82 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 58 



ENGLAND (Continued) 



468. . The mineralogical constitution of the finer material of the 



Bunter pebble-bed in the west of England. 



Quart. Journ. Geol. Soc. London, Vol. 58, 1902, London, p. 623. 



Paragraph on cassiterite " Difficult to distinguish from rutile, but it occurs in 

 small quantity in the heavy residues from some of these sands. Seem to be two 

 modes of occurrence: (I) in pale-yellow, well-shaped crystals, and (II) in more 

 or less rounded brownish grains." 



469. THOMAS, JOSIAH. Description of the operations at Dolcoath mine. 



Journ. Roy. Inst. Cornwall, Vol. 3, No. 11, 1870, Truro, pp. 191-197. 



An account of the mine, and manner of working it. Author states that at time of 

 writing he believes " we are working to a greater depth, and raising a larger 

 quantity of tin, as well as making greater profits, than any other tin mine in 

 the world. 



" The mine has been producing of late about 87 tons of black tin per month, or 

 1060 tons per year." 



470. . Description of Dolcoath main lode, illustrated by transverse 



section, and specimens from the lode and country. 



Rep. Proc. Min. Ass. Cornwall and Devon, for 1882 (1883), Truro, pp. 13-15. 



Dolcoath is the deepest metalliferous mine in Cornwall. The granite has become 

 softer, and the tin lodes larger and more productive with depth; mine shows no 

 sign of decay. 



471. THOMAS, R. Report on a survey of the mining district of Cornwall, 



from Chasewater to Camborne. 



1819, London. I 



Not available- to the authors. 



472. THOMAS, R. A. Notes on Cornish mines in 1896. 



64th Ann. Rep. Roy. Cornwall Polyt. Soc., 1896, Falmouth, pp. 89-94. 



Discussion of the decreased tin output of Cornwall, and of means for its increase. 



THOMAS, R. ABTHUB. See No. 1666. 



473. THOMAS, RICHARD A. Some observations on the " Great Flat Lode " in 



Wheal Uny mine, near Redruth. 



64th Ann. Rep. Roy. Cornwall Polyt. Soc., 1886, Falmouth, pp. 184-188. 1500 

 words. 



Calls Great Flat Lode a " true fissure vein," but says it reaches 72 feet 

 (12 fathoms) in width with a small amount of tin distributed evenly through it. 

 Dip varies. Slickensides occur where vein narrows. Many " cross-courses " break 

 up the vein. Generally dips to the west. Occasionally rich enough to work 30 

 feet wide. Copper ores in upper part of vein and some chalcopyrite below. 



474. THOMAS, WM. Excursion to Cornwall. 



Proc. Geol. Ass,, Vol. 10, 1887, London, pp. 196-215, figs. 7. 



Mentions a few general points about Carclaze, Cam Brea and other tin mines. 



475. THOMAS, WM., and BURROWS, J. C. 'Mongst mines and miners, under- 



ground scenes by flashlight. 



1883, London and Camborne, pp. 32, pis. 26. Colored section of Dolcoath main lode, 

 62% fathoms per inch. 

 Written in popular style. The plates are excellent. See 467. 



476. TREDINNICK, R. Tin and tin mining. 



Mg. Journ. Railw. Comm. Gaz., Vol. 46, 1876, London, p. 1388. 



General article giving amount of ore raised and profits derived from some of the 

 Cornwall mines. 



