388 Scientific Intelligence. [May, 



The same principle may be applied in various other forms ; 

 e. o-. one of two polished metallic plates might be furrowed 

 with intersecting lines. The plates might then be applied to 

 each other, and their edges soldered or cemented together, ex- 

 cept at two points, one for the entrance and another for the exit 

 of the gas. These plates, thus applied, would form a part of the 

 passage between the lamp and gasometer. This too is capable 

 of augmentation at pleasure. Both this and the tube with wires 

 might be easily surrounded, when in use, with cooling or freezing 

 mixtures. By such means the powerful aid of the gas blow-pipe 

 may be obtained with a great degree of safety. 



III. Geological Description of Hut ton's Island.* 



This island is situated near the western coast of Corea, 36° 

 10' north latitude, and 126° 13' east longitude. The N.E. end 

 is composed of a fine-grained granite, the middle of the island 

 of a brittle micaceous schistus of a deep blue colour, the strata 

 are nearly horizontal, but dip a little to the S.W. This body of 

 strata is cut across by a granite dyke, at some places 40 feet 

 wide, at others not above 10 ; the strata in the vicinity of the 

 dyke are broken and bent in a remarkable manner ; this disloca- 

 tion and distortion do not extend far from the walls of the dyke; 

 but veins of granite branch out from it at a great distance, vary- 

 ing in width from three feet to the hundredth part of an inch ; 

 the dyke is visible from the top of the cliff to the water's edge, 

 but does not reappear on the corresponding cliff of an island 

 opposite to it, though distant only 30 yards. This island is 

 composed of the same schistus, and is cut in a vertical direction 

 by a whin dyke, four feet wide, the planes of whose sides lie 

 N.E. and S.W. being at right angles to those of the great granite 

 dyke in the neighbourhood, which run S.E. and N.W. The 

 strata contiguous to the whin dyke are a good deal twisted and 

 broken, but not in the same degree as at their contact with the 

 granite dyke. 



The whin dyke is formed of five layers or sets of prisms laid 

 across in the usual way. Beyond the small island cut by the 

 whin dyke, at the distance of only 40 or 50 feet, we came to an 

 island rising abruptly out of the sea, and presenting a high, rugged 

 cliff of breccia, fronting that on which the granite dyke is so 

 conspicuous : the junction of this rock with the schistus cut by 

 the granite and the whin, would have been interesting; but 

 although we must have been at times within a few yards of it, 

 the actual contact was every where hid by the sea. 



The whole of the S.W. end of this island is formed of breccia, 

 being an assemblage of angular and water-worn pieces of schis- 

 tus, quartz, and some other rocks, the whole having the appear- 

 ance of a great shingle beach. The fragments of the schistus 



» Extracted from Capt. Hall's " Account of a Voyage of Discovery to the 

 West Coast of Corea, and the great Loo-choo Island." 



