A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE

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Of Nature trusts the mind which builds for aye.”—WORDSWORTH.

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SARDINIA ST., LONDON, W.C.

xliv

EAST LONDON TECHNICAL

COLLEGE,
MILE END ROAD, E.

TEACHING STAFF.
Mathematics

ŞJ. L. S. HATTON, M.A., and

W. F. S. CHURCHILL, M.A. Chemistry

J. T. Hewitt, D.Sc., and

1 C. SMITH, D.Sc. Mechanical Engineering... D. A. Low, M.I.M.E. Electrical Engineering

J. T. MORRIS, A.M.LE.E.

JR. A. LEHFELDT. D.Sc., and Physics

W. H. WAITE, B.A., B.Sc. Botany

V. H. BLACKMAN, M.A. The DAY CLASSES for students over 16 years of age include full three years' technical courses in Chemistry and Engineering, and three years' courses for London University Degrees (Pass and Honours).

EVENING CLASSES are held in Advanced Technical and Scientific subjects, and for London University Degrees.

Valuable SCHOLARSHIPS are awarded by the Drapers' Company in connection with the Day Classes. CALENDAR with full particulars post free, 4d.

J. L. S. HATTON, Director of Studies.

NORTHERN POLYTECHNIC

INSTITUTE,

HOLLOWAY, LONDON, N.
(Close to Holloway Stn., G.N. R., and Highbury Sın., N.L.R. I
LONDON UNIVERSITY SCIENCE AND ENGINEERING

DEGREES.
Day and Evening Courses in the above under recogoised teachers ia-
MATHEMATICS,

PHYSICS,
CHEMISTRY,

ENGINEERING.
Separate Laboratories for Elementary, Advanced and Honours students,
exceptionally large and well equipped.

RESEARCH.
Accommodation and apparatus provided for research in either Pure ou
Applied Chemistry and Physics, and Engineering, in rooms specially
adapted for this purpose,
Full particulars at the Institute or sent on receipt of postcard.

REG. S. CLAY, D.Sc., Principal.

COACHING (THEORY.CAND

SALOP COUNTY COUNCIL.

HIGHER EDUCATION. NOTICE IS HEREBY GIVEN that an EXAMINATION will be held in Shrewsbury early in January, 1905, to elect to an Exhibition for Science Subjects of the value of £50 per annum tenable for not more than three years, by Candidates who hold or bave held an open Scholarship or Exhibition at some University or College of University rank approved by the Salop Education Authority. The Exhibition is open to natives of Shropshire, and al:o to those who received their education within the County for the two years immediately preceding the time at wbich they joined the Institution in which they hold or have held their qualifying Scholarsbip. In awarding the Exhibition special regard will be bad to the need of qualifying Candidates for further pecuniary assistance. Entries, on forms to be obtained from the SECRETARY, Higher Education, Shireball, Shrewsbury, must be received by the undersigned not later than December 20, 1904.

W. H. PENDLEBURY, M.A.,
Shirehall, Shrewsbury,

Secretary for Higher Education.
November 28, 1904.
BEDFORD COLLEGE FOR WOMEN.

(UNIVERSITY OF LONDON.)

YORK PLACE, BAKER STREET, W.
The LENT TERM begins on THURSDAY, JANUARY 19, 1905.

The College provides instruction for Students preparing for the University of London Degrees in Arts, Science, and Preliminary Medicine, also instruction in subjects of General Education.

There is a Training Department for Teachers, a Hygiene Department, and an Art School.

Students can reside in the College.

Particulars on application to the PRINCIPAL.
BEDFORD COLLEGE FOR WOMEN.

(UNIVERSITY OF LONDON.)

YORK PLACE, BAKER STREET, W.
DEPARTMENT FOR PROFESSIONAL TRAINING IN

TEACHING
SCHOLARSHIPS FOR SECONDARY TRAINING.
Two Scholarships, each of the value of £10, will be offered in January,
1905. The Scholarships will be awarded to the best Candidates holding a
Degree, or equivalent, in Arts or Science.

Applications should be made not later than December 13, 1904, to the
HEAD OF THE TRAINING DEPARTMENT, Bedford College.
CIVIL SERVICE COMMISSION.

