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Rh state, and secure adequate rest and sleep. "For health, as well as happiness, moderation and diversity of pursuits arc essential requisites." Tenth and last law: "No intermarriage of blood relations." The principle is kept in view and enforced by frequent repetition that violations of any of these laws work injury from the beginning, the evil increasing as the violations become habitual, and that for years, perhaps, before the sinner perceives that anything of the kind is taking place; even while he may be boastful of his strength and his superiority to the bad effects of his wrong-doing; and that, when the injury is at last revealed, it is generally past remedy.

The injunctions in the second part of the book, for preventing the spread of infectious diseases by stamping them out within the sick-room, are based on the germ theory of disease. The principles on which they are justified, concisely stated, are, that "persons sick of infectious diseases are the breeding hot-beds from which the germs issue; that these germs make of air, drinks, and foods, mediums by which they are carried into the bodies of others; and, that when they once pervade the air, mix with foods and drinks, they can neither be detected nor destroyed; and, as a corollary, that the only time effectually to destroy them is at the bedside as they pass from the bodies of the sick." To wait, as is too often done, till they have escaped, expecting then by sterner measures to stop the spread of disease, "is like waiting until a fire becomes an alarming conflagration before making systematic efforts to subdue it"—and "even far worse." The directions for enforcing this summary disinfection are plain and practical.

have already (March, 1882) given a sketch of Professor Gould's life and astronomical work, both at home and in Cordoba, and a notice of the first publication of the results of his observations in the southern hemisphere, in the "Uranometria of the Southern Heavens." The present volumes embrace a part of the record of his work at Cordoba as it has been pursued, in considerable but not complete detail. At the beginning, the author entertained the hope of being able to publish all the observations in essentially the same form as they had been made, affixing the instrumental corrections separately. The observations of the years 1872-'73 were prepared for the press in this form, but the impossibility of carrying out the plan became manifest as the number of results increased; and at last anxiety arose lest it might not be possible to secure a prompt publication of the results in any shape whatsoever. The observations for the catalogue have therefore been given in the compact form adapted to the requirements of the case; and those of the zones with only so much detail as seemed needful when a large proportion of the stars had been observed but once. The original observations and all the calculations have been preserved for reference. The zones which have been surveyed in these observations cover a breadth of 52° 20' in declination, extending from 23° to 80° south. Previous determinations of position by zone-observations have been essentially differential in their character, in one co-ordinate, at least, when not in both; in the present undertaking, Dr. Gould has endeavored to obtain so-called absolute determinations for all the stars observed. During the eight and a half years of work up to the close of 1880, more than 250,000 stellar observations were made with the meridian-circle; and the number of different stars observed is estimated at 35,000—all belonging to the southern hemisphere. Among the special observations was a careful determination, of positions and proper motion, of fifty-four circumpolar stars for determination of the azimuthal errors of the instrument. Vol. II of the present series contains the observations made in 1872; Vols. Ill and IV, those made in 1873; and Vols. VII and VIII, the zone-observations made in 1875. In making these observations, between declinations 23° and 47°, the normal width of the zone was two degrees, with 10' additional at each margin and extremity for overlap; from 47° to 75°, their width increased with the declination; until, finally, the last five degrees, 75° to