BALLIOL COLLEGE, CHRIST CHURCH, AND TRINITY COLLEGE, OXFORD.

A Combined Examination for Natural Science Scholarships and Exhibitions will be held by the above Colleges, beginning on TUESDAY, DECEMBER 4, 1906.

Three Scholarships and two Exhibitions will be offered; with one exception the value of these endowments will be £80 a year.

The Subjects for Examination will be Physics, Chemistry, and Biology. Candidates will not be expected to offer more than two of these.

Particulars may be obtained by application to D. H. NAGEL, Trinity College, Oxford.

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...

Mathematics

Botany

Zoology..

(ALEX. MCKENZIE, Ph.D., D.Sc.,

M.A.

H. WREN, Ph.D., B.A.. B.Sc. ALBERT GRIFFITHS, D.Sc. D. OWEN, B.A., B.Sc.

B. W. CLACK, B.Sc.

E. H. SMART, M.A.

1C. V. COATES, M.A.

V. H. BLACKMAN, M.A.

H. W. UNTHANK, B.A, B.Sc. J. W. EVANS, D.Sc.

Geology & Mineralogy
Assaying, Metallurgy & Mining. GEO. PATCHIN, A.R.S.M.
RESEARCH in Chemistry and Physics in well-equipped laboratories.
French, German, Spanish, 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 3d. (post free 5d.), on application to the SECRETARY.

CITY OF LONDON COLLEGE.

ACTING IN CONJUNCTION WITH THE LONDON CHAMBER OF COMMERCE. WHITE ST., and ROPEMAKER ST., MOORFIELDS, E.C. (Near Moorgate and Liverpool Street Stations.) PRINCIPAL: SIDNEY HUMPHRIES, B.A., LL.B. (Cantab.)

EVENING CLASSES in ALL BRANCHES of SCIENCE. Well-equipped LABORATORIES for Practical Work in CHEMISTRY, BIOLOGY, BOTANY, GEOLOGY, and all branches of PHYSICS.

Special Courses for London University Matric., Inter., and Final B.A., B.Sc., Conjoint Board, Pharmaceutical and other examinations. Classes are also held in all Commercial Subjects, in Languages, Literature and Art. All Classes are open to both sexes.

SATURDAY COURSES for Matric., Inter., and Final B.A., B.Sc DAY COMMERCIAL and HIGHER COMMERCIAL SCHOOLS. Prospectuses, and all other information, gratis on application.

DAVID SAVAGE, Secretary.

TUITION BY CORRESPONDENCE (Residence abroad no impediment).

For MATRICULATION, B.A., B Sc., RESPONSIONS, SCHOLAR-
SHIPS, and PROFESSIONAL PRELIMINARIES.
Tuition in Latin, Greek, French, German, Italian, Spanish, Mathematics,
Mechanics, Physics, Chemistry, Psychology, Logic, Political Economy.
Book-keeping.

The staff includes graduates of Oxford, Cambridge, London, and Royal Universities.

Address Mr J. CHARLESTON, B.A., Burlington Correspondence College, Clapham Common, London, S. W.

KING'S COLLEGE, LONDON.
(UNIVERSITY OF LONDON.)

The Council invite applications for the post of DEMONSTRATOR of PHYSIOLOGY. Salary, £75. Applications should be sent in by November 26. For conditions apply

CALCUTTA UNIVERSITY.

NOTICE.

In January, 1907, the Senate will proceed to appoint a whole-time officer as REGISTRAR of the UNIVERSITY on a salary of Rs.800 per mensem, rising to Rs. 1oco in five years by four annual increments of Rs. 50. Applications for the post must reach the undersigned on or before December 17, 1906. Candidates are required to send printed copies of their testimonials. Canvassing will be considered a disqualification.

The Registrar will be appointed in the first instance for five years only, but at the end of every such term he may be re-appointed. He must be a graduate of position with experience of University affairs. He may be a member of the Senate, but not of the Syndicate.

The duties of the Registrar will be as follows:

(a) To be the custodian of the Records, Library, Common Seal, and such other property of the University as the Syndicate will commit to his charge.

(b) To act as Secretary to the Syndicate and to attend all meetings of the Senate, Faculties, Syndicate, Boards of Studies, Board of Accounts, Boards of Examiners, and any Committees appointed by the Senate, the Faculties, the Syndicate, or any of the Boards, and to keep Minutes thereof.

