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PATHOLOGY.

(a) ENGLISH.

() MENTAL PHILOSOPHY
(Logic and Metaphysics and
Moral Philosophy).

PHYSIOLOGY.

CHEMISTRY.

FACULTIES OF ARTS, SCIENCE
AND MEDICINE
The persons to be appointed will hold office for a period of three years
from January 1, 1907.

Applications are also invited for the appointment of an ADDITIONAL EXAMINER for the PRELIMINARY EXAMINATIONS AND BURSARY COMPETITION in ENGLISH. The person appointed to the last-mentioned Examinership will hold office for one year from February 1, 1907. and will act as a Representative of the University on the Joint Board of Examiners of the Scottish Universities. The appointment may be renewed for a second year.

Applications, with eighteen copies of testimonials, must be lodged on or before SATURDAY, JUNE 30, 1906 with the undersigned.

ANDREW BENNETT, Secretary and Registrar.

The University, St. Andrews, May 5, 1906.

COUNTY BOROUGH of WATERFORD.

TECHNICAL INSTRUCTION COMMITTEE.

The Technical Instruction Committee for the County Borough of Waterford invite applications for the following appointments :

(1) HEADMASTER and ORGANISING SECRETARY. Salary £250, rising by 10 annually to £300. Qualifications must include Theoretical and Practical Chemistry and Physics, and Teaching and Organising experience. Will be required to perform the duties of Organising Secretary and Headmaster of Day and Evening Classes, and to supervise equipping of new Technical School. Duties to be commenced on July 1.

(2) MANUAL INSTRUCTOR in Wood and Metal Work. Salary £150, rising by ro annually to £180. Qualifications must include Build. ing Trades subjects, Applied Mechanics, Machine Construction and Metal Workshop Practice. Duties to be commenced in September.

(3) DOMESTIC ECONOMY INSTRUCTRESS. Salary £80, which will be increased by 10 annually to £120. Certificates in Cookery, Laundry Work, Needlework (including Dressmaking), Housewifery and Hygiene required (1st class in Cookery, and in Laundry Work or Needle. work required). Duties to be commence 1 in September.

The candidates appointed will be whole time officers of the Committee, and may be required to give instruction in schools other than the Technical Schools. Applications, stating qualifications, experience, age, and giving references as to character, to be received on or before May 20, 1906, by JAMES J. FEELY, Secretary to Committee.

Town Hall, Waterford.
May 1, 1906.

BIRKBECK COLLEGE,

BREAMS BUILDINGS, CHANCERY LANE, E.C.

FACULTY OF SCIENCE.

DAY AND EVENING COURSES, under Recognised Teachers of the University of London.

Chemistry

Physics...

Mathematice

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Geology & Mineralogy
Assaying, Metallurgy & Mining. GEO. PATCHIN, A.R.S.M.
RESEARCH in Chemistry and Physics in well-equipped laboratories.
French, German, Spanish, Russian, and Italian Classes.
EVENING CLASSES in Biology, Physiology, Practical Geometry,
Building and Machine Construction, Theoretical Mechanics, Applied
Mechanics and Mechanism, Land and Quantity Surveying.
Calendar 6d. (post free 8d.), on application to the SECRETARY.

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MATRICULATION, INTERMEDIATE, final.
PREPARATION by CORRESPONDENCE (Residence abroad no
impediment) or ORAL TUITION on a THOROUGHLY INDI-
VIDUAL SYSTEM. Fees based on success.

The STAFF includes Graduates of Oxford, Cambridge, London, and
Royal Universities, Science Medallists, Prizemen, Scholars, &c.
SINGLE SUBJECTS TAKEN: Science, Mathematics, Logic,
Psychology, Political Economy, Latin, Greek, French, German, &c.
For terms, &c., address Mr. J. CHARLESTON, B.A. (Lond. and Oxon.),
Burlington Correspondence College, Clapham Common, London, S.W.

UNIVERSITY OF

BIRMINGHAM.

