MESSRS. MACMILLAN AND CO.'S NEW BOOKS. A NEW BOOK BY MR. J. NORMAN LOCKYER. THE METEORITIC HYPOTHESIS OF THE ORIGIN OF COSMICAL SYSTEMS. By J. NORMAN LOCKYER, F.R. S., Correspondent of the Institute of France, Professor of Astronomical Physics in the Normal School of Science, &c. 8vo, 17s. net. The Times says:-"The book may well be regarded as by far the most important publication of the current week. Norman Lockyer's book is one which no astronomer can neglect." Mr. THE THEORY OF LIGHT. BY THOMAS PRESTON, M.A., Trinity College, Dublin; Lecturer in Mathematics and Mathematical Physics, University College, Dublin. 8vo, 12s. 6d. The Athenæum says:-"There has been a want for many years past of a good English text-book of physical optics. . . . This want is in a large measure supplied by the work before us.. The style is lucid, and numerous historical references and quotations are introduced, which give additional interest to the subject. 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Branches: 45 CORNHILL; 122 REGENT STREET. Photographic Studio-CRYSTAL PALACE, Sydenham. TELEPHONE No. 6583. Telegraphic Address-" NEGRETTI, LONDON." THE SCHOOL BOARD FOR LONDON require the Services of a SCIENCE DEMONSTRATOR, who will be required to visit Schools under the direction of the Board, for the purpose of giving Instruction in Mechanics, &c. The person appointed will be required to give the whole of his time to the work of the Board. Salary, £175 a year, rising by £5 annually to a maximum Salary of £200 a year, together with actual travelling expenses for the conveyance of apparatus from school to school, and for assistance in experiments. Applications, which must be made on Forms, to be obtained from the CLERK OF THE BOARD, must be forwarded to the CLERK OF THE BOARD, School Board for London, Victoria Embankment, W.C., with Endorsement outside, "Science Demonstrator," and must be received on or before DECEMBER 4, 1890. UNIVERSITY COLLEGE OF NORTH WALES. 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ALEXANDER, M. A., Secretary. KING'S COLLEGE, LONDON. DEMONSTRATOR IN ELECTRICAL ENGINEERING. The Council are now ready to receive Applications for this Appointment. For Particulars apply to J. W. CUNNINGHAM, Sec. TWO ENTRANCE SCHOLARSHIPS IN NATURAL SCIENCE, of the value of 125 Guineas (ie. a free admission) and £60, are awarded annually in OCTOBER at ST. THOMAS'S HOSPITAL MEDICAL SCHOOL, London, S. E.For Particulars, apply to Mr. G. RENDLE, Medical Secretary. F. NETTLESHIP, Dean. G. H. MAKINS, Vice-Dean. THE AGRICULTURAL COLLEGE, ASPATRIA. PRINCIPAL-DR. H. J. WEBB, B.Sc. Thorough practical and scientific Training in Agriculture. Preparation for the Colonies. Students gained the First, Third, and Fourth Scholarships of the Royal Agricultural Society, 1888; First in Agriculture Junior Scholarships, 1889; First in Agriculture Senior Scholarships, 1890. PRACTICAL PHYSICS FOR B.Sc. AND INT. B.Sc. (Lond.) -A specially arranged Evening Course in the above commences in NOVEMBER. -For Particulars, apply W. G. WOOLCOMBE, M.A. (Oxon.), B.Sc. (Lond.), 101 King Edward Road, South Hackney, N.E. LIVING SPECIMENS FOR THE MICROSCOPE. GOLD MEDAL awarded at the FISHERIES EXHIBITION to THOMAS BOLTON, 62 BALSALL HEATH ROAD, BIRMINGHAM, Who last week sent to his subscribers Stephanoceros Eichornii (the Crown Animalcule), with sketch and description. He also sent out Trout Ova, Philodina roseola, Floscularia, Corethra plumicornis, Melicerta ringens; also Amoeba, Hydra, Vorticella, Crayfish, Dog-Fish, Amphioxus, and other Specimens for Biological Laboratory work. Weekly Announcements will be made in this place of organisms T. B. is supplying. Specimen Tube, One Shilling, post free. Twenty-six Tubes in Course of Six Months for Subscription of £1 1 or Twelve Tubes for 10s. 6d. Portfolio of Drawings, Eleven Parts, Is. each. BY A 24, WANTED FOR SALE. " IBIS," from the Commencement to October 1890. The first 16 Volumes are handsomely bound in Half Calf, and the remainder in Parts as issued."NATURE," from the Commencement to June 1890. First 12 Volumes are Half Bound, and the remainder in Numbers as issued. The whole are in perfect condition, and no reasonable offer will be refused.-Apply, Messrs. MAWSON, SWAN, AND MORGAN, Grey Street, Newcastle-on-Tyne. CEYLON, JAVA, BORNEO, AND NEW GUINEA INSECTS, especially Lepidoptera and Coleoptera, single or in lots. Also Orthoptera and Dragon-flies, Land and Freshwater Shells, offered at cheap prices.-H. FRUHSTORFER, Naturalist, care of German Consulate, Soerabaia, Java. TO BOTANISTS.-FOR SALE: FOUR CASES OF SPECIMENS (Scientist's Collection), beautifully Preserved, Mounted. Named, and Classified. Lathe wanted.-Letters to HEAD MASTER, Marlborough Street Board School, S.E. OSTEOLOGICAL SPECIMENS, MODELS, &c.-MOORE BROS., 49 Hardman Street, Liverpool. Price List, Three Stamps. BRADY & MARTIN, 27, 29, & 31 MOSLEY STREET, NEWCASTLE-UPON-TYNE, Wholesale and Export Dealers and Manufacturers of Chemical and Scientific Apparatus, Pure Chemicals for Analysis, &c., Supply Colleges and Schools in all parts of the World with every requisite for Theoretical and Expérimental Work in Chemistry, Sound, Light, Heat, Magnetism, Electricity, &c. Analytical & Works Laboratories completely Furnished. Agents in connection with the Science and Art Department. 