() To conduct the official correspondence of the Syndicate and the
Senate.

(a) To issue all notices convening meetings of the Senate, Faculties,
Syndicate, Boards of Studies, Board of Accounts, Boards of
Examiners, and any Committees appointed by the Senate, the
Faculties, the Syndicate, or any of the Boards.

(e) To perform such other work as may be, from time to time, pre-
scribed by the Syndicate, and generally to render such assistance
as may be desired by the Vice-Chancellor in the performance
of his official duties.

It is competent to the Syndicate to grant to the Registrar, on full pay, leave of absence for one month in a year, or for an accumulated period not exceeding four months in five years. It is also competent to the Syndicate to grant him, on half pay, leave of absence which may be added to the period of leave on full pay for a period not exceeding eight months in five

years.

It is competent to the Syndicate to grant to the Registrar a gratuity or pension regulated as follows:

(a) After a service of less than ten years, a gratuity not exceeding one month's salary for each completed year of service.

(b) After a service of not less than ten years up to twenty-five years, a pension not exceeding one-sixtieth of the average salary (¿.e., the average calculated upon the last three years of service) multiplied by the number of years of completed service. (c) The pension will, in no case, exceed Rs. 5000 per annum. In case of misconduct or neglect of duty, the Registrar shall be liable to suspension by the Syndicate, and to dismissal by the Senate on the report of the Syndicate.

The selected candidate will be required to join his post by the middle of February, 1907. He will continue to hold office not later than March 31, C. LITTLE, Registrar.

1912.

Senate House,

September 7, 1906.

UNIVERSITY

COLLEGE OF SOUTH WALES AND MONMOUTHSHIRE, COLEG PRIFATHROFAOL DEHEUDIR CYMRU A MYNWY. The Council of the College invites applications for the post of DEMON. STRATOR and ASSISTANT LECTURER in GEOLOGY.

Further particulars may be obtained from the undersigned, to whom applications, with testimonials (which need not be printed), must be sent on or before Thursday, November 22, 1906.

OF EDINBURGH.

CALCUTTA UNIVERSITY.

NOTICE.

In January, 1907, the Senate will proceed to appoint a salaried INSPECTOR for the purpose of inspecting Colleges affiliated to this University. Applications for the post are hereby invited, and they must reach the undersigned on or before December 17, 1906. Candidates are required to send printed copies of their testimonials. Canvassing will be considered a disqualification. The appointment will be made by the Senate subject to the approval of Government.

The Inspector of Colleges will be appointed in the first instance for five years only, but at the end of every such term he may be re-appointed. He must be a person of high academic standing and one possessing some experience of Indian Colleges. He will be a whole-time officer of the University, and his salary will be Rs. 800 per mensem, rising to Rs. 1000 in five years by four annual increments of Rs. 50. He may be a Fellow of the University, but must not be a member of the Syndicate.

The duties of the Inspector of Colleges will be :-
(a) To report on Colleges applying for affiliation.
(b) To inspect affiliated Colleges, and

(c)

To inspect such Schools as may, from time to time, be indicated by the Syndicate.

It is competent to the Syndicate to grant to the Inspector of Colleges, on full pay, leave of absence for one month in a year, or for an accumulated period not exceeding four months in five years. It is also competent to the Syndicate to grant him, on half pay, leave of absence which may be added to the period of leave on full pay for a period not exceeding eight months in five years.

The Inspector of Colleges may, with the permission of the Syndicate, avail himself of the College vacations.

The Syndicate may grant to the Inspector of Colleges a gratuity or pension regulated as follows:

(a) After a service of less than ten years, a gratuity not exceeding one month's salary for each completed year of service.

(b)

After a service of not less than ten years, up to twenty-five years, a pension not exceeding one-sixtieth of the average salary (ie., the average calculated upon the last three years of service) multiplied by the number of years of completed service.

(c) The pension will, however, in no case, exceed Rs.5000 per annum. In case of misconduct or neglect of duty, the Inspector of Colleges will be liable to suspension by the Syndicate and to dismissal by the Senate on the report of the Syndicate.

