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The Museum Committee of the County Borough of Cardiff require the services of a CURATOR of the Museum and Art Gallery, who will also act as SECRETARY to the Committee. The gentleman app inted will be required to devote the whole of his time to the duties, and must be competent to Catalogue the contents of the Museum and Art Gallery, and to collect Specimens for the Museum. The Salary will commence at £200 per annum, rising by annual increments of £10 to £250 per annum. Preference will be given to Applicants who have previously held Office in a Museum. The person appointed will be required to enter upon his Duties APPOINTMENTS.-House Physicians, House Surgeons, &c. Forty of these Appointments are made annually. Dressers, Clinical Clerks, &c., appointed every Three Months. All are free to Students of the College. Holders of Resident Appointments have Free Board. SCHOLARSHIPS AND PRIZES.-Twenty-four Scholarships and Prizes are given annually. 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Special Classes for the Examinations of the University of London are held throughout the year. THE ELECTRICAL AND GENERAL ENGINEERING COLLEGE. AND SCHOOL OF SCIENCE. PENYWERN HOUSE, 2 PENYWERN ROAD, EARL'S PRINCIPAL-G. W. DE TUNZELMANN, B.Sc., M.L.EE. The Complete Courses qualify Students for entry into Electrical or The First Year's Course is arranged to qualify Students fr Cooper's Hill, the Central Institution Engineering College, or the Ray School of Mines. Forty-one Students have entered these Institutions during the three years, and two Entrance Scholarships have been obtained at Central Institution. The College is provided with very complete Laboratories and Dan room, and also with an extensive Geological Collection for the Preli Courses for Civil and Mining Engineering Students. Students are regularly sent to the College by Leading Engineers and Scientific Authorities, whose Names are given in the Prospectus. LECTURE DIAGRAMS, Tabular or Pic torial, for Medical and Scientific Lectures, enlarged from Bokse Drawings. References to London Lecturers.-Miss IBBS, & Bruasent Square, W.C. A Fine Binocular Microscope (Largest) by Ross, with Apparatus and High-class Objectives from 2 inch tai Objects fitted in Cabinets, &c. Cost nearly £200. To be sold cheap Equal to new-HUGHES, Brewster House, Mortimer Road. King, land, N. To Collectors and Buyers of Precious and Fancy Stones.-R. C. NOCKOLD, Diamond and Oriental Stine Mer chant, 12 Frith Street, Soho, W., has a very large assortment of Spa men Stones, cut and uncut. Fine Collection of Coloured Diamo and in Matrix. Inspection invited. A Register of approved lodgings, and of private families receiving LIVING SPECIMENS FOR THE Boarders, is kept in the Secretary's Office. Prospectuses and all particulars may be obtained from the Medical Secretary, Mr. G. RENDLE. G. H. MAKINS, Dean. UNIVERSITY COLLEGE, LONDON. FACULTY OF MEDICINE. The SUMMER SESSION begins on MAY 1. The work is arranged so that a student may advantageously begin the Science part of the Medical Curriculum then. Full information may be obtained from either of the undersigned. E. A. SCHÄFER, F. R.S., Dean of the Faculty. J. M. HORSBURGH, M.A., Secretary. GRESHAM COLLEGE, BASINGHALL STREET, E.C. A Course of Lectures on Special Applications of the Laws of Chance will be given as follows: Tuesday, April 18, JOHN VENN, Esq., Sc.D., F.R.S., "On Frequency Curves, their Nature, Variety, and Use." Wednesday, April 19, Prof. W. F. R. Weldon, M.A., F.R.S., "Chance in the Field of Biology." Thursday, April 20, the Rev. W. A. WHITWORTH, M.A., "On some Points in the Philosophy of Chance." Friday, April 21, Sir ROBERT S. BALL LL.D., F.R.S., " Probability as he Guide of Astronomers.' The Lectures, which commence at 6 pm, are Free to the Public. A detailed Syllabus may be obtained at the College, MICROSCOPE. Volvox globator, Epistylis flavicans. 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WILLIAM HUME, I Lothian Street, Edinburgh. recent years, be found embodied. It has been a colossal enter prise. Every map is up to date, not only in such vas territories as Equatorial and Southern Africa, but in regard t matter so limited in area as the fishery dispute in Newfoundla.. where the French shore is clearly marked.”—Bradford Obser........ CASSELL & COMPANY, Limited, LUDGATE HILL, LONDON. JOURNAL OF THE INSTITUTION OF ELECTRICAL ENGINEERS. Edited by F. H. WEBB, Secretary. Part CIV. Containing the conclusion of the discussion on Prof. J. A. Fleming's ALTERNAL Paper, EXPERIMENTAL RESEARCHES ON CURRENT TRANSFORMERS," and his Reply.-"TESTING AND WORKING ALTERNATORS." by W. M. Mordey, Member, and De cussion thereon.-Also two interesting Original Communications, "NOTES ON A SELENIUM CELL," by E. O. Walker, CIE. Member; and "A NEW DANGER TO WHICH UNDERGROUND WIRES IN INDIA ARE EXPOSED, by C V. Luke. C.I.E., Member -Classified List of Articles relating to ELECTRICITY and MA NETISM contained in some of the principal Technical Journals during the months of January and February, 1893, and Abstracts of some of the published during the months from June to December, 1892. Price Two Shillings and Sixpence. Messrs. E. & F. N. SPON, 125 Strand, W.C. Now Ready, Profusely Illustrated, Price 7s. 6d. PEDDIE'S UNIVERSITY MANUAL OF PHYSICS London: Baillière, Tindall, & Cox, King William Street, Strand Just Published, Price 35. 