FACULTY OF SCIENCE.
RESEARCH SCHOLARSHIPS,
Each of the value of about £96.

(Founded by the late T. AUBREY BOWEN, Esq., of Melbourne, Australia.)
(a) Two BOWEN SCHOLARSHIPS in ENGINEERING.
(6) One BOWEN SCHOLARSHIP in METALLURGY.

(c) Three PRIESTLEY SCHOLARSHIPS in CHEMISTRY.
The object of these Scholarships is to encourage higher work and research
in Scientific Professional Engineering and in Chemical and Metallurgical
Science. Applications, supported by details of educational training, and
references to former teachers and others, should be sent to the REGISTKAR
on or before June 1, 1906. The Scholarships will be tenable during the
Session 1906-7.

Further particulars may be obtained on application to the REGISTRAR.

SCHOOL.

EGYPTIAN GOVERNMENT SCHOOLS. In view of the extension of Secondary Education in Egypt, applications are invited for new ASSISTANT-MASTERSHIPS in Secondary Schools under the Ministry of Education. Masters to begin work in October, in Cairo or Alexandria, and to teach in English exclusively. Over 400 boys CAMBRIDGE UNIVERSITY MEDICAL in each School, mainly Mohammedans. In the case of two of the Masters now required, the subject mainly essential is Science (Experimental Physics and Chemistry); six of the new Masters will be principally engaged in teaching Mathematics; the others will be concerned more particularly with the teaching of English, including History and Geography. Candidates should be not less than 23 nor over 30 years of age, have a robust constitution, and have taken a University Degree in Honours. They should have experience as Teachers: preference will be given to applicants who hold a Diploma in Teaching. Salary, £295 per annum (Eg.24 per mensem), rising to £393 per annum (Eg.32 per mensem). Allowance for passage out to Egypt. Teaching hours, on an average, four daily, Fridays only excepted. Summer vacation not less than two months.

Applications, with full statement of qualifications and accompanied by copies only of testimonials, must be sent in before May 31, 1906, marked outside Assistant-Masterships," and addressed to H. J. BOYD-CARPENTER, Esq., Senior Inspector, Ministry of Education, Cairo, Egypt, to whom candidates may apply for further information.

UNIVERSITY COLLEGE, LONDON.
(UNIVERSITY OF LONDON.)

JODRELL PROFESSORSHIP OF ZOOLOGY AND
COMPARATIVE ANATOMY.

The Council will shortly proceed to fill the vacancy in the Jodrell Chair of Zoology and Comparative Anatomy caused by the appointment of Professor E. A. Minchin to the new Chair of Proto-Zoology in the University of London.

Applications, accompanied by such testimonials and other evidence of fitness for the post as candidates may wish to submit, should reach the SECRETARY (from whom further particulars may be obtained) not later than Saturday, June 9, 1906.

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In addition to the usual courses given in the Pharmacological and Pathological Departments the series of short courses of lectures and demonstrations on Pharmacology (Bronchial Asthma, Vasoconstriction," the Specific Actions of Drugs, &c.), Pathology (Inflammation, Immunity, Antitoxins and Antibodies, Food Poisoning, &c.), and a course by Dr. Nuttall on Protozoal Diseases will be repeated this year.

These courses will be open to Medical Men and Senior Students only; they will be held if a class of ten can be formed, and will not extend over more than four weeks.

Full particulars may be obtained on application to Mr. E. E. STUBBINGS, Pathological Department, New Medical School, Cambridge.

UNIVERSITY OF MANCHESTER. GARTSIDE SCHOLARSHIPS OF COMMERCE AND

INDUSTRIES.

Candidates must be of British Nationality, and over the age of 18, and under the age of 23 at the date of election. The Scholarships, three of which may be awarded in June, will be tenable for two years and of the value of £80 the first year (which must be spent at the University), and from £150 to £250 the second year (which must be spent in the study of subjects bearing on Commerce in the United States, Germany, or other country or countries approved by the electors). Candidates must send in their applications, together with testimonials of good character and record of previous training, on or before June 1 to the REGISTRAR, from whom

BATTERSEA POLYTECHNIC,

BATTERSEA PARK ROAD, S.W.