FORTHCOMING EXAMINATION.
ASSISTANT EXAMINERS IN THE PATENT OFFICE (20-25),

15711 DECEMBER.
The date specified is the latest at which applications can be received.
They must be made on forms to be obtained, with particulars, from the
SECRETARY, Civil Service Commission, Burlington Gardens, London, W.
GOVERNMENT GRANT to defray the

expenses of Scientific Investigations. Applications for the year 1905
must be received at the Offices of the Royal Society not later than
January 31 next, and must be made upon printed forins to be obtained
from the CLERK TO THE GOVERNMENT GRANT COMMITTEE, Royal

Society, Burlington House, London, W.
TO SCIENCE AND MATHEMATICAL
MASTERS:-

January (1905) Vacancies. -Required (1) Graduate for
Physics and Mathematics. 6140 to $180. (2) Mathematics and
Science. [130. County School, London. (3) Science Master for
County School near London--- Botany chief subject. 6140 Drim-
mence (4) Science and Drawing. £150. (5) Chemistry and Phy in
£100, resident. (0) Graduate for Science and Form work. Liuo,
resident. For particulars of the above and many other vacancies,
address GRIFFITHS, SMITH, POWELL & Smith, Tutorial Agents (bstd.
1833), 34 Bedford Street, Strand, London.

)
In BIOLOGY, BOTANY, CHEMISTRY and PHYSIOLOGY
MEDICAL EXAMS.

Especial Course of Instruction in THERAPEUTICS, PHARMA.
COLOGY and MICROSCOPY for INSTITUTE OF CHEMISTRY
EXAM.

Mr. FREDERICK DAVIS, The Laboratories,
(Registered in Column 8 (Advanced Education). Teachers Registration

Council, Board of Education, S.W.),
49 and 51 IMPERIAL BUILDINGS, LUDGATE CIRCUS, E.C.
WANDSWORTH TECHNICAL

INSTITUTE.

Geo. F. GOODCHILD, Principal.
DIPLOMA IN EDUCATION FOR SECONDARY TEACHERS.

A Class for Teachers preparing for the London University Diploma for
Teachers will commence on Monday, December 5, at 8 p.m. Full detail
of the Course may be obtained at the Institute, or free by post.
GLAMORGAN COUNTY COUNCIL,

EDUCATION COMMITTEE.

PHYSICAL INSTRUCTOR.
The Education Committee desire to appoint a TRAVELLING IN.
STRUCTOR, who must be a Trained Gymnast, to teach PHYSICAL
EXERCISES, GYMNASTICS and DRILL in County Schools.

The whole time of the person appointed shall be devoted to the service of the County Council, and he shall reside where directed by them.

Salary, £140 per annum, advancing by £10 a year to 6170, with Travel. ling Expenses,

Applications, accompanied by a statement of the system or systers candidates are qualified to teach, their previous teaching experience and ages, together with copies of their Diplomas and of not more than three recent testimonials, must reach the undersigned not later than December 7. 1904. Personal canvassing will be deemed a disqualification.

JOHN JAMES, M.A., Ph.D.,

Chief Education Official.
Education Department, Westgate Street, Carditi,

November 22, 1904.
COUNTY BOROUGH OF WEST HAM.

MUNICIPAL TECHNICAL INSTITUTE.
The Council invite applications for the following post on the Teaching
Staff of the Institute :-

DEMONSTRATOR in MECHANICAL ENGINEERING. Salary, £150 per annum

Canüidates must bave read the Circular giving particulars of the daties attached to the post, copies of which may be obtained by sending a fully addressed envelope to the PRINCIPAL, Municipal Technical Institute, West Ham, E.

All applications must be lodged with the PRINCIPAL before non, December 5, 1904.

By Order of the Council,

FRED, E. HILLEARY, Town Clerk
Education Department, West Ham. E.
WEST MONMOUTHSHIRE SCHOOL,

PONTYPOOL.
ASSISTANT MASTERS wanted for January next.

Science and
Mathematics, £150; Forin Master, 120.
Applications to be sent to the HEAD MASTER.

For other Scholastic Advertisements, see page xlv.

1

BROWNING'S MICRO-CAMERAS.

MICROSCOPE TUBE

CREWKERNE SCHOOL, SOMERSET.

The Governing Body invite applications for the HEAD MASTERSHIP of the above mentioned Public Secondary School for Boys. The school will, by the scheme under which it will be regulated, be conducted as a Public Secondary School working in accordance with the regulations of the Hoard of Education with a view to receiving Grants from the Board of Fducation and the Somerset County Council. Salary, £200 per annum, together with an annual Capitation Fee of £2 per pupil (which are guarantee 1 for three years) and residence.

