Were it my opinion that Symmes's Theory is one of the wildest and most ridiculous that ever entered into the brain of man, I would not refuse to hear him; nor by malevolent or satirical disapprobation, attempt to discourage him, before I had examined and reflected upon it. By the examination of many speculative subjects, abounding with falsehood, we are frequently enabled to treasure up some truths. Some of the first and most important discoveries in chemistry, owe their origin to the midnight vigils of the alchymists, who vainly sought for the philosopher's stone: and many valuable combinations in the science of mechanics have been discovered by those who wasted years in as vain a pursuit, after a perpetual motion.
I believe there are but few theories, which do not contain much that is profitable. The man who has the ingenuity to advance new ones, will be likely, in the course of reasoning necessary to support them, to say something that is useful to be known. In his very reveries and wanderings, he will often point out land-marks, which may be useful to the future _traveller_. Whether then is it better to crouch under the tyranny of prejudice, or employ our thoughts and reasoning powers in the search of truth, though at the risk of deceiving ourselves, as our predecessors have done? Had it not been for a prudent boldness in advancing and defending new doctrines, the human mind must have remained to this day, the sport of all the chimeras of the ancients.
The exact shape and formation of the earth are admitted not to be well understood. The laws of gravity, and the admeasurements which have been made in different places on the same meridian, have demonstrated to us, that the greatest mathematicians have mistaken its real figure. Various theories have at different times been published and refuted, and others substituted in their stead. Yet still a shade of darkness and mystery appears to hang over the subject; for many principles, attractions, and apparent variations from the established laws believed to exist in the economy of nature, have been discovered, particularly in the polar regions, which remain unexplained and unaccounted for. Let us, therefore, examine and investigate any theory which proposes to explain them. Let us not be so tenacious of our own opinions, and hereditary prejudices, as to stop at the very point where every thing invites us to proceed. Let us rather push our researches after knowledge to the utmost, and exercise our reason, and every means in our power that may tend to the advancement of science and knowledge. In the pursuit, let us not be retarded by the cry of prejudice, or the sarcastic whispers of the narrow minded, and selfish.