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Rh found no occasion to proceed farther. Being thus left out, he undertook, with dogs and sledges and two companions who proved congenial, the "untried journey" of six hundred miles over the ice fields of the Lewes Lakes and the ice packs of the Yukon River, which had been the contemplated route of the expedition. The start was made about the 18th of March, with little time to spare, because the Yukon was expected to become impassable by the 20th of April. The Chilkoot Pass was achieved in a day, and the rest of the journey was made "downhill with the current of the river at the rate of eight inches to the mile," in weather that became very variable, with now hard freezing and now slush in the middle of the day. The difficulties of the journey must have been formidable, with considerable suffering, besides a week in a hut with the measles, but no complaint further than the mention of the incidents appears in the author's story. On some of the days the thermometer ranged from 10° to 20° below zero at two o'clock in the morning, to 80° above at night, and the author "had one ear blistered by the frost and the other by the sun in the same day." The party arrived at Dawson just four days before the final break-up of the ice in the river. Accounts corresponding in temper and vividness with that of the journey are given of Dawson, the miners and mining, the history of the Klondyke mining enterprise, Klondyke types of character and adventure, the toils and trials and profit and losses of the "Pilgrims," the workings of the Government, and the return home to civilization—which does not appear, after all, to have offered transcendentally superior attractions to those who had experienced the pleasure of adventure.

The History of Physics in its Elementary Branches has been prepared by Professor Cajori in the belief that some attention to the history of a science helps to make it attractive, and that the general view of the development of the human intellect gained in reading a history on the subject is in itself stimulating and liberalizing. The author has had in mind Professor Ostwald's characterization of the absence of the historical sense and the want of knowledge of the great researches upon which the edifice of science rests as a defect in the present method of teaching. The subject is treated by periods. In ancient times the Greeks, while displaying wonderful creative genius in metaphysics, literature, and art, being ignorant of the method of experimentation, achieved relatively little in natural science. The Roman scientific writers were contented to collect the researches of Greek professors. Except in a few instances the Arabs did not distinguish themselves in original research. Writers in the middle ages were only commentators, and knew nothing of personal investigation. The physicist of the renascence abandoned scholastic speculation and began to study Nature in the language of experiment. The seventeenth century was a period of great experimental as well as theoretical activity. In the eighteenth century speculation was less effectively restrained and guided by experiments. The nineteenth century "has overthrown the leading theories of the previous one hundred years, and has largely built anew on the older foundations laid during the seventeenth century." The evolution of physical laboratories, first for teachers and then for students, is the subject of the last chapter.

"The Great Commanders Series" of D. Appleton and Company is enriched by a biography of General Sherman whom the author, General Manning F. Force, styles "the most picturesque figure in our civil war." He was more than this; he was its scholar and statesman—a man distinguished by the possession of high military combined with the best civil qualities. Further, as General Force well says, "his character was absolutely pure and spotless." In his dealings with the Vigilance Committee in San Francisco he assumed a position which it required courage of a much higher order than a soldier's to maintain. While comfortably situated as an honored professor in the State Military Academy of Louisiana when the Legislature passed the Ordinance of Secession, he had no