(MICROKAM-Regd.) Permission to receive Boarders at a charge of £25 exclusive of Tuition Fees (£61 and £2 for books, games, drill, and swimming bath.

A simple yet perfect Instru.

ment for Photographing Accommodation for 120 pupils, including 45 boarders. Applicants must be University Graduates and registered on Col. B. of

Objects under the Microthe Teacbers' Register, or hold equivalent qualifications.

scope. Rxperience in a large school essential.

No. 1.-Mahogany, 5s. The appointment to date from the close of the Easter Holidays, 1905.

No. 2.- Do., with Focussing Applications, with copies of not less than three recent testimonials, should

Screen and Double Dark be vent not later than December 13 to the undersigned, from whom further

Slide

16s. 6d. information can be obtained.

Do. do. (31 square) 31s. 6d. JOHN SPARKS, Solicitor, Crewkerne,

Adapt ng ei her to fit MicroNovember 26, 1904. Clerk to the Governors.

scope ...

9d.

Brass Adapter, do. 3s. 6. STAFFORDSHIRE COUNTY COUNCIL.

EDUCATION COMMITTEE.

SCIENCE APPLIED TO POTTERY. WANTED, a PHYSICAL SCIENTIST with first-class University qualifications in Chemistry as Instructor to the County Pottery Classes in North Stafiordshire. Salary: 6350 per annum (with prospects of future developments in connection with the proposed North Staffordshire College). Private practice allowed under conditions. Any form of canvassing will disqualify.

Forms of application must be returned not later than December 17, and can be obtained, together with a Schedule of Conditions, from

GRAHAM BALFOUR, M.A.
County Education Offices, Stafford,
November 28, 1904.

Science Gossip says :—“From a personal experience we can vouch
TECHNICAL COLLEGE,

for the fact that it is capable of doing fairly critical work, and it

is therefore specially suitable for students in the photographing SUNDERLAND,

of botanical, entomolo; cal and histological speciniers.”

K'nowledge (Microscopical Editor) says :-"I have seen this class LECTURESHIP IN MECHANICAL AND CIVIL

of camera used by ardent photographers who have wished to ENGINEERING.

secure a photograph of a unique or interesting specimen." Owing to the appointment of Dr. Smith, the present Lecturer, to the Lectureship in Engineering at the Municipal Technical Institute, Belfast, JOHN BROWNING, Manufacturing Optician, applications are invited for the above post. Salary, 6300 per annum ; no fees Age not to exceed forty years. The standard of the teaching is that 78 STRAND, LONDON, W.C. of a University College, and candidates must therefore be qualified to give instruction of this standard. Applications, with a duplicate set of not more than three testimonials, to reach the undersigned at the College not later than December 11, 1904. Apply for further particulars to

A
BENCHARA BRANFORD, Principal.
November 29, 1904

UNIVERSITY OF LONDON.
The SENATE invite applications for the post of WARDEN of the
GOLDSMITHS COLLEGE, New Cross, at a salary of £150 per annum.
The Warden of the College will also act as head of the Training College to

makes an acceptable
be opened in October, 1905. Applications, accompanied by thirty copies of
Dot more than five testimonials, must reach the University not later than
December 20. 1904, and should be addressed to the PRINCIPAL, University
of loodon, South Kensington, S.W., from whom further particulars may be
obtained.
ARTHUR W. RÜCKER, Principal.

To ensure prompt delivery Orders SCIENCE AND MATHEMATICAL

should be booked at once. MASTERSHIPS VACANT. Science Public College, £200; North England. Chemistry and Physics, 6175. Mathematics and Chemistry. Ireland, £150. Chemistry, £120. Mathematical, 6180. A list of Masterships, England, Continent, and Over Sea, sent to all Candi. dates.- ORELLANA & Co., Est. over 40 years, 80 Wigmore Street, Cavendish Square, London, W. (late 44 Old Bond Street, W.).

SANGER - SHEPHERD

COLOUR OUTFIT

CHRISTMAS GIFT.

