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Now as to the practical application of the foregoing observations. In the first place, it will be seen that such deposits of brick-earth as are made in this manner cannot be very thick, their total thickness perhaps, resting on the bottom of the valley, not being more than 20 feet, and it is frequently much less. The next thing to be noticed is that they must be very variable in character, a bed changing perhaps every 100 feet or so horizontally, and more often every few feet. Individual beds must of necessity be very irregularly developed under the circumstances. The velocity of the stream being greater at certain seasons of the year than at others, we frequently find some such section as the following developed:—

Fig.2.—Section of Fluviatile Brick-earth.

a = Mould and soil, of no use to the brickmaker.

b = Sandy clay, with a large proportion of sand; useful for moulding or incorporating with the “fat” clays below for brickmaking.

c = Gravel bed, lenticularly developed; suitable for mending roads, paths, &c.