Geology is intimately related to almost all the physical sciences, as
history is to the moral. An historian should, if possible, be at once
profoundly acquainted with ethics, politics, jurisprudence, the military
art, theology; in a word, with all branches of knowledge by which any
insight into human affairs, or into the moral and intellectual nature of
man, can be obtained. It would be no less desirable that a geologist
should be well versed in chemistry, natural philosophy, mineralogy,
zoology, comparative anatomy, botany; in short, in every science
relating to organic and inorganic nature. With these accomplishments,
the historian and geologist would rarely fail to draw correct and
philosophical conclusions from the various monuments transmitted to them
of former occurrences. They would know to what combination of causes
analogous effects were referable, and they would often be enabled to
supply, by inference, information concerning many events unrecorded in
the defective archives of former ages. But as such extensive
acquisitions are scarcely within the reach of any individual, it is
necessary that men who have devoted their lives to different departments
should unite their efforts; and as the historian receives assistance
from the antiquary, and from those who have cultivated different
branches of moral and political science, so the geologist should avail
himself of the aid of many naturalists, and particularly of those who
have studied the fossil remains of lost species of animals and plants.

The analogy, however, of the monuments consulted in geology, and those
available in history, extends no farther than to one class of historical
monuments--those which may be said to be _undesignedly_ commemorative of
former events. The canoes, for example, and stone hatchets found in our
peat bogs, afford an insight into the rude arts and manners of the
earliest inhabitants of our island; the buried coin fixes the date of
the reign of some Roman emperor; the ancient encampment indicates the
districts once occupied by invading armies, and the former method of
constructing military defences; the Egyptian mummies throw light on the
art of embalming, the rites of sepulture, or the average stature of the
human race in ancient Egypt. This class of memorials yields to no other
in authenticity, but it constitutes a small part only of the resources
on which the historian relies, whereas in geology it forms the only kind
of evidence