Geological researches in China, Mongolia, and Japan, during the years 1862-1865.

CHINA, MONGOLIA, AND JAPAN. 79
CHAPTER IX,1
GEOLOGICAL ITINERARIES OF JOUTJNEYS IN THE ISLAND OP
YESSO, IN NORTHERN JAPAN.
THE following notes were taken during journeys made in the service of the
Japanese Government, in the summer and autumn of 1862. As the very small
population of this northern island is composed almost entirely of fishermen, it is
confined to small villages scattered along the sea-shore. The only roads are those
connecting these hamlets, with the exception of rare bridle-paths penetrating the
interior. The mountains west and north of Volcano bay are covered with dense
forests and a denser undergrowth of a kind of bamboo, so close-set that the country
is impenetrable, excepting by wading in the beds of torrents.
Thus the geologist is obliged to content himself chiefly with the sections exposed
on the sea-shore.
Hakodade, the seat of the Viceroyalty of Yesso and Krafto,2 is at the foot of a
peak about 1,150 feet high, connected with the main island by a low, sandy neck.
The rock that forms this island-like promontory is apparently a pluto-neptunian
product resulting from the metamorphism of trachytic tufas and conglomeratebreccias. Where I examined it, it consisted of a' fine-grained felspathic base,
containing1st. Felspar in oblong crystals, from very small to one-third of an inch in length.
These were white, highly fractured, and frequently showed triclinic cleavage.
2d. Quartz in pellucid grains, very irregularly distributed, in places absent, in
others equalling the felspar.
3d. Hornblende in small prisms.
4th. Magnetic iron in grains.
The rock in this locality has somewhat the appearance of having been broken up
and partially refused, but more generally it shows signs of stratification, and I have
referred it to the extensive marine deposit formed out of the debris of volcanic
rocks.3
On the northern slope of the peak is a terrace of recent gravels raised 100 feet
or more above the bay.
Between the hills of the main island and the sea there lies a plain the surface of
which slopes gently toward the water, where it terminates in places in high bluffs,
1 See Map, P1. 8. 2 Sagalin of the Russians.
3 This is probably the rock described in Corn. Perry's Japan Expedition, as granite with crystals
of turmaline.