PRINCIPAL SIDNEY H. WELLS, Wh.Sch., A.M.I.C.E.,

A.M.I.M.E.

GAS ANALYSIS.

A Special Course of Eight Lectures and Laboratory work on Gas Analysis will be given by Mr. JOHN WILSON, M.Sc. (Head of the Chemical Department), on Wednesday evenings, commencing May 23. Lectures, 7.15-8.15; Laboratory, 8.15-9.45. Fee, 5s. For prospectus apply to the SECRETARY.

UNIVERSITY OF LONDON.

GOLDSMITHS' COLLEGE, NEW CROSS. DEPARTMENT FOR THE TRAINING OF TEACHERS. About to additional Teachers (Men and Women) will shortly be ap. pointed in the above Department.

These will include an Assistant Master of Method, an Assistant Mistress of Method (for Infant School Teaching), and teachers of English Litera ture, French, History, Mathematics, Elementary Science.

The majority of the salaries will be, for Men, between £175 and £250 a year; and, for Women, between £150 and £200 a year; but more or less may be paid in exceptional cases.

An Assistant Manual Instructor (salary £100 or £120 a year) is also required

Applications must be received not later than Saturday, June 2, 1906. Particulars may be obtained from the WARDEN, Goldsmiths' College, New Cross, S. E.

UNIVERSITY OF BIRMINGHAM.

TWO ASSISTANT LECTURESHIPS IN MATHEMATICS. The Council invites applications for the above appointments. Stipends, £175 and £150 per annum, respectively.

Applications, accompanied by testimonials, should be sent to the undersigned not later than Tuesday, June 5, 1906.

The candidates elected will be required to enter upon their duties on October 1, 1906.

Further particulars may be obtained from

GEO. H. MORLEY, Secretary. UNIVERSITY COLLEGE OF SOUTH WALES

AND MONMOUTHSHIRE, CARDIFF.

The Council of the College invites applications for the post of DEMONSTRATOR and ASSISTANT LECTURER in ENGINEERING. Further particulars may be obtained from the undersigned, to whom applications with testimonials (which need not be printed) must be sent on before Friday, May 25, 1906.

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Just Published. With 402 Illustrations.

8vo, 24s. net.

The Principles of Electric Wave Telegraphy.

By J. A. FLEMING, M.A., D.Sc., F.R.S., Professor of Electrical Engineering in University College of the University of London. Prospectus sent on application.

LONGMANS, GREEN & CO., 39 Paternoster Row, London, E.C. ROYAL IRISH ACADEMY.

TRANSACTIONS.

Vol. XXXIII. Section B. Part II. With 6 Plates. Price 2s. 3d. A COMPARATIVE STUDY OF THE PLANKTON OF SOME IRISH LAKES.

By W. WEST, F.L.S., and Prof. G. S. WEST, M.A., F.L.S.

ROYAL DUBLIN SOCIETY.

SCIENTIFIC PROCEEDINGS. Vol. XI. New Series. No. 9. Price Sixpence. ON THE VAPOUR-PRESSURE OF A PURE LIQUID AT CONSTANT TEMPERATURE. By SYDNEY YOUNG, D.Sc., F.R.S., Trinity College, Dublin. WILLIAMS & Norgate, 14 Henrietta St., Covent Garden, London, W.C.

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Salary £300, to be increased to £350. Public Assistant wanted in Warehouse of Chemical

College Abroad. Passage, £60. Ditto, Scotland, £210. 20 Science and Mathematical Masters required for Immediate and September

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The Governing Body invite applications for the post of HEAD of the DEPARTMENT of ELECTRICAL ENGINEERING from September Bert. Electrical experience and teaching experience essential.

