Page:Popular Science Monthly Volume 51.djvu/131

medal for his steam hammer, Mr. Nasmyth was given a complimentary notice for the lunar pictures—and to the Queen and Prince Consort personally. In the course of his astronomical observations he turned to consider the causes of the sun's light and other phenomena of light and heat. In May, 1851, he sent a communication to the Astronomical Society embodying his views that the light of the sun was simply the result of an action on that body of ethereal matter distributed through space unevenly, so that its intensity would vary as the system passed through different regions; that variability in stars might be thus accounted for; and that our Glacial period was produced by the solar system passing through a region deficient in power of luminosity. Mr. Nasmyth found afterward that these views were paralleled in some features of the theory of the sun enunciated by Dr. Siemens in 1882. He delivered a lecture on the Structure of the Lunar Surfaces before the Edinburgh Philosophical Society in 1858, and in 1874 brought out his book on The Moon considered as a Planet, a World, and a Satellite—a work which at once made its mark in selenological literature. He busied himself also with the study of the spots on the sun, and made the novel discovery of the willow-leaved structure of the solar surface, which attracted universal attention among astronomers. Sir John Herschel complimented him upon it in his Outlines of Astronomy; the astronomers at Greenwich made observations that confirmed it; and Father Secchi was trying to illustrate it by sprinkling rice grains over a blackboard covered with glue at the very moment Nasmyth was introduced to him by their fellow-astronomer Otto von Struve. We should mention, too, in connection with his astronomical studies the paper which he presented to the Royal Astronomical Society about 1851 on the Rotatory Movements of Celestial Bodies, which was suggested by the motion of that kind acquired by water running out of the bottom of a basin. Mr. Nasmyth was also interested in microscopy, and studied twenty-seven forms of infusoria in the water of the Bridgewater Canal; in photography, and made models of parts of the moon's surface and photographed them; in the origin of the form of the Pyramids, which he attributed to the appearance of the sun's rays streaming through clouds; and to the derivation of the cuneiform characters from the shapes of the impressions made by striking soft clay with the corner of a parallelogram-shaped instrument. He wrote Remarks on Tools and Machinery in Baker's Elements of Mechanics (1858).