Page:Popular Science Monthly Volume 17.djvu/718

700, among naturalists as well as amateurs, regarding the proper means of preserving them. He has, accordingly, given a clear and concise account of the art, the implements used, and the principles upon which the work should be done. The subjects considered are, the skinning, preparing, and mounting of quadrupeds, birds, reptiles, fishes, molluscous animals, etc.; the preservation of spiders, and preparation of skeletons. The choice and manner of collecting animals, recipes for various articles used in the art, and some instructions to travelers, complete the work. A half-dozen well-engraved plates exhibit the manner of mounting, and preparing the animals and tools used.

author in this pamphlet describes some remarkable phenomena which he has noticed several times in his observations of the solar spectrum. His attention was first called to them on the 30th of August, 1877, when, all at once, the spectrum was crossed, with the quickness of lightning, by extremely brilliant spectra, which succeeded each other rapidly and ran the full length of the spectrum. The phenomenon was observed on the following days to the 3d of September, the fugitive spectra varying in shape and intensity, and appearing at unequal intervals. Some moved across the solar spectrum or parallel to it, others were stationary. The fugitive spectra were next noticed at Creston, Wyoming, during the observations of the eclipse of the sun in July, 1878, and again at different intervals till the 2d of February, 1880, when the last observation described in the memoir took place. They generally came in numbers, not alone, and in spells of several days at a time, separated by intervals sometimes of months. M. Trouvelot does not derive from this any theory as to the frequency with which they may really have manifested themselves; for, though he saw them only fifteen times in thirty months, he was actually observing the sun for only one hundredth of the time during that period, and they may have been active during the other ninety-nine hundredths of the time without his noticing them. He satisfied himself by every possible experiment and form of reasoning that they were not of terrestrial but of cosmical origin. Two theories are proposed to account for them: 1. That they arise from the meteoric bodies that are supposed to be constantly falling into the sun; 2. That they come from the incandescent matter which the sun throws up in the eruptions which have been observed to take place from its surface. M. Trouvelot prefers the latter theory.

one may be pardoned for slightly altering the hackneyed citation, by asserting that "westward the star of science takes its way." In this contribution of the Davenport Academy is that of which the elder academy in the East need not be ashamed. We notice, too, this Western academy is appointing its professors after the methods of the Eastern one. In these proceedings we find original work in archæology, botany, entomology, conchology, paleontology, and embryology, and all these illustrated by plates. The most labored and lengthy article is one by J. Duncan Putnam, on the maple-bark scale-insect (Pulvinaria innumerabilis). This article is very exhaustive, and of great biological merit. There is a short but interesting paper by Dr. R. J. Farquharson, on the formation of ground-ice in the rapids of the Mississippi. This is a revival of the long mooted question, How is anchor-ice made? Dr. Farquharson gives the bibliography of the subject. The Doctor's theory in a nutshell is this: that rapidly-flowing water will get so mixed that its temperature becomes uniform throughout, and when at its freezing-point an arrest of motion will favor congelation, so that there is needed "but the slack-water afforded by the eddy of a bowlder, or a pot-hole, to freeze instantly into a spongy mass." We wish this Western academy the prosperity it so well merits. For two things is this Iowa institution notable: that it is indebted for its building site to a noble-hearted woman, Mrs. P. V. Newcomb; and its president is Mrs. Mary