9 WE THURSDAY, NOVEMBER 27, 1890. THE UNITED STATES CENSUS. E are surprised that so little attention is being given here to the totals of the United States census which are just being published. There is no more important record in the life of a people than its census. Accounts of progress are impossible without it. In the United States, also, special attention is given to the census, partly because it is a requirement of the Constitution, which assigns representatives to States and districts in accordance with the population figures. Every ten years, in the United States, there is a vast outlay on the business, with which outlay nothing spent in Europe can compare. But now there are loud complaints all over the United States that the record for 1890 is wrong; that the population of cities and places has been miscounted grossly. If these complaints are true, the United States might almost as well have had no census at all. All the elaborate work which is to be based on these population figures is rendered useless before it is begun Apart from the direct loss to the United States people themselves, who lose the information about their own affairs the census might have given them, the whole world sustains a loss in being deprived of comparisons of many kinds with so remarkable a progress as that of the United States. Has a colossal blunder, then, been made? and what can be the reason of it? That there is a huge blunder, or worse, somewhere, appears quite unmistakable. Those who are interested have only to cast their eye over the following table to see that something unusual happened to the 1870 census, and has again happened to the 1890 census : Population of the United States, since 1800, and increase in each decennial period. In all this long period the increase of population in the United States has been at the nearly uniform rate of a third every ten years, with the two exceptions of the 1870 census and the 1890 census, in which the increase is respectively 23 and 24 per cent, only. What can have happened, first between the 1860 census and that of 1870, and next between the census of 1880 and that of 1890, to make the results so different from those of all the other periods? Now, what happened between 1860 and 1870 is partially explainable. These were the years of the great Civil War, in which privation and disease, with death and injuries on the battle-field, had their thousands and millions of victims. Such causes are well known to check the growth of population. Unfortunately, also, there is Unfortunately, also, there is another partial explanation. It has been admitted on the highest authority, that of General Walker, who supervised the census of 1880-and the admission is now repeated by the superintendent of the 1890 census-that the figures of the 1870 census were in some States falsified, with the result that in 1880, when the census of that year was taken, an impossible increase of population appeared to have occurred in those States. As far as amount is concerned, however, the former explanation has always been understood to be the more serious. Can any such explanation be given of the small increase between 1880 and 1890? The answer is obvious. There has been no war or the like occurrence since 1880 to check the growth of population. There is absolutely nothing to suggest why the United States population, having increased most rapidly from the beginning of the century down to 1880, excepting during the war decade of 1860-70, should have suddenly had its rate of growth arrested. More than this, the period between 1880 and 1890 has been one in which, according to past experience, owing to the special magnitude of the immigration, the rate of growth should have been as great as in any of the previous periods. The amount, and proportion to the population at the previous census, of the immigration into the United States since 1820, has been : Thus, between 1880 and 1890, as far as the element of immigration is concerned, the growth of population in the Unites States was as much stimulated as in any previous decade, with the single exception of the 1850-60 period. There was absolutely no reason, then, why the rate of growth should fall off between 1880 and 1890, but a special reason why it should not fall off. When we compare the figures in amount, we are still more bewildered. Between 1870 and 1880, with an immigration of 2,707,000 only, the increase of population is 11,598,000; so that, deducting the immigration, the increase which is due to the excess of births over deaths appears to be 8,891,000. Between 1880 and 1890, with an immigration of 5,275,000, the total increase of population is 12,225,000, and if we deduct the immigration, the increase which is due to the excess of births over deaths appears to be 6,950,000 only! The excess of births over deaths which was nearly 9,000,000 between 1870 and 1880 falls to less than 7,000,000 in the following decade, although the population at starting was 25 per cent. greater in the later than in the earlier decade. Making any reasonable correction for the under estimate in the 1870 census itself, which is now admitted, we still find these figures most startling. Even if we were to increase the population of 1870 to 40,000,000, as the superintendent of the 1890 census now suggests, thus reducing the apparent increase between 1870 and 1880 from about 9,000,000 to about 7,500,000, we should still be confronted by the fact that, starting from a larger population, and with a larger immigration, the excess of |