above the ordnance datum. Below this the ground 
slopes more rapidly towards the brook, and the middle sands 
and gravels thin out, but the Upper Clay, with its gravel 
patches at base, overlaps the Middle Sands and Gravels, and 
continues down to the bank of the brook, where it is seen 
as shown in Fig. 8. 
Crossing now to the Hendon side of the stream, the sur- 
face deposits are shown in a large brick-field on the south 
VOL. viii. (n.s.) y 