For particulars send stamped and addressed envelope to the SECRETARY. CADET

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LIVERPOOL.

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MASTERS.-Immediate and September Vacancies.-Graduates and <ther well qualified Masters seeking posts in Public and other Schools should apply at once, giving full details as to qualifications, &c., to Messrs. GRIFFITHS, SMITH, POWELL & SMITH, Tutorial Agents (Estd 1833), 34 Bedford Street, Strand, London. Immediate notice of all the best vacancies will be sent.

(Trade supplied).

CONTRACTORS TO H.M. GOVERNMENT. Catalogues Free on Application. Established 70 Years.

A Research Student is required in the MURIEL STREET, CHARLOTTE STREET,

Chemical Department of an important Technical Institution to work under the immediate direction of the Professor. An allowance of £60 per session towards maintenance will be paid.-Address, stating training, age and qualifications, to No. 10 at the office of NATURE.

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NEARLY READY. In Crown 8vo. Fully Illustrated. MINERAL OIL TESTING. By J. A. HICKS, Chemist to Sir Boverton Redwood.

Re-set on larger page. With valuable Bibliography, New Maps, &c. PETROLEUM AND ITS PRODUCTS. A Practical Treatise. By Sir BOVERTON REDWOOD., D.Sc., F.R.S. E., F.I.C., Adviser on Petroleum to the Admiralty and Home Office, Consulting Adviser to the Corporation of London under the Petroleum Acts, Adviser on Petroleum Transport to the Thames Conservancy.

NEARLY READY. Second Edition. Re-written.

Second Edition. Revised. Fully Illustrated. 155. HEAT. Being Volume III. of a Text-Book of Physics. By J. H. POYNTING, Sc.D., F.R.S., and J. J. THOMSON, M.A., F.R.S. In Large 8vo, Handsome Cloth. Fully Illustrated. 8s. 6d. "Well up to date, and extremely clear and exact throughout."-Nature.

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THURSDAY, MAY 10, 1906.

THE CELL IN MODERN BIOLOGY. Algemeine Biologie. Die Zelle und die Gewebe. Second edition. By Oscar Hertwig. Pp. xvi+648; 371 illustrations. (Jena: Gustav Fischer, 1906.) Price 15 marks.

THE volume before us appears as the second edition

of the author's well known treatise on the cell, the first part of which was published so long ago as

1802.

Cytology has advanced a good deal since that time, and one finds a significant recognition of its wider scope in the new title-" General Biology "—given by Prof. Hertwig to his book. Experience is showing that the larger problems connected with living things, such as organisation, heredity, function, as well as those abnormal reactions constituting what we call pathology, are all reducible to cell problems.

For the most complex living creature is resolvable into groups of more or less modified cells, and the atter are not merely bound together like faggots in a bundle, but each group, each cell it may be, in so far as it is the seat of chemical or physical change, is able in greater or less degree to exert an influence on other individuals of the cell community. In this aay there arise those adjusted relationships that exist between different organs, tissues, and cells tch we designate as correlations, and it is just beause of the existence of these inter-dependent cellular reactivities that complex organisation has come to be a possibility.

the volume does the theory appear to be summarised and presented in a succinct and complete form. But the doctrine it seems to embody is that development and specialisation of function, with the corresponding segregation of structure, are due to the correlative action of the parts on one another coupled with the influence of agencies operating from without-i.e. of the environmental conditions. It is this speculative part of the treatise, suggestive and interesting as it is, that will probably provoke the greatest antagonism. Hertwig is a thorough believer in the inheritance of acquired characters, though it seems not improbable that many will dissent from the interpretations he puts on cases that he apparently regards as critical

ones.

