Thomson, a publisher of two legal encyclopedias, sued American Lawbook alleging that they infringed on Thomson’s copyrights. The court asked: is a copyrighted law book infringed by a subsequent work on the same subject where the only accusation against the second author is that he collected all available citations, including those found in the copyrighted work, and, after examining them in text-books and reports, used those which he considered applicable to support his own original text? The court found in the negative, finding that if it was held that an author could not consult the authorities collected by his predecessors, the law of copyright, enacted to promote the progress of science and useful arts, would retard that progress