GEOLOGICAL SECTIONS. 



51 



TABLE OF DIP, DEPTH, AND THICKNESS continued. 



Not-. Messrs. Troughton and Simms, of Fleet Street, London, prepared (at 

 the suggestion of the late Mr. Jukes) a little ivory protractor (p 9) 011 which 

 portions of similar Tables to the above are engraved, together with the scales^of 

 the six-inch and one-inch maps, and which the observer will find very useful "to 

 have in his note-book or map-case. Its price is 10s. 



42 