The example of the supposed inheritance of immunity against the poisonous action of ricin, shown. by Ehrlich to occur in the case of the offspring of mice under certain conditions, can hardly be accepted as satisfactory evidence of the "inheritance of acquired characters" as the phrase is critically understood. Indeed, it seems to break down altogether when the conditions under which it may be observed are examined and analysed. Mice are excessively sensitive to the effects of ricin, very minute doses being sufficient to bring about the death of the animal. But by repeated inoculation of sublethal doses of the poison a mouse may reach a state of immunity against the action of a quantity far greater than that which normally proves fatal. The offspring of female immunised mice are themselves also immune, at least during early life, whereas the young resulting from a cross between an immune male and an ordinary female do not exhibit the transmission of the acquired character." In other words, the transmission is confined to the female side. It is evident, however, that such a case is really of no value whatever as evidence of transmission of acquired characters in the proper acceptation of the term. For it is manifest that the young animal during the whole of its existence in utero has been directly exposed to influences that ought to confer immunity upon it, apart altogether from any question of "trans

44

One of the chief aims of Prof. Hertwig's book is to trace the cell in its manifold variety of form and its diverse conditions of activity, especially with reference to the part it plays as a corporate unit of the organism. It is perhaps inevitable that such a task should prove too great for any single writer to accomplish satisfactorily throughout, and, indeed, the present work is by no means free from the faults of its ambition. Some aspects of the subject are exceedingly well treated, others are left comparatively untouched, while in the case of yet others the standpoint taken | mission." Furthermore, it might well be that the up prhaps hardly represents that of contemporary thought. The last criticism especially applies to the discussion of some of the physiological attributes of cell life. Again, the more recently studied phenomena of apospory, apogamy, and parthenogenesis, with their general bearings on the processes of maiosis and fertilisation, are very scantily dealt with. The work is decidedly strongest on the morphological side, although even here the treatment seems to suffer from want of the physiological relationships involved.

A considerable portion of the book is occupied with discussions as to the connection that may subsist between the facts of cell structure and the phenomena of ontogeny and heredity. Brief accounts are given of the standpoints adopted and the theories advocated by other writers, and Hertwig adds another of his oran, which he terms biogenesis.

It is not very easy to extract the author's exact position with regard to biogenesis, and nowhere in

bulky protoplasm of the egg, irrespective of the maternal influence after conception, may have been affected without any disturbance of the hereditary mechanism, and, indeed, Hertwig himself admits as much.

The case of certain Lepidoptera is more difficult of satisfactory explanation, although the evidence would probably be insufficient to convince an opponent. Some of these insects respond to different climatal conditions by the production of different colourpatterns on their wings. Now if the pupæ of some | species (e.g. Arctia caja) be subjected to cold, the cold" form of imago will appear, and if the fertile eggs of such "cold" forms be raised under warmer conditions, a small percentage of the perfect insects thus produced will retain the characters of the cold form. Hertwig dissents from the explanation, suggested by Weismann, that the eggs themselves may have been affected whilst still in the body of the

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parent insect in the pupal condition, but his argument does not amount to much; and it may well be borne in mind that an example of somewhat analogous character is afforded by the alternative characters exhibited by the leaves and other structures of many amphibious plants. Many of these can assume one of two different forms, the production of either depending on the stimulus given by the environment to the embryonic tissues at the growing points. Thus the form of, say, a leaf of such a plant is determined at a very early stage in its development, and long before it is sufficiently advanced for any functionally direct adaptation to a terrestrial or to an aquatic environment. But when once the stimulus has

operated, subsequent removal to opposite conditions does not result in a corresponding alteration inions future development of such a leaf-it belongs definitely to the aquatic or to the terrestrial type, whichever line of ontogeny it embarked on from the first. It would seem, at any rate for the present, and in the absence of sufficient experimental evidence to the contrary, more natural to regard these di- or polymorphic species as "balanced" forms; the actual course of their ontogeny, whilst restricted to certain directions, and confined within definite limits, depending on the alternative character of some metabolic activity. This is, however, very different from an admission of the "inheritance of acquired characters." For if anything at all is meant by the expression, it can only imply that the hereditary mechanism has itself undergone a definite and corresponding change; and at present a direct influence of the environment in this sense is negatived by the results of the most critically conducted experiments on breeding.

