I. GEOLOGY. 823 



The matrix is Doleritic, the imbedded fragments are Fossiliferous Lime- 

 stone, probably of Carboniferous age. 



Figs. 13 and 14. Magnetite crystals in Felstone, x 350. Near Downhead, 

 Mendips. 



9a. Mechanical Autotype of Plate 9, by Messrs. Vincent Brooks, Day, and 

 Son. . . 



b. MAPS, DIAGRAMS, &c. 



COLLECTION OF MAPS AND SECTIONS LENT BY 

 THE GEOLOGICAL SURVEY OF THE UNITED 

 KINGDOM OF GEEAT BRITAIN AND IRELAND. 



3258a. Geological Map of the Keswick District, on the 



scale of 6 inches to the mile, with appended one-inch maps, 

 sections, &c. J. Clifton Ward. 



With this are exhibited three one-inch maps of the same district, one of 

 which serves as a coloured index sheet to the large map, and shows the varied 

 dips of the strata, while the other two serve as cleavage and glacial maps. 

 Also a horizontal section at the foot of the large map on the six inch scale, 

 ten horizontal sections on the one-inch scale, a section through the plumbago 

 mine in Borrowdale, and twenty-four chromo-lithographic figures of the 

 microscopic structure of rocks of the district. 



3253aa. William Smith's original Geological Map 



of Hackness Hill, Yorkshire, being one of the earliest geological 

 maps ever constructed on a large scale. R. Turnbull. 



The maps of William Smith " the Father of English Geology " of the out- 

 lying mass of the Middle Oolite at Hackness, exhibit in a striking manner 

 the great knowledge of their author and the able manner in which he traced 

 and mapped their geological structure, and also pointed out its bearing on the 

 agriculture of the district. The geological survey map of the same area, while 

 it helps to form a comparison of the old and new style of mapping, at the same 

 time shows that William Smith was well acquainted with the general details 

 of this unique and somewhat obscure group of rocks. 



Series of Views in the Cam Valley, near Bath, 



coloured geologically. This was the valley in which William 

 Smith, the father of English geology, made his earliest discoveries. 



W. Stephen Mitchell, LL.B. 



3253ab. Geological Survey Map of the same district for 

 comparing the old and new style of geological surveying. 



R. Turnbull. 



3253b. One-inch quarter-sheet, 101 S.E. of the Ord- 

 nance Survey (Keswick District), converted into a Model 

 by Mr. Jordan, and this into a Geological Model by the exhibitor, 

 snowing the various geological divisions, dips, faults, and mineral 

 veins. J. Clifton Ward. 



The work here embodied is the result of the labours of the contributor as 

 an officer of the Geological Survey, but the colouring of the model has been 

 privately undertaken with a view to its presentation to the Keswick Museum 

 of Local Natural History. 