6d, Post Free. MAP OF RIVER BASINS, ENGLAND AND WALES, in County Council Groups. By C. E. DE RANCE Assoc. Inst.C.E., F.G.S., F.R. G.S., F.K.Met.Soc., &c. J. E. CORNISH, 16 St. Ann's Square, Manchester. THURSDAY, APRIL 13, 1893. THE PLANET MARS. La Planète Mars et ses Conditions d'Habitabilité. Par Camille Flammarion. (Gauthier-Villars et Fils, 1892.) IN this very handsome volume the author brings together every available observation and piece of information that can be gathered from published and unpublished works with respect to our sometimes very near neighbour, the planet Mars. To make such a com The second drawing, which was made on August 24, two years later, was accompanied with the text :— "Martis pilula, vel niger conus, intuebatur distincte ad circuli, ipsum ambientis, deliquium, proportionaliter deficere quod fortarse Martis gyrationem circa proprium centrum significat." Following Fontana; Riccioli, Hirzgarter, Schyrle de heita, Hévélius, and Huygens (1656) were the next to make a special study of this planet, the last mentioned of whom added much to the knowledge of the planet's surface markings. Up to the end of this period (1830) the number of observers, and consequently the number of observations had very much pilation as this, is, as every one will acknowledge, no light increased, while the rapid stride made in the perfection task; and since up to the present no one has made any attempt to collect existing observations and discuss them (although perhaps the value of this book is the more enhanced thereby) the difficulty of the undertaking has been very considerable, but in such hands as M. Flammarion's it has been thoroughly mastered. With regard, first, to the form of arrangement which the author has thought advisable to adopt since in a work of this kind many courses are open depending on the standpoint from which the book is written-the writer might, in the first instance, have divided the text into chapters dealing with the climate, calendar, heat, mass, density, geography, &c., treating each of these at full length, and discussing all the observations bearing on each separately. That this would have formed a good and logical sequence is unquestionable, but it is accompanied by many drawbacks, the chief of them being that as observations increased and our knowledge consequently advanced, each part of the work would have to be rewritten, or, at any rate, undergo a thorough revision. The method actually chosen is one which will seem more simple and therefore appeal more to the astronomer, and will perhaps be productive of better discussion. M. Flammarion places the facts before the reader in simple, chronological order, tracing out the work on the planet from the very first observations, step by step, down to those made during the opposition of 1892. The volume is divided into two main parts, the first including the exposition and discussion of the observations themselves, and the latter containing the conclusions that have been drawn from the study of all the facts. The interval from 1636 to 1892-that is the whole time covered by our records-is divided into three chief periods, the first two of which terminate in the years 1830 and 1877 respectively. Dealing first with the period commencing with the observations of Fontana (1636-1638), we are at one of the most interesting parts of the book. Here the author has been plunging into all the old original records, and has treated us to the tit-bits both as regards illustrations and text. As we cannot here conveniently produce the earlier drawings of the planet as made by Fontana, but which are represented in this volume, we may at least give the original observations as recorded in words : of the telescope was not the least important factor in this advance. Summing up the conclusions which can be that they related more to the elements of the planet drawn from these 192 years of observations it may be said than to its surface features, although spots varying in size had been many times noticed; the general idea of the different shadings as representing land and water had been thrown out, and the polar caps had been recorded as variable and not coincident with the geographical poles. The second period, commencing in the year 1830, opens with an account of the fine series of observations made by Beer and Mädler. It was about this time that the real geography of the planet's surface began to be better known, and a systematic method of mapping brought into vogue. Following these two workers come a host of others, all adding their mite, in some cases rather a large one, to solve the riddle relating to this orb. Among these we may mention; Warren de la Rue, Secchi, several of whose fine drawings are here inserted; Lockyer, whose drawings, sixteen of which appear here, and “sont les plus important pour la connaissance de Mars de tous ceux que nous ayons étudiés depuis les premières pages de cet ouvrage"; Phillips, Lord Rosse, Lassell, Kaiser, these, and many others as able, but whose names are too Flammarion, Trouvelot, &c. With such observers as numerous to mention, it is no wonder that good work was done, and our knowledge by the year 1877 greatly extended. More accurate values for the elements were deduced, land and water features confirmed, cloud drifts observed, variations in the polar caps again noticed, &c., in fact, to put it shortly, all observations pointed to a singular likeness of Mars, physically speaking, to the earth herself. In the third and last period-the Martian cycle from 1877 to 1892-we have observations extending over as many as 239 pages of the volume. The epoch commences very appropriately with Prof. Asaph Hall's discovery of the two small satellites, and introduces to us the observations of Schiaparelli, whose work on this planet has been rewarded by such brilliant discoveries. To enter, however briefly, into the mine of interesting and valuable material here brought together would lead us far beyond the limits of this article, but we must leave it to the readers of this journal to refer to the book itself; suffice it to say that M. Flammarion has given each observer his just due and merit. Arriving now at the second part, which gives the results deduced from the general study of the planet, M. Flammarion is also quite at home, and in his masterly way |