GENERAL GEOLOGY 
33 
Both seemed — as seen from the ship — to be wholly vol¬ 
canic, but pebbles of crystalline rocks like those found on 
St. Lawrence Island, farther north, and on the Siberian 
mainland were found on the beach of St. Matthew, where 
they may possibly have been brought by the ice. 
We made landing on the northeastern side of St. Mat¬ 
thew near the north end, and afterward coasted along the 
a, b 
FIG, 6, CLIFF-SECTION, NORTHEAST SIDE OF ST. MATTHEW ISLAND. 
whole length of the island. We found it, as reported by 
Dr. Dawson, who touched at the southeast end and then 
coasted along the shore as we did, to be made up of bald, 
rounded hills, the residual portion of more extensive vol¬ 
canic accumulations of some antiquity, but without modern 
cinder cones (figs. 6 and 7). We landed at the prominent 
point forming the southern border of the broad bay that 
FIG. 7. CLIFF-SECTION, ST. MATTHEW ISLAND. 
Enlargement of ct-b in fig. 6. 
sets into the middle of the island (fig, 8). Dr. Dawson 
describes the same section as seen from his ship. 1 
As we coasted along the eastern shore of the island 
there could be seen, extending for a long distance to the 
south of the bluffs where we landed, a lower bed of dark 
lava with a quite smooth upper surface. Above this lay 
a very thick bed of a light-colored lava which seemed to 
be the same as the light trachytic rock which made up the 
, 1 Geological Notes on Bering Sea, etc., Bull. Geol. Soc. Am., vol. v, p. 136. 
1894. ' 