SCIENCE AND MATHEMATICAL MASTERS. Messrs. NEEDES & SELLICKS,

(Medical and SCHOLASTIC Agency, Estab. 1860), Clock House, Arundel Street, Strand, W.C. Applications are invited for the following appts. :-(1) Public Sch., Nat. Sc and Drawg., £150+ fees; valuable post to good man. (2) Chem. and Physics little English. Games preferred. £120, res. (3) Chem. + Magteusm and Elecıricity. €100, res. (4) Wrangler, Public School. 6110, res. (9) County School, Maths. £110, non-res. Many January Appointments.

Complete Outfits to attach to Plate Cameras, including
Repeating-Back as above, and every requisite,

from £7 10 0
Send for New Booklets, post free to readers of Nature,"

or call and see results ohtained by amateurs.

SCIENCE MASTER Wanted for Cape

Colony in February. Large Public School. Unmarried man and churchmuan required. £150, resident. Free passage. Testimonials must accompany enquiries. Apply to Professor Lewis, Cambridge.

SANGER-SHEPHERD & CO.,

5, 6 & 7, Gray's Inn Passage, Red Lion St., Holborn, London, W.C.

For other Scholastic Advertisements, see page xliv.

LIQUID AIR AND LIQUID HYDROGEN. RECTIFIED SPIRIT

(SPIRITS OF WINE). B.P. and higher strengths. Duty paid; or Duty

Free 'under Finance Act 1902.

Dr. HAMPSON'S AIR-LIQUEFIER is now made to a standard pat. tern, and aumbers are in use in University Laboratories and elsewhere in various countries. The whole apparatus is neat and compact and its parts very easily moved ; the Liquefier, without stand, being a cylinder 19 inches high and 8 inches in diameter.

It begins to liquefy air in from 6 to 10 minutes after the admission of air at from 150 to 200 atmospheres pressure, making over a litre of liquid per hour.

It requires no auxiliary refrigerant and produces a perfectly clear liquid which requires no filtering.

The operator bas only one gauge to watch and one valve to control. HYDROGEN LIQUEFIER to the designs of Dr. MORRIS W. TRAVERS for use in conjunction with Air-Liquefier.

METHYLATED SPIRIT

Special Quotations to large

Institutions.

For Prices and Particulars apply to the Sole Makers :BRIN'S OXYGEN COMPANY, LIMITED,

ELVERTON STREET, WESTMINSTER, S.W.

BOORD & SON,

DISTILLERS SINCE 1730,
15-121 Tooley Street,

LONDON, S.E.

MACMILLAN & CO.'S LIST.

VOLUME VII. NOW READY.

THE CAMBRIDGE NATURAL HISTORY.

EDITED BY S. F. HARMER, Sc.D., F.R.S., AND A. E. SHIPLEY, M.A., F.R.S.
TO BE COMPLETED IN TEN VOLUMES. FULLY ILLUSTRATED. 8vo. PRICE 175. NET EACH.

VOLUME VII. FISHES, &c.
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Account of Teleostei). By G. A. BOULENGER, F.R.S. HEMICHORDATA, By S. F. HARMER, Sc.D., F.R.S.
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PREVIOUSLY PUBLISHED.
WORMS, LEECHES, &c.

INSECTS. PART II.
VOLUME II.

VOLUME VI.
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tera, Strepsiptera, Lepidoptera, Diptera, Aphanip. SHIPLEY, M.A., F.R.S. Rotifers. By Marcus HARTOG,

tera, Thysanoptera, Hemiptera, Anoplura. By M. A. Polychaet Worms. By W. BLAXLAND BENHAM, DAVID SHARP, M.A., F.R.S. D.Sc. Earthworms and Leeches. By F. E. Bed. DARD, M.A., F.R.S. Gephyrea, &c. By A. E. AMPHIBIA &3 REPTILES. Shipley, M.A., F.R.S. Polyzoa. By S. F. HARMER,

VOLUME VIII.
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By HANS Gadow, M.A., F.R.S.
SHELLS.
VOLUME III.

BIRDS.

VOLUME IX. Molluscs and Brachiopods. By the Rev. A. H. COOKE,

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LODGE.
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MAMMALIA.
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VOLUME X.
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SECOND EDITION NOW READY. THE PRINCIPLES OF INORGANIC CHEMISTRY. By WILHELM OSTWALI).

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Latin Spelling. By W. II. D. Rouse, M. A., Litt.D.-The Teaching of Dynamics in Schools. By PROF. G. M.
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