The selected candidate will be required to join his appointment by the middle of February, 1907. He will continue to hold office not later than the Annual Meeting of the Senate in January, 1912.

Senate House,

C. LITTLE, Registrar.

September 7, 1906.
UNIVERSITY OF BIRMINGHAM.

ELECTRICAL ENGINEERING DEPARTMENT. Applications are invited for the post of SENIOR LECTURER and DEMONSTRATOR. Applicants must have had a University education, must have been engaged for at least three years in a responsible capacity with a first-class electrical engineering firm, and for at least one year in scientific laboratory and teaching work at a University or Technical College. Applicants must state age, course of study and practical experience, appointments held, and enclose copies of testimonials (not originals). If the applicant has published any scientific or technical papers, a list of these may be given.

The selected applicant will be required to act as the Professor's Assistant in preparing demonstrations, organising and supervising the laboratory work of the students, and generally attending to the technical work and the accounts of the Electrical Engineering Department under the direction of the Professor. He may also be required to give lectures.

The appointment to commence on January 1, 1907. The stipend to be £250 per annum.

Applications to be sent on or before November 24 to the undersigned, from whom further particulars may be obtained. GEO. H. MORLEY, Secretary.

College of Physicians of Edinburgh is vacant.

position will be received until November 1, 1006.

For information regarding duties and emolument apply to the SECRETARY, Royal College of Physicians, 9 Queen Street, Edinburgh.

good all-round metal and wood worker with experience of electrical machines and installation. Knowledge of glass blowing a recommend. ation.-Apply, stating wages, to "MECHANIC," c/o NATURE.

MASTERS.-Immediate and January (1907) Vacancies.-Graduates in Science and other well qualified Masters seeking posts in Public and other Schools should apply at once, giving full details as to qualifica. tions, &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.

DEWSBURY TECHNICAL SCHOOL. WANTED at once, an ASSISTANT SCIENCE MASTER to teach boys in Elementary Science, and to help in the Evening Classes (Chemistry and Physics). Must be a good disciplinarian. Salary, £100. Apply, with testimonials,, not later than Monday, October 29, 1906, to P. F. LEE, Secretary.

A Teacher of Experimental Physics required at once at the Woolwich Polytechnic. Experience of laboratory work essential. Remuneration until April, 1907, Lico.-Apply for further particulars to the PRINCIPAL, enclosing stamped addressed foolscap envelope.

old platinum crucibles, scrap, &c. 500 ozs. urgently needed during November.-R. OLPHERT, Jeweller, 19 Elm Grove Parade, Barnes, Surrey. Bankers: London, City and Midland (Barnes).

JUST PUBLISHED. Price 6s.

PARADOXES OF

NATURE AND SCIENCE

Things which appear to contradict general experience or scientific principles, with popular explanations of the how and why.

By W. HAMPSON, M.A. Oxon., L.S.A. Lond.

With 8 Full-page Plates and numerous other Illustrations. 6s. This is a book for popular reading; a book of puzzles drawn from nature and experiment, with the solutions given by science. The jinrikisha and the boomerang, the use of fire to produce water and of water to produce fire, a liquid that boils under 350 degrees of frost, a clock that never stops and never wants winding, evidence that the seeing eye is blind, and that the hand which feels the warmer is the colder-these and a hundred other apparent contradictions of commonsense and the laws of nature, have their difficulties clearly set forth, and receive explanations which, while strictly in accordance with the best and latest teaching, are intelligible to all.

CASSELL & CO., LTD., LONDON,

THURSDAY, OCTOBER 25, 1906.

THE GEOLOGICAL HISTORY OF SEA-LEVEL.

The Face of the Earth (Das Antlitz der Erde). By Prof. Eduard Suess. Translated by Dr. Hertha B. C. Sollas, under the direction of Prof. W. J. Sollas. Vol. ii. Pp. vi+556; illustrated. (Oxford: Clarendon Press, 1906.) Price 25s. net.

