

274 STRUCTURAL AND FIELD GEOLOGY 
said to have had much preliminary training in either 
mineralogy, petrography, or paleontology. 
The best method of getting a grasp of structural or 
tectonic geology is to attempt the construction of a geological 
map from one’s own observations. There are few more 
engrossing or interesting pursuits than that of unravelling 
geological structure, and the investigator will find that the 
labour involved is amply repaid. For not only does he gain 
a precise and intimate knowledge of the country surveyed, 
but he learns to appreciate geological processes and their 
results as he cannot do in any other way. His conceptions 
of what is meant by denudation and the origin of surface 
features; of crustal disturbances large and small; of the 
metamorphism of rocks, and a thousand other questions will 
be broad and assured, or narrow and uncertain, according as 
his knowledge has been derived at first hand from his own 
personal observation or at second hand from books. 
Our first attempts at mapping will likely enough be 
halting and unsatisfactory, but with zeal and patient endeavour, 
experience and success will follow. After having devoted 
due attention to the subject, we may expect in fimewie 
acquire such facility in reading and interpreting the stony 
record, that only one or two, rapid traverses of a region may 
suffice in many cases to disclose to us its geological structure, 
Indeed, the mere configuration of the ground will often 
reveal to a trained observer the leading geological features 
of a country, and enable him to produce a reliable sketch- 
map. Experts, however, are not infallible, and in rapidly 
traversing a region may miss important evidence which could 
not have escaped them had the ground been carefully 
surveyed, 
Field Equipment.—The apparatus required in geological 
mapping is fortunately neither elaborate nor heavy. There 
are field-geologists who in some way or other manage to 
conceal about them all that is essential for the purpose. 
Others, again, are so elaborately accoutred as to attract the 
attention of every passer-by. The only necessary apparatus, 
however, consists of the following :—a hammer, a pocket-lens, 
a compass and clinometer, a note-book, a stylographic pen, a 
common lead-pencil, and a good, reliable topographical map. 
