32 
Mr. W. Pengelly on the Red Sandstones^ 
Dawlish ; the last locality furnishes numerous and probably the most 
striking examples in the district. An extremely fine case occurs on 
the South Devon Railway, in the cliff between the two tunnels next 
south of Dawlish. 
There can be no doubt that ''false stratification " was caused by the 
action of water moving with slight velocity in the direction in which 
the stratula^< (false strata) dip, and which transported the materials 
having the arrangement in question. The probable mode of 
operation may be thus illustrated : Suppose a party of navvies 
employed to extend the road a. (fig. 3) over the low ground b. 
They wheel out the ballast in their barrows and throw it over the 
scarp a., the slope which the talus will assume will depend 
principally on the force with which the material is shot out, and 
on the specific gravity and form of the fragments. The inclination 
will be small or great according as the force is great or small, and 
according as the materials are light or heavy ; angular fragments, 
when not merely plates such as slate fragments, will be more 
favourable to a steep talus than those having a rounded form. 
Other conditions no doubt belong to the problem, but those noticed 
are sufiicient for our purpose. When completed, a longitudinal 
vertical section through the road would disclose false stratification 
(the successive taluses), and would indicate not merely the direction 
of transportation, but, the materials being the same, would show, 
by the variations in the inclination, the changes in the strength 
everted by the workmen. The upper surface of the completed 
embankment would form a true plane of stratification, and on this 
another such bed might be built which would display the same 
phenomenon if built in the same manner, and the dip of the 
stratula would be in the same or the opposite direction as in the 
bed below according as the labourers worked from a. to b., as in the 
first case, or the reverse. 
Now, if for the " force of the navvies," we substitute the 
transporting power of running water," we convert our illustration 
into the veritable process by which diagonal stratification was 
produced, and on applying the principle to fig. 2 — the Slapton case 
— v/e learn that the bed d. was formed of fine sand transported in the 
direction b. a., whilst the stratum e. was built of similar material 
which travelled from a. towards b. ; the direction of the water-flow 
hawg changed before the commencement of the upper bed. 
The history of the section at Goodrington Sands (fig. is more 
involved, but, if I interpret the appearances correctly, a bed of 
sand, of which b. c, f. is a relic, had been deposited by water 
flowing towards N. 70® W. (mag.), and which threw down stratula 
inclined to the plane of the horizon at an angle of 81°=21*' (dip 
* This convenient term was, I believed, first used by Mr. H. C. Sorby. 
