Page:Popular Science Monthly Volume 6.djvu/385

 (k.) The placing of revolving lights on our light-ships. Experience has shown this to be possible, as in Great Britain 30 out of 43 light-ships have revolving lights, while in our own service the only lights so placed are constant.

These recommendations are well worth the consideration they will obtain, for the subject is an important one, not only to light-house boards, but to all those who "go down to the sea in ships," as who does not in these days of steam?E. S. H.

second American contribution to the "International Scientific Series" was published December 4th, simultaneously in London and in New York. Translations of it into the Continental languages are in rapid progress, and it will be shortly published in Paris, Leipsic, Milan, and St. Petersburg, so that the views presented by the writer will thus promptly be laid before the leading minds of the civilized world—thanks to the progress of science, which has given us these vast facilities of rapid intercommunication and diffusion of knowledge, and created a liberal public sentiment in all the leading nations by which the expression of advanced opinions is welcomed and appreciated. No more appropriate work could have been done at the present time than to write the history of that long and terrible conflict between the agencies of intolerance and of liberalization which has given rise to modern civilization, and triumphed in that large measure of free opinion which the present age enjoys. In writing such a history, Dr. Draper has done an important service to his time.

Our readers have been already apprised of the nature of Dr. Draper's work, through the statements of the Preface, which appeared in the December and elsewhere, in the present number, we have spoken of its bearing upon great questions now extensively agitated in the public mind. It only remains to add that it is a book to which no notice or review can do justice, because it requires to be read as a whole, like a novel with a well-sustained plot. It is a book crowded with varied information, presented in historic unity, a monograph illustrating and elucidating a single great idea. One of the incidental characters of the volume is the large amount of interesting information it contains regarding the progress of scientific knowledge. Dr. Draper gives us a succession of vivid pictures of the state of actual science among the early Greeks and the later Romans, at the birth of Christianity, at the epoch of the "Fathers of the Church," in the middle ages, at the period of the rise of modern knowledge, at the time of the Reformation, and in the present century. We know of no work that can compare with this volume in the clearness and fullness of its summary of man's scientific achievements from the birth of knowledge to the present time; and, although these copious facts have been gathered and digested by Dr. Draper for the elucidation of his main subject, they are nevertheless of great value and interest, independent of the use he makes of them. All parties are certain to appreciate and enjoy this valuable portion of Dr. Draper's book.

We are constrained also to call attention to the admirable character of the work as a literary exposition. We often hear about the "dryness," and "repulsiveness," and "hard technicality," and general dullness of scientific writers, and the objection is often too well taken, but it does not apply to Dr. Draper. He writes with a clearness, a simplicity, and a warmth of feeling, that give pleasure to the reader, and he thus gains the chief object of an interesting style. Though a discoverer in science, and one who has spent a large portion of his life in the laboratory, and written many original scientific memoirs, he is not the victim of these pursuits, but has cultivated the graceful in literature and given play to imagination, not only in his beautiful researches, but also in his pages, which are often models of forcible and impressive statement. There are many passages in his writings which, for felicity of expression and sheer eloquence, deserve to be placed among our gems of literature, and the reader will find many such examples in his newly-published volume. We are impelled to call attention