VOL. 4, part 2 of Osiris, edited by Dr. G. Sarton, published in 1938, is a monograph on “Science, Technology and Society in Seventeenth Century England’, by Robert K. Merton, and its content is defined by the author as “an empirical examination of the genesis and development of some of the cultural values which underly the large-scale pursuit of science”. The “Dictionary of National Biography” has been selected as the source of information of an occupational census and the data subjected to a tabulation process. On the basis of this information a further survey of discoveries based on Darmstaedter's “Handbuch zur Geschichte der Naturwissenschaften und Technik” was compiled. This indicated the particular interests which arose in different times in the period studied. The influence of religious movements such as Puritanism is considered. The influence of external factors is carefully examined. The whole study is very interesting and suggestive in many fields but suffers from the lack of a detailed table of contents, so that the intention of the work is not easy to grasp, and the author's conclusions are not easy to find in the mass of detail. Vol. 5 of Osiris, which now rejoices in a Latin title as Commentationes de scientiarum el eruditionis historia rationeque volumen quintum lulio Ruska oblatum, is dated 1938, and is edited by Dr. Sarton assisted by Dr. Pogo. It contains some interesting and valuable papers on scientific incunabula (to which a recent volume of Osiris was devoted), on Arabic algebra (incidentally, the history of mathematics has occupied a prominent place in the journal so far), on Kopp, the historian of chemistry, on astronomy, on Michael Scot (a subject which has now been about worked to death), on animals in the Bible, and on other subjects. There is a biographical and bibliographical notice of Ruska and a portrait. These two volumes of Osiris maintain the high standard of scholarship of the publication, and are indispensable to students of the history of science.