Page:Popular Science Monthly Volume 19.djvu/532

516 last decade is Neison's "Moon," the accompanying chart in sections giving the principal features of the planet's surface. Nasmyth and Carpenter's "Moon," illustrated by fine photographs of prominent insulated peaks, mountain-ranges, and crateriform mountains, and Proctor's "Motions, Aspect, Scenery, and Physical Condition of the Moon," furnish delightful and instructive text to the general reader.

Very beautiful drawings of single craters, viewed under high power, have been made by Secchi, Nasmyth, and Carpenter. Bertch, Arnauld, Temple, and Harriot, a young English astronomer, have given us topographical lunar drawings of considerable merit.

The greatest change in lunar illustration occurred in the application of the telescope to photography. The moon, sighted by a telescope provided with a meniscus lens for the collection of the actinic rays, and kept in the field by the driving-clock, casts her image on a sensitive plate, which, being developed, gives all the numerous details of the lunar surface dimly and minutely, to be sure, but capable of enlargement and printing to apparent life-size.

Draper photographed the moon in 1840; Bond, in 1850; De La Rue and Rutherfurd, in 1857, the former discovering that the pictures could be combined in the stereoscope so as to appear globular. Photographic representations of the moon, in her various phases, are eminently picturesque, though lacking distinct detail; they are, however, correct, for, granted that the apparatus is properly adjusted, the sun paints with perfect truth.

Neison's maps of the moon were first done in water-color. Some have also been done in this vehicle by the "Moon Committee" of the Royal Astronomical Society of London." It has been reserved for Henry Harrison, a young American astronomer and artist, to paint the first and only true telescopic portrait of the moon in oil-colors.

"Not difficult to do!" exclaims the uninitiated observer.

"Impossible!" returns the scientist. "No one can paint the moon in detail."

Nevertheless, our æsthetic astronomer set to work to paint the six phases, which would give a portrait not only picturesque, but so true to details and coloring that it could be offered to the scrutiny of eyes long practiced in the nightly study of the orb itself—eyes that would be quick to detect the absence of the smallest crater, the presence of a superfluous peak.

After the professional duties of the day, Mr. Harrison, when the weather was propitious, passed his time in making observations of the heavens. Seated at the telescope, he would pass hour after hour, studying the surface of the lunar orb.

On one of these occasions, a summer evening, singularly calm and clear, his wife joined him. Sitting for some time completely absorbed in the brilliant spectacle, she at last exclaimed: "Henry, paint that, if you can; it is beautiful beyond description!"