THE

HE first volume of this translation has been previously reviewed in NATURE, and we can renew our congratulations to the translator on her admirable rendering of this great work. Prof. Suess's eloquence depends on his ideas and his poetical imagery, and thus his writings suffer less by translation than those of most men. Doubt may be felt whether some of the proposed equivalents of technical terms, and such words as quer-Andian, will be generally adopted in English. In reading the volume it is necessary to remember that the original was published eighteen years ago. The French translation, edited by M. de Margerie, was brought up to date and illustrated by additional maps; but this edition exactly follows the original, and does not even add the date of its first publication. We are, however, frequently reminded of its age by such statements as that the Arctic Ocean is " of very trifling depth," or that the author cannot hazard a guess as to the structure of the Celebes. In many cases the facts stated are now known to be incorrect; but later research has removed Prof. Suess's difficulties probably more often than it has added to them.

The main purpose of this volume is the statement of the evidence for Suess's contention that continents are never uplifted in mass, and that the occurrence of raised shore lines and horizontal sheets of marine rocks is due to the lowering of sea-level, and not to the raising of the land. Suess, therefore, returns to pre-Playfairian geology, for Playfair maintained that the level of the land is less stable than that of the sea. This apparently improbable conclusion became, owing to the brilliant advocacy of Lyell, the fundamental principle of the Uniformitarian school of geology.

The contrary view was dismissed by Herbert Spencer as one of the gratuitous assumptions of what he called "illogical geology." Nevertheless, it is now advocated by the geologist who has probably the widest general acquaintance with geological literature, and is gifted with a scientific insight that has materially advanced each of the many branches of geology to which he has given his attention.

Prof. Suess's argument is that a continental uplift is impossible. A continent may subside, but it cannot be uplifted in mass. Rocks may be raised locally when uptilted during the formation of a mountain chain; but he denies the possibility of the uniform uplift of widespread masses composed of irregular materials. The sea has certainly encroached at times upon the land, and has at others receded; but instead of these changes being due to the sinking and rising of the land, Suess maintains that they are due to variations in sea-level,

That the sea-level is not uniform is indisputable.

It varies from causes which need only to be stated to be accepted. The water is heaped up in places by wind and rivers. Elsewhere it is lowered by rapid evaporation, and the surface is maintained at the lower level by the greater weight of the salter water. Thus the surface of the Mediterranean, according to Suess, is funnel-shaped, the lowest part of the funnel being in the area of especially salt water in the neigh

bourhood of Crete. Variations in wind and rainfall or in the course of rivers; the reduction in the lateral attraction of the land, in consequence of its denudation; the retardation of an on-shore current by increased friction. due to shoaling, may all lead to a local retreat of the sea. Thus Suess attributes a raised beach near Bombay to sedimentation having checked the incoming tide, and thus caused a local depression of sea-level. The apparent effect of these causes on the shore-line would be the same as that produced by an actual uplift of the land. As the retreat or advance of the shore-line may be produced by the oscillation either of the land or of the sea, Suess objects to the usual terminology, which always speaks of the uplift or subsidence of the land. To avoid unproved assumptions he speaks of negative and positive movements, according as the sea-level falls or rises relatively to the adjacent land. Sir Archibald Geikie has suggested terms-the emergence and submergence of the land-which are equally noncommittal, and have the advantage of being selfexplanatory. The encroachment or retreat of the sea may be a merely local incident or it may be a worldwide phenomenon; in the latter case, Suess speaks of it as a eustatic movement, and explains it as due to an increase or reduction in the capacity of the ocean basins. A negative movement, i.e. an emergence of the land, would be caused by an increase in the depth of the oceans by a subsidence of their floor, which lets the water fall away from the land.

This volume may be considered in two sections; in the first chapters Prof. Suess states his heterodox doctrine, and the mass of stratigraphical evidence in its support. In the second section he examines the leading cases relied on by the champions of secular elevation of the land. These two sections of the book appear of unequal value, for they deal with movements of probably different character and origin. The first part describes the great movements of emergence and submergence which are world-wide in their range; Suess's greatest service to geology has been his recognition of this fundamental fact and its consequences. It is a most helpful discovery, and Prof. Suess offers us the only reasonable explanation yet advanced. The evidence is summarised by Suess in chapters ii. to vi. of this volume. Therein he describes and compares in detail the coasts of the Atlantic and the Pacific, and gives a summary of the geological history of the oceans. The striking resemblance in the lithological succession in some of the geological systems in remote parts of the world can only be explained on the assumption that they are controlled by some world-wide agency; this, Suess's fundamental proposition, seems to be supported by the general evidence of stratigraphical geology.