Secchi, researches which are always going on; the reader will find with interest various important results of these studies—for instance, the existence in many stars of a good number of terrestrial substances—hydrogen, nitrogen, magnesium, sodium, etc.
One of the most interesting facts is the observation of the temporary star which appeared in May, 1866; the great brightness of the star was due, as indicated by the spectroscope, to an immense mass of incandescent hydrogen.
At the end of the work the author gives some very important observations of Huggins and others on the spectrum of nebulæ; the chief result is the possibility, with the aid of the spectroscope, of distinguishing by the composition of their light the true nebulæ from the clusters of stars.
Finally, a description of the spectrum of the aurora borealis, the identification of its bright lines with some bright lines of the solar corona, a description of various meteors, lightnings and their spectra, show into what difficult objects this new branch of science has pushed its investigations.
On the whole, this book must be considered as a good type of a "popular work;" it deserves the attention of the public, and the esteem of scientific men; and, finally, it recommends itself by a gracious side. It was translated into English by two ladies, who have had the double merit of giving a proof of their good scientific taste, and of showing an example of the help which their sex is able to afford to science.
Life in Nature.—Man and his Dwelling-Place. By James Hinton. New York: D. Appleton & Co.
These works are unique in the scientific literature of the present time, and, although treating of different topics, are so characterized by a common spirit and method, that they may properly be considered together. Their author is a London surgeon in busy practice, but who has not permitted the pressure of professional duties to prevent him from giving close attention to the grave questions by which the mind of the age is agitated. Nor is Mr. Hinton a mere amateur who recreates with philosophy; he is a pioneer investigator in the field of science, and has occupied himself much with those new and large dynamical questions, and their various applications, with which scientific philosophers have been so intently engaged during the last quarter of a century. His inquiry into the physical conditions of vegetable growth, showing that it is governed by definite and traceable forces, and takes place in the direction of least resistance, like all mechanical effects, forms an important contribution to biological science, and was arrived at independently by Mr. Hinton and Herbert Spencer. Yet the author of these works has not dedicated himself to any line of special research (although from the fertility of his ideas, and the acuteness and originality of his views, he might, undoubtedly, have done so with eminent success); but, having mastered the more vital and comprehensive principles of modern research, he takes them as the starting-point for still larger views. Science, indeed, in its ordinary acceptation, is not to him an end. Though deeply imbued with its spirit, and equipped with its latest results, he is not satisfied to rest in this sphere of ideas: it is as leading to something beyond, or as furnishing a basis for something higher, that they have to him their principal value. As Bacon holds science subordinate to the ends of utility, and the practical service of humanity, Mr. Hinton would make it subordinate to the unfolding of man's spiritual nature. He prizes science chiefly for its religious uses, or as an interpretation of the divine order of the world. Maintaining the fundamental harmony of all truth, and that religion represents a verity of the universe as much as astronomy, he has taken it as his task to elucidate the harmonies that must prevail among the different aspects of truth in order that religious faith may be grounded in scientific principles. The results of science, and the knowledge we have of man and the external world, are the author's postulates; and from these he aims to pass, by unbroken logic, to the spiritual order of being. Holding Nature to be a sphere divinely designed for man's highest development, he admits no breaks in the order, and insists that the former must be understood before the latter can be determined. Science, therefore, according to Mr. Hinton, is