show in part how important and useful the work of the institution is, and how large a field it covers.
In direct compliance with the programme above given, the institution publishes three classes of works: first, the "Contributions to Knowledge" (quarto), which are memoirs "containing some positive addition to science resting on original research, and which are generally the result of investigations to which the institution has, in some way, rendered assistance;" second, the "Miscellaneous Collections" (octavo), which consist of works "intended to facilitate the study of branches of natural history, meteorology, etc., and are designed especially to induce individuals to engage in these studies as specialties;" third, the "Annual Reports" (octavo) contain, besides the accounts of the operations, expenditures, etc., "translations from works not generally accessible to American students, reports of lectures, abstracts of correspondence, etc." These are liberally distributed free of cost to public libraries, institutions, colleges. States, and Territories, in such a way, and under such conditions, as shall secure them to be most generally accessible and useful. No copyright has ever been secured on any of the publications of the Institution. They are left perfectly free to be used by the compilers of books and all other persons, on the express condition that due credit is to be given, not only to the author of the book, but to the Smithsonian Institution. This is eminently just, because in most cases the researches have been prosecuted with the aid of funds from the Smithson bequest. The publications for 1874 have been Volume XIX. of the "Contributions to Knowledge," which contains the results of three most important researches: 1. On Problems of Rotary Motion, by General J. G. Barnard, pp. '74. 2. On Fresh-water Algæ, by Prof. H. C. Wood, pp. 274, 21 colored plates. 3. Orbit and Tables of Uranus, by Prof S. Newcomb, pp. 296.
Besides this, the eleventh and twelfth volumes of the "Miscellaneous Collections" have been issued, containing nine contributions: On the Families of Mammals and Fishes, by Dr. Theodore Gill; On the Diptera of North America, by H. Loew; Directions for collecting and preserving Insects, by Dr. Packard; two papers on Coleoptera, by Dr. John Le Conte; Review of American Birds, by Prof Baird; On the Constants of Nature, Part I., boiling-points, specific gravities, etc., by Prof Clarke (noticed in The Popular Science Monthly, August, 1874); and Rules for the Telegraphic Announcement of Astronomical Discoveries, by Prof. Henry. Several of the separate memoirs which will make up Volume XX. of the "Contributions to Knowledge" have already been printed and distributed: 1. On the General Integrals of Planetary Motion, by Prof. Newcomb; 2. On the Haidah Indians of Queen Charlotte Islands, by James G. Swan. At the time of making the report, there were in the press, and intended for the quarto publications: 1. The Antiquities of Tennessee, by Dr. Joseph Jones; 2. The Harmonies of the Solar System, by Prof S. Alexander (noticed in The Popular Science Monthly for September, 1875); 3. The Winds of the Globe, by the late Prof. J. H. Coffin; 4. The Temperature Tables of North America, by C. A. Schott. There were also in the press a monograph of American Wasps, by Prof, de Saussure, of Geneva, and a botanical index to all known American species of plants.
For many years the Smithsonian Institution had a large corps of volunteer meteorological observers distributed all over the United States, who forwarded their reports for discussion to Washington. These observers have been transferred to the United States Signal Bureau of the War Department, to whom their reports are now furnished. But an immense amount of valuable meteorological material has accumulated at the Smithsonian Institution, which is to be discussed and published. The first work of this series, on "Rainfall," has already been printed, the discussion of the observations having been done by Prof. Schott, of the Coast Survey. The second volume, on the "Winds of the Globe," by Prof. J. H. Coffin, and continued by his son and by Dr. Woeikof, will be published in 1875. The next work of the series treats of the "Temperature of the United States," and will also be published during this year. It deals with all available observations of
