NOTICE.

NATURE

Of THURSDAY NEXT, JUNE 8, will contain the
INDEX TO VOL. LXXI.

ITS PRICE WILL BE ONE SHILLING. Advertisements intended for this number should reach the Publishers by Tuesday, June 6.

OFFICE OF "NATURE,"

ST. MARTIN'S STREET, LONDON, WC.

BY ORDER OF THE SECRETARY OF STATE FOR INDIA IN COUNCIL.

India Office,

Whitehall, S.W.,

May 23, 1905.

WANTED, for service at the India Store Depôt, Belvedere Road, Lambeth, London, S.E., an ASSISTANT INSPECTOR OF SCIEN. TIFIC SUPPLIES.

Candidates must have a knowledge of optical work as applied to survey. ing and similar instruments, and of balances as used for chemical, assay, and mint purposes. They must also have a thorough knowledge of physics and be acquainted with the general principles of electricity.

Age, 25 to 30. Salary, L200 per annum, rising by annual increments of 10, on satisfactory report, to £350 per annum. Pension under Civil Service Regulations.

The selected candidate will be examined by the Medical Board at the India Office, and will only be appointed if passed by the Board.

Forms of application can be obtained by writing to the Director General of Stores, India Office, Whitehall, London, S. W., not later than June 5,

1905.

BEDFORD COLLEGE

E. GRANT BURLS, Director General of Stores.

FOR WOMEN.

(UNIVERSITY OF LONDON.)

YORK PLACE, BAKER STREET, LONDON, W.

A Reid Scholarship in Arts, annual value £31 10s. first year, £28 75. second and third years, and an Arnott Scholarship in Science, annual value £48, both tenable for three years, will be awarded on the results of an examination to be held at the College on June 28 and 29. For further information apply to the PRINCIPAL.

DEPARTMENT FOR PROFESSIONAL TRAINING IN
TEACHING.

Students are admitted to the Training Course in October and January. Two Scholarships, each of the value of £10, will be awarded for the course of Secondary Training beginning in October, 1905. Applications should reach the HEAD OF THE TRAINING DEPARTMENT not later than July 7, 1905.

HARTLEY UNIVERSITY COLLEGE, SOUTHAMPTON.

Principal-S. W. RICHARDSON, D.Sc., B.A.

A SUMMER COURSE OF BOTANY, for Teachers and others, will be held at the above College, July 31 to August 13, 1905. This course, which will consist chiefly of practical work in the Botanical Laboratory of the College with field-excursions, will be conducted by Professor CAVERS, D.Sc. (Lond.), F.L.S.

Fee for the course, 155., payable in advance to the Registrar of the College, Mr. D. KIDDIE, from whom full particulars may be obtained on

DEPARTMENT FOR THE TRAINING OF TEACHERS.

In view of the opening of the above Department in the latter part of September next, TEACHERS (Men and Women) of the various subjects included in the Scheme of Studies will shortly be appointed.

The Scheme includes both General Education and Professional Instruction.

The majority of the salaries will be between £150 and £250 a year, but higher or lower salaries may be paid in exceptional cases.

Applications must be received not later than Saturday, June 17, 1905. Particulars may be obtained from the WARDEN, Goldsmiths' College, New Cross, S.E.

BIRKBECK COLLEGE.

The Council invite applications for the appointment of ASSISTANT LECTURER IN MATHEMATICS. Commencing Salary £175, to date from September 1 next. Applications, stating age, degrees and qualifications, teaching experience, and enclosing testimonials, must reach the PRINCIPAL not later than Tuesday, June 20.

Birkbeck College,

Breams Buildings, Chancery Lane, E.C.

BOROUGH OF LEICESTER-EDUCATION

COMMITTEE.

MUNICIPAL TECHNICAL SCHOOL. ASSISTANT INSTRUCTOR in ENGINEERING wanted for Sep. tember 1, to teach chiefly Applied Mechanics and Machine Construction and Drawing-Day and Evening Classes. Salary, 150 per annum. Applications, accompanied by copies of recent testimonials, to be sent to Education Department, T. GROVES, Secretary.

Town Hall, Leicester,

May 24, 1905.

