CONDUCTED BY E. L. AND W. J. YOUMANS.

The Popular Science Monthly was established a dozen years ago to bring before the general public the results of scientific thought on many large and important questions which could find no expression in the current periodicals. Scientific inquiry was penetrating many new fields, extending important knowledge, and profoundly affecting opinion upon numberless questions of speculative and practical interest. It was the policy of this magazine at the outset, and has been constantly adhered to since, to obtain the ablest statements from the most distinguished scientific men of all countries in their bearing upon the higher problems of investigation. Leaving the dry and technical details of science, which are of chief concern to specialists, to the journals devoted to them, The Popular Science Monthly has dealt with those more general and practical subjects which are of the greatest interest and importance to the people at large.

Science is the great agency of improvement in this age, private and public, individual, social, professional, and industrial. In its irresistible progress it touches everywhere, and affects everybody. It gives law to the material interests of the community, and modifies its ideas, opinions, and beliefs, so that all have an interest in being informed of its advancement. Those, therefore, who desire to know what is going on in the world of thought in these stirring times, when new knowledge is rapidly extending, and old errors are giving way, will find that they can keep informed only by subscribing for The Popular Science Monthly.

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