46 APPENDIX. 



The latitudes have all been observed by myself, chiefly from meridional altitudes of 

 the sun, v^hen available, and when not, from observations of the stars, taken with a good 

 sextant, by the method of reflection ; the longitudes are from a large map of my own 

 survey. 



With regard to the geological map, having previously surveyed a great portion of 

 the tract, I may, with some confidence affirm, that the topographical features are accurate, 

 and so also are the outline delineations of trap and sand-stone; the lias required a more 

 minute survey than my time afforded ; the outline of its extent is correct enough, but the 

 sand-st07ie collines, which protrude through it are, in a great measure, conjectural ; and the 

 primitive strata are comprised under one distinctive coloui", as it would have required minia- 

 ture minuteness to have delineated them, under separate heads ; the strata of Beragerh, for 

 instance, comprise a series from gneiss to dolomite in a space of two miles, and a delineation 

 of them would have represented a ribband, with all the colours of the rambow, rather than 

 a geological arrangement, in a map of so small a scale. 



III. 