TO SCIENCE AND MATHEMATICAL MASTERS.-September (1955) Vacancies.-Graduates and other well qualified Masters seeking posts in Public and other Schools for next term should apply at once, giving full details as to qualifications, &c., to Messrs. GRIFFITHS, SMITH, POWELL & SMITH, Tutorial Agen's (Est. 1833), 34 Bedford Street, Strand, London. Immediate notice of all the best vacancies will be sent.

MEERUT COLLEGE.

(NORTHERN INDIA.)

Applications are invited for the FIRST (European) PROFESSORSHIP (PHYSICS). Salary, £320 per annum (50 passage money). Candidates should be University Graduates, under 5 years of age, and unmarried

THE VICTORIA

UNIVERSITY OF MANCHESTER

AND

MANCHESTER ROYAL INFIRMARY.

ENTRANCE MEDICAL SCHOLARSHIPS.

Two Scholarships will be offered, one for proficiency in Arts and one for proficiency in Science.

Each Scholarship is of the value of £100, and the successful candidates will be required to enter for the full medical curriculum both in the University and in the Manchester Royal Infirmary.

The Scholarships will be awarded only to candidates who give evidence of a high standard of proficiency in Arts and Science respectively.. Applications should be sent in on or before July 1, 1905, to the REGISTRAR, from whom further particulars may be obtained.

A LECTURER AND DEMONSTRATOR required in the Chemical Department. Salary commencing at £130, and rising by £10 per annum to £18 Applications to be sent in by June 30 addressed to the REGISTRAR, from whom application forms and particulars as to duties, &c., may be obtained.

UNIVERSITY COLLEGE, BRISTOL.

The Council invite applications for the post of LECTURER in BOTANY. Salary, 120 per annum. Applications and three copies of three recent testimonials to be sent in by June 16 to the undersigned, from whom further particulars may be obtained.

To SCIENCE & MATHL. MISTRESSES. -Required (1) Mistress for Advanced Physics, some Maths. and Chemistry. Salary, £120, non-res. High school. (2) Elem. Physics, Chemistry, Botany, and Maths. 110. Important school in London. (3) Graduate for Botany and Chemistry. 6o, resident. (4) Botany and Elem. Physics. 65, resident. County school. (5) Science Mistress for important Girls' Grammar School. Graduate preferred. Fair Salary.-For particulars of the above, address, giving full details as to qualifications, &c., GRIFFITHS, SMITH, POWELL, & SMITH, Educational Agents (Estd. 1833), 34 Bedford Street, Strand. Many other vacancies for Science and other mistresses.

Research.

PHOTOMICROGRAPHIC

AND

LARGE
INDUCTION
COILS FOR
RESEARCH
WORK
a Speciality.

Also MANUFACTURERS of

X-RAY and HIGH-FREQUENCY APPARATUS of various patterns. LIGHT BATHS of all kinds, Cabinet, Reclining, Portable Baths, with three-colour arrangements, with Incandescent and Arc Lamps, &c., with Arc-Light Projector for simultaneous local treatment. (Combined Patent.)

NEW PATENT SHENTON-SANITAS X-RAY COMBINATION OPERATING TABLE.

"TRIPLET" and "DERMO" LAMPS with Carbon and Iron Electrodes for "Finsen Treatment.

VIBRATORY AND PNEUMATIC MASSAGE APPARATUS. APPARATUS FOR 3-PHASE SINUSOIDAL AND ALL OTHER CURRENTS.

NEW PORTABLE CAUTERY TRANSFORMER, with Terminals for Light, &c., taking only 2 Ampères from 200 Volts Continuous Main. MULTINEBULIZER, ELECTRO-MAGNETIC AND SWEDISH EXERCISE APPARATUS, &c., &c.

33 & 7a, SOHO SQUARE, LONDON, W.

PROJECTION APPARATUS.

Write for Illustrated Catalogue "Mn" post free on application.

ISSUED TO MARK THE

FIFTY YEARS' EXISTENCE OF THE FIRM

OF

E. LEYBOLD'S NACHFOLGER,

COLOGNE,

Contains on its more than 900 pages a complete survey of the apparatus used for instruction in Physics, as well as numerous practical instructions and about 3000 illustrations.

