14 GEOLOGY. 



they always are with magnetite ; their origin can be explained under 

 either hypothesis. W. T. 



Foster, Dr. C. Le N. Eemarks on the Lode at Wheal Mary Ann, 

 Menheniot. Trans. B. Oeol. Soc. Cornwall, vol. ix. pt. i. pp. 152- 

 157, 3 woodcuts. 



The lode traverses clay-slate or * killas,' running a few degrees E. of 

 N., and dipping E. 60*^ to 80°. Sections of the lode at various points 

 are given; and its history is inferred as follows: — 1. Eormation of 

 fissure and probable shifting of the strata ; 2. Deposition of the cah 

 (a sort of chalcedony), partly filling up the fissure, and cementing 

 fragments of the wall into a breccia ; 3. Reopening of the fissure, the 

 new line sometimes coinciding with the original wall, sometimes inter- 

 secting or running in the middle of the cah ; pieces of the walls and of 

 the previously formed cab-lode fell in, and then the other minerals were 

 deposited successively in the open spaces. There have been at least 

 two periods of the formation of fluor spar; the galena was deposited at 

 an intermediate period ; and the last minerals have been quartz, chaly- 

 bite, and calc spar. W. T. 



. Note on Belowda Hill Mine. Journ. R. Inst. Cornwall^ 



no. xvii. 1875, p. 213. 



Considers the so-called lode to be granite altered by solutions brought 

 up through the veins by which it is traversed. The felspar has been 

 replaced by schorl and tinstone. C. L. N. E. 



Gilbert, John. Notice of a Yugh in St. Ives Consols Mine. Trans. 



R. Oeol. Soc. Cornwall, vol. ix. pt. 1, pp. 158-160. 

 This vugh was a natural cavern in granite, 15 feet long, 12 wide, 

 10 high, lined with large crystals of quartz, and continuing with 

 smaller dimensions for more than 12 fathoms. It went off" at right 

 angles from a lode at a depth of about 190 fathoms from the surface. 



C. L. N. E. 



Glen, David C. Notes from the Island of Bute. I. On a Tract of 



Columnar Sandstone and a Perched Boulder, near Kilchattan. 



II. On a Magnetic Sand from East Bay, Rothesay. Trans. Geol. 



Soc. Glasg. vol. v. pt. i. pp. 154-159, 1 fig. in text. 



Notes of occurrence. 



Goodchild, J. G. The Glacial Phenomena of the Eden Yalley and 

 the Western part of the Yorkshire-Dale District. Quart. Journ. 

 Geol. Soc. vol. xxxi. pp. 55-99, pi. ii. (map) and 15 woodcuts. 



Describes the evidence for the ice-sheet and the distribution of 

 boulders. Glacial markings on Baugh Eell seem to indicate a height 

 of not less than 2300 feet for the upper surface of the ice-sheet. On 

 one side of a line shown on the map the ice moved southwards ; on the 

 other side it flowed northwards as far as the Eden Yalley, where, by 

 the blocking up of the lower part of the valley by ice from the N. W., 

 the local ice was turned up the valley over Stainmore towards the 

 North Sea, carrying with it all the boulders from E. of a line through 



