iv 



APPENDIX. 



5. One of the most advantageous situations for obtaining specimens, and examining the rela- 

 tions of rocks, is in the sections afforded by cliffs on the sea shore ; especially after recent falls of 

 large masses. It commonly happens that the beds thus exposed are more or less inclined ; and in 

 this case, if any of them be inaccessible at a particular point, the decline of the strata will frequently 

 enable the collector to supply himself with the specimens he wishes for, within a short distance. 

 Thus, in the subjoined sketch, which may be supposed to represent a cliff" of considerable height, — 

 the observer being situated at a, the beds b, c, d, though inaccessible at that place, may be examined 

 with ease and security, where they successively come down to the shore at 6', d, and d'. 



6. To examine the interior of an unknown country, more skill and practice are required : 

 the rocks being generally concealed by the soil, accumulations of sand, gravel, &c., and by the 

 vegetation of the surface. But the strata are commonly disclosed in the sides of ravines, — in 

 the beds of rivers and mountain-streams ; and these, especially where they cross the direction 

 of the strata, may be made, by careful examination, to afford instructive sections. 



7. Among the occasional components of the strata, the remains of organized bodies, — -shells, 

 corals, and other zoophytes, — the bones and teeth of animals, — fossile wood, and the impressions of 

 vegetable stems, roots, or leaves, &c., are of the greatest importance ; aff'ording generally the most 

 marked characters of the beds in which they occur. — These should, therefore, be particularly sought 

 after, and their relative abundance or rarity in different situations noticed. The petrified bodies 

 should, if possible, be kept united with portions of the rock or matrix in which they are found ; and 

 where they are numerous, — in sand, clay, or any moist or friable matrix, — it is in general better to 

 retain a large portion of the whole mass, to be examined afterwards, than to attempt their separation 

 at the time of collecting, 



8. The loose materials which are found above the solid rocks, in the form of gravel, silt, rolled 

 pebbles, &c., should be carefully distinguished from the solid strata upon which they rest. And the 

 more ancient of these loose materials, found on the sides or summits of hills, &c., should be distin- 

 guished from the recent mud, sand, and gravel, brought down by land-floods, or by rivers. The 

 bones and teeth of animals are not unfrequently found in the more ancient gravel ; and the col- 

 lection of these remains from distant quarters of the globe, is an object of the greatest interest to 

 geology. 



9. Besides a note of the locality, there ought, if possible, to accompany every specimen, a short 

 notice of its geological circumstances ; as — 



Whether it be found in large shapeless masses, or in strata ? 



