80 GEOLOGICAL RESEA 11 CUES IN 



in others in low terrace steps. Near Kameta this terrace is covered Avith a few feet 

 of clayey sand, underneath which is a bed of whitish clay used for fine tiles ; more 

 generally these terraces are a bluish, sandy clay, rich in recent shells, and fringing 

 the less precipitous shores of most of the Japanese islands. 



First Excursion. May 24th, 1862. — Leaving Hakodade we crossed to the main 

 island by the low neck of land. This is formed by a bar of stiff clay, perhaps of 

 the same age as the terrace deposit, which lies a few feet above high-water, and is 

 covered with drift sand. Along the eastern edge of the neck, the sand has been 

 raised by the winds into hills, sixty to eighty feet high, the shapes of which change 

 with every storm, excepting where protected by a suificient growth of wild rose- 

 bushes. Behind these hills the ground is SAvampy, the Avater finding a very sIoav 

 draina2:e throuofh the sand. 



FiE. 9 



1. Loam. 2. Marsh. 3. Drift sand. 4. Stiff clay. 



Following the beach of the northern shore of the bay for several miles, Ave 

 turned off at a small village, and, ascending a creek, entered the fertile valley of 

 Ono, a broad marshy plain on Avhich are some of the principal farms of the island. 

 An inferior rice and silk are said to be among the chief products. 



May 25th. — Branching off from the main road, a foAV miles beyond the village 

 of Ono, and folloAving a mountain brook, Ave reached the lead mines of Ichinowatari. 



These mines lie at the entrance to a small valley, on the sides of which the out- 

 cropping rocks, containing the veins, are black and gray argillites, slightly calcare- 

 ous, and highly metamorphosed, in alternating beds; the gray rock being apparently 

 the younger. These are associated Avith greenstone, Avhether eruptive or meta- 

 morphic was not ascertained, AA'hich occupies most of the valley to its head. On 

 the summit of the ridge the greenstone was found by Mr. Blake to be succeeded 

 by a shale, from which he took a calamite, and this again by the black rock already 

 mentioned. 



The veins occur in all of the aboA^e rocks; the predominating veinstone being 

 of magnesite bearing, in nodules, threads, and impregnations, black and yellow 

 zinc-blende, iron pyrites, galena, and, in places, copper pyrites. The AvaU rocks are 

 highly impregnated with small cubes of iron pyrites. 



In Japan, as in China, the Avant of pumping machinery prevents Avorking to any 

 considerable depth below the adit level. The galleries in this mine Avere tolerably 

 well timbered, but low a,nd narroAv. From ignorance of the use of poAvder in 

 blasting, their means of attacking the rock Avere — till the application of poAvder in 

 mining Avas introduced by us — confined to the use of pointed instruments, a miner's 

 pick with one point, similar to our own, a hammer and gad Avith handle, like the 

 German Eisen, completing the outfit. The ore is roughly assorted by hand, and 

 then passed under dry stamps. I Avas not a little surprised to find, in the moun- 

 tains of Japan, stamps constructed on the same principle as our OAvn, though the 

 workmanship and efficiency are far inferior. 



