284 Mr. T. Sopwith, on Isometrical Projection. 



These, and the other sections introduced in this plan, suffice to show 

 that whenever it is desirable to combine several geological Sections in one 

 drawing, this mode of projection affords the means of doing so. The escarp- 

 ment and surface of rocks may be represented so as to show the connection 

 of the several beds or strata of which they are composed. Outlines of the 

 surface of a mountainous district may be represented in various directions, 

 and coloured so as to denote the basset of different strata. Isometrical 

 Projections may be made either from given measurements or from ordinary 

 plans and sections, by a process much more simple and easy than the rules 

 of common perspective. It approaches more nearly than any other mode 

 of drawing to the clearness of a model. 



The collection of information respecting the strata and subterranean 

 phenomena of the great mining fields of the north of England is an especial 

 object of this Society, and is of great importance in a district so dependent 

 as this is on subterranean sources of wealth. Next to the collection of such 

 details, their arrangement in such a form as may be generally useful, claims 

 attention ; and, in many instances, the simple and comprehensive mode of 

 Isometrical Projection may be employed with considerable effect, and pre- 

 sent the details of geological structure, combined with the attractions of a 

 picture. 



