1866. | Hints to Home Tourists. 853 
a period of transition between the exploded superstitions of our 
ancestors and that wide diffusion of science in the popular mind 
which, we are led to believe, will mark the ages of the future. In 
the meanwhile, such words as “volcanic,” “cataclysms,” “ up- 
heayals,” “convulsions,” and a good many more, are commonly used, 
and sometimes even by scientific people, in a vague, misty sense, to 
account for phenomena which have arrested the attention, but of 
which no satisfactory explanation has occurred. And so the change 
from the devil and the witches has not always been very much for 
the better; for, in truth, most of the present outlines of the surface 
of the country may just about as legitimately be ascribed to the 
agency of evil spirits as to that of volcanoes. 
When we set ourselves seriously to study the matter, we soon 
learn, perhaps to our surprise, how small is the proportion which 
the number of really volcanic hills bears to the whole long list of 
hills in this country. One of the first results of such a study is to 
shake our faith in the truth of the common impression that present 
ruggedness of surface has some necessary connection with former 
volcanic eruptions, or that evidence of these eruptions is to be 
sought for only where the ground is rough and broken. But this 
impression is so deeply rooted, that it requires no small effort, and 
not a little acquaintance with facts as they are in nature, before it 
can be finally cast aside. But cast aside it must be, if we would 
make any satisfactory progress in physical geology. In no single 
instance in the British Islands does any hill, formed of rocks of 
voleanic origin, present still its original outlines. Probably its 
existence as a hell is an event long subsequent to the eruption of its 
component rocks, and due to a very different cause. Owing to 
many ups and downs, dislocations, and repeated prolonged wearing 
away, only a remnant of the erupted material is now to be seen. 
Hence all our so-called “craters” are deceptive, and take their rise 
from the unequal erosion of the rocks among which they le. In 
like manner the conical outline so often assumed in this country by 
truly volcanic rocks, arises wholly from the way in which they yield 
to the wasting influences of nature. The most rugged parts of the 
British Islands are not volcanic, while some of the most remarkable 
traces of ancient volcanoes are to be found among corn-fields and 
gardens, and even under the streets of villages and towns. It is 
only after a careful study of the structure of the rocks that we at 
last discover that it is to denudation, or the unequal wearing away 
of the surface of the land, and not to movements from below, that 
the details of the present configuration of our country are mainly due. 
The subject of the present paper is one which, I am well aware, 
cannot be satisfactorily discussed without ample space and an 
abundance of illustrations. My object, however, is not to discuss 
it, but rather to point out its nature, in the hope that some readers 
