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278 strongly favorable to an affirmative answer. We need not here enumerate the various other reasons presented on this side of the question, such as the immunity of barbarous races from phthisis until they begin to be associated with the whites, its prevalence in convents, harems, and barracks, the frequency of the disease in wives who have nursed tuberculous husbands, etc. Whether the reader admits that the case is proved, the dictates of reason favor the observance of certain precautions, such as not allowing the same person to remain in too constant attendance on consumptives, nor permitting another to sleep with them, securing the most perfect ventilation possible, and the exercise of great cleanliness with immediate removal and destruction of sputa.

The remainder of the book is devoted to a discussion of the effect of tuberculous food, a subject of no less practical importance than the former. The occurrence of tuberculosis among cows and oxen being quite frequent, it is important that every possible means be employed to prevent the consumption of such beef by human beings. Milk from cows affected by this disease is j even more to be feared, owing to the difficulty of preventing its sale, and the fact \ that the greater part of it is consumed without cooking. In addition to this we must consider that milk frequently forms the entire food of young children, and is an important article of diet with invalids, both of whom are more liable to attacks of any new disease than are older and more healthy persons. Aside from the dangerous infective properties, such milk is objectionable as an article of food, owing to its deficiency in fat, sugar, and the nitrogenous elements. The only remedy against these dangers from beef and milk is to be found in a careful, honest governmental inspection of all the meat that comes into our markets, especially at the slaughter-houses, and of the cows that furnish our milk, with particular reference to the existence of this disease. It may be a difficult and expensive undertaking, but, for our safety, it must be done. The book, on the whole, is not intended to quiet the fears of nervous people, or to convince the timid that there is little to be feared from the dreaded scourge—consumption.

are glad to see a new and carefully revised edition of this admirable and standard work, and also that successive editions are called for abroad. Great pains have been taken by the author to give the highest accuracy to the text, and he has appended, in the form of notes, all the new and important information that has accumulated since the first issue. None of these additions discredit what may be regarded as established facts and principles relating to the sun, but they constitute interesting extensions of solar knowledge, together with new and ingenious speculations, the value of which time alone can determine. Professor Young has done well in thus keeping his book sharply up to the time, by which it will maintain its leading position in astronomical literature.

first part of this work gives the history of the attempts to apply electrical force to the propulsion of boats and airships, including the first essay by M. de Jacobi in Russia in 1839, and the experiment of M. Trouvé, which received the applause due to an apparent success at the Paris Exposition of Electricity last year. A controllable balloon proposed by M. Tissandier, and the electro-motor which he would apply to its propulsion, are also mentioned. The second part of the work embraces a full and detailed description of M. Trouvé's electrical motor, its application, and the degrees of speed attained with it. The whole is hopeful for the ultimate success of electro-navigation.

report, though tardy in appearing, has a permanent value that justifies a notice of it at any time. The record of work done is very full in notices of explorations and special investigations in which the Institution has had a part; the list of