Hertwig takes up a definite position as to the relation of the "somatic" to the "germ" cells. He regards all the cells of the body as fundamentally equivalent, though differentiation may mask and finally render impossible the return of a particular cell to the embryonic state. The definite tissue cell has become specialised rather as the result of an impulse from without than by a segregative process of analysis; and herein he is diametrically opposed to Weismann and his followers, in regarding cellular | differentiation as a secondary rather than as a primary matter. In this he will find many who are at one with him, for the "erbungleich" division postulated by Weismann, which would result in development consisting of a sorting out or analysis of the characters of the germ, conflicts with many facts of experience, and it is only by numerous "Hilfshypothese" that it can be sustained for the plant and vegetable kingdoms.

APPRECIATIONS OF HAECKEL.

(1) Ernst Haeckel: Der Mann und sein Werk. By Carl W. Neumann. Pp. 8o. (Berlin: Gose and Tetzlaff, n.d.) Price 1.50 marks.

(2) Haeckel: His Life and Work. By Wilhelm Bölsche, with introduction and supplementary chapter by the translator, Joseph McCabe. Pp. 336; illustrated. (London: T. Fisher Unwin, 1906.) Price 155. net.

(3) Last Words on Evolution: a Popular Retrospect and Summary. By Ernst Haeckel. Translated from the second edition by Joseph McCabe. Pp. 127; with portrait and three plates. (London: A. Owen and Co., 1906.) Price 6s.

(1) MANY who know Prof. Haeckel only as the author of zoological memoirs, evolutionist essays, and monistic propaganda, will be glad of the opportunity which this brightly written booklet affords of becoming more closely acquainted with the man himself and with the story of his life. We read with interest of the eager boy-naturalist wandering on the Siebengebirge, of the apprenticeship under Johannes Müller, of the year of medical practice (if a man can practise on three patients!), of the eventful year in Italy during which Haeckel nearly became a landscape painter, of the growing fascination which the plankton exerted, satisfying at once his artistic and scientific interests, of the influence that the "Origin of Species" had on him, and of his early settlement in Jena-that "feste Burg freien Denkens "—which nothing could ever induce him to leave. At the Stettin Versammlung in 1863 Haeckel entered the lists as a champion of the evolutionist "Weltanschauung," contending almost single-handed against contempt and prejudice. His cause, which eventually prevailed, as the truth must, had to be fought for, and those who are offended by the impetuous expressions of Haeckel's "Stürmernatur are profitably reminded by this little book of the courage and indefatigability of perhaps the most virile protagonist of a thesis which has been one of the greatest contributions made by science to human progress. The author has told the story of Haeckel's life and work with vividness and enthusiasm. He concludes his effective sketch by indicating, somewhat too tersely and vaguely, how it has been possible for him to use the truth that is in !!aeckel in developing a monistic philosophy more satisfying to the human spirit.

(2) Prof. W. Bölsche's study of Ernst Haeckel is, like the frontispiece to the book, a picture in warm colours. The author is nothing if not enthusiastic, and indeed no one can think over the achievements of Haeckel's life without sharing the author's admiration for his hero. If it be true, as the translator says, that "a hundred Haeckels, grotesque in their unlikeness to each other, circulate in our midst to-day," this "plain study of his personality and the growth of his ideas" should go far to replace them by giving us an appreciation approximately true. We should not ourselves have called Bölsche's book, as Mr.

In a notice of a book like this one of Hertwig's, it is natural that the points on which diversity of opinion prevails should occupy a relatively prominent place. But such treatment is in no way intended to detract from or to minimise the great value of the work, coming as it does from one who has himself done so much to advance the subject of which he writes, and whose lucid and suggestive treatment of his theme will always command attention. It is a book that should be read by all who are interested in the ques-McCabe does, a "plain study," for its characteristic J. B. FARMER. features are exuberant enthusiasm and a brilliantly

tions of modern biology.

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