Chdnyes of Level in the Bermuda Islands. — Tarr. 299 
accumulation resting upon the base rock and covered by the 
wind-blown sand (Figs. l-5j. In origin this beach is much 
later than the base rock ; for in it are found many pebbles 
wrested by the waves from the underlying strata, (Figs. 4 and 
5), and these are as hard and dense as the parent rock itself. 
Hence befoi'e the pebbles were removed by the waves the base 
rock had reached approximately its present state of consoli- 
dation. The pebble V^each here mentioned, also contains nu- 
merous shells of species that are now living, (Fig. 3). This 
unconformity, with all the features here described, may be 
seen with especial clearness at the point which forms the 
northern side of Devon bay on Main island. 
Accamalafion of the JEolian Beds. In the basal portion 
of the iBolian beds on the south shore there is usually a layer 
of 3'^ellowish and reddish coral (or shell) sand, whose color 
shows the extent of disintegration before covered by the up- 
per beds.* In places this lower discolored layer is absent; 
but at Devon bay, the typical locality here described, it rests 
upon the pebbly beach beds and hence indicates a certain pe- 
riod of disintegration before the sand wiiich foi-ms the hills 
began to encroach. 
This prove!? an elevation between the period of beach forma- 
tion and the accumulation of the teolian beds: for a soil dis- 
colored by disintegration, and containing numerous land shells 
exists upon a pebble beach containing sea shells. How great 
this elevation was, cannot be exactly stated; but it was cer- 
tainly not less than fifteen feet, for at this hight the sand 
hills rest on the pebble beach. It \^ probable that the uplift 
was sufficient to connect the various islands, and raise most 
of the surrounding shoals above the sea. An uplift of fifty 
or sixty feet would elevate almost the entire area above the 
present sea level. The reason for stating this supposed great- 
er elevation as a probahilify is, that there is evidence (stated 
below) that at one time during the history of the accumula- 
tion of the blown sand hills, the islands did actually attain this 
elevation. The uncertainty lies merely in the question whet- 
*The red and yellow stain is that of concentrated iron salts derived 
from the carbonate of lime during? exposure to the weather. This color 
is present in the residual soils of the Bermudas, and is also found fre- 
quently among the leolian layers, wherever the accuniulution of the sand 
was checked long enough to allow disintegration to produce this effect. 
