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READ: Principles of Geology

Excerpts from Charles Lyell, Principles of Geology

"Sir Charles Lyell, 1st Bt" by John & Charles Watkins. Licensed under Public domain via Wikimedia Commons
Charles Lyell (1797 — 1875) was a Scottish lawyer and the foremost geologist of his day. He is best known as the author of Principles of Geology. It popularized geologist James Hutton’s concept of “uniformitarianism” — the idea that the Earth was shaped by slow-moving forces still in operation today. Uniformitarian ideas opposed the common belief among many geologists that unique catastrophes or supernatural events, like the biblical flood in the story of Noah, shaped Earth’s surface. The motto of uniformitarianism was “the present is the key to the past.” Lyell’s friend, Charles Darwin, took that idea and extended it to biology.
In fact, Lyell’s Principles of Geology was one of the few books that Darwin carried on his famous voyage on the HMS Beagle — a voyage that led him to write The Origin of the Species. What follows is a summarized version of the original text.
Geology defined — Compared to History — Its relation to other Physical Sciences  Geology is the science which investigates the successive changes that have taken place in the organic and inorganic kingdoms of nature. It inquires into the causes of these changes. And it describes the influence which they have exerted in modifying the surface and external structure of our planet.  
By this research into the state of the Earth and its inhabitants at former periods, we acquire a more perfect knowledge of its present condition. Our views concerning the laws governing its animate and inanimate productions become more comprehensive. When we study history, we obtain a more profound insight into human nature. We can draw comparisons between the present and former states of society. We trace the long series of events which have gradually led to the current state of affairs.  
By connecting effects with their causes, we are enabled to classify and retain in the memory a multitude of complicated relations — the various peculiarities of national character. More deeply can we understand the different degrees of moral and intellectual refinement, and numerous other circumstances. Without historical associations, these would be uninteresting or imperfectly understood. The present condition of nations is the result of many previous changes. Some are extremely remote, and others recent, some gradual, others sudden and violent. In a similar way, the state of the natural world is the result of a long succession of events. If we seek to enlarge our experience of the present inner workings of nature, we must investigate the effects of her operations in past eras.  
On looking back into the history of nations, we often discover with surprise how the outcome of some battle has influenced the fate of millions today. This remote event may be connected to the current geo- graphical boundaries of a great state, the language now spoken by the inhabitants, their peculiar manners, laws, and religious opinions. But far more astonishing and unexpected are the connections brought to light when we dig deeper into the history of nature. The form of a coast, the layout of the interior of a country, the existence and extent of lakes, valleys, and mountains, can often be traced to earthquakes and volcanoes in regions which are now tranquil. These ancient upheavals are the reason why some lands are fertile, and others are sterile. They determine the elevation of land above the sea, the climate, and various peculiarities.  
On the other hand, much of the Earth’s surface was formed by slow operations such as the gradual depositing of sediment in a lake or in the ocean, or to a great increase of testacea and corals.  
To select another example, we find in certain areas underground deposits of coal, consisting of vegetable matter which drifted into what were formerly seas and lakes. These seas and lakes have since been filled up. The lands the forests once grew upon have disappeared or changed their form, the rivers and currents which floated the vegetable masses can no longer be traced. And the plants belonged to species which have passed away from the surface of our planet ages ago. Yet the wealth and numerical strength of a nation may now be mainly dependent on the distribution of fuel determined by that ancient state of things.  
Geology is closely related to almost all the physical sciences, as history is to the moral. A 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. Likewise, 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 brought to them by former events. They would know what combination of causes similar effects were relatable to. And they would often be abled to infer information concerning many events unrecorded in the archives of former ages.  
But since no one individual can be expert in so many subjects, it is necessary that men who have devoted their lives to different departments should unite their efforts. The historian receives assistance from experts on ancient times and from scholars of moral and political science. In the same way, the geologist should avail himself of the aid of many naturalists. He should particularly gain the help of those who have studied the fossil remains of lost species of animals and plants.  
To be fair, we can only compare one class of historical monuments to the records studied in geology — those which unintentionally mark past events. The canoes, for example, and stone hatchets found in our peat bogs, inform us about the arts and manners of the earliest inhabitants.

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