NATURE says: "The firm of Leybold Nachfolger in Cologne has recently issued a very complete and interesting catalogue of physical apparatus and fittings sold by them The book starts with a history of the instruments made in Cologne during the last century. In its second section we find an account of the construction and fittings of various chemical and physical institutions. After this follows the catalogue proper, filling some 800 large pages, profusely illustrated and admirably arranged. The book will be most useful to the teacher." (No. 1846, Vol. 71.)

THE

HE official responsibility for the safeguarding of the public health rests mainly with the representatives of four professions, viz. the medical officer, with his colleague the sanitary inspector, the bacteriologist, the engineer, and the chemist. A study of the volumes under review has strengthened the belief that it is desirable that members of each profession, while working cordially together for a common end, should severally recognise their respective limitations. The text-book on "Sanitary Law and Practice" by Drs. Robertson and Porter is written in sections, each section referring to some special branch of public health work. A considerable portion of each section is occupied by a digest of the legal enactments affecting the subject, this being followed by paragraphs dealing, by description and advice, with the practical duties of the health officer. The condensation of legal information, so far as can be estimated by references to special points coming under the experience of the reviewer, is done with judgment, and constitutes a feature of the book, of great value alike to the student and to the practitioner.

Many useful hints from the wide experience of the authors are to be found in the descriptive portions of the book. Their experience, however, is naturally not all-embracing, and it is not difficult to note where their information is derived from the statements of others.

The subject of destructors, although coming within the province of the engineer, is evidently one with which the authors are familiar. The descriptions are clearly written, and the essential points in construction, choice of site, and proper management well brought out.

In the section on food and drugs no attempt is made to instruct the medical officer in duties which properly belong to the public analyst. This is satisfactory in view of the attempt frequently made by ml authorities to combine the offices of public analyst and medical officer. Even in such a comparatively simple matter as the analysis of a sample of water, which in the chapter on water supply (p. 433) is referred to as part of the medical officer's

duties, unsuspected pitfalls may lurk. It is doubtful whether bacteriological examinations should ever be undertaken by any but a trained bacteriologist, at any rate where identification of a given species is required.

The

In the section on disinfection a questionable authors themselves, in a later paragraph, deprecate prominence is given to the use of sulphur. the use of superheated steam as being "no better than a gas," and in view of the obvious disadvantages in the use of sulphur, which have given rise to serious complaint of destruction of fabrics and fittings, especially on board ship, it can hardly be compared with liquid disinfectants such as formalin. No reference is made to the use of hypochlorites, which in certain circumstances have been found to give excellent results.

A wise reserve is maintained on the vexed question of sewer ventilation, a qualified approval being given to upcast shafts. It is unfortunate that a similar reserve has not been exercised in the chapter on sewage purification. In a book intended for students it is unwise to select, even for description, any form of patented appliance which is not thoroughly established. The choice for special commendation of one particular patented apparatus, concerning the merits of which competent opinion can at least be said to be divided, is certainly to be deprecated. A clear exposition of general principles of sewage treatment would have been more valuable.

This leads to the consideration of the able condensation of the bulky volumes of evidence given before the Royal Commission on Sewage Disposal which is to be found in Mr. Martin's book on the Sewage Problem." Mr. Martin has provided a book which will be eagerly sought after by members of sewage committees and others who are appalled at the mass of matter in the numerous blue-books

66

published by the commission. He is to be congratu lated upon the impartial way in which he has marshalled the evidence. Possibly because of this im partiality the impression left upon the reader is that in spite of the great amount of work that has been done on the subject, sewage purification is still rather an art than a science.

The Royal Commission has been criticised for the slowness of its methods. A more just criticism would be that it might have devoted more energy to questions affecting the theory of the processes in use. As it is, a mass of empirical and sometimes conflicting information has been accumulated, from which it is extremely difficult to extract underlying certainties. While fully realising that a large part of the sewage problem is concerned with purely practical questions of cost and local conditions, yet ultimately the economic solution must depend on a full knowledge of the changes taking place in the course of various methods of treatment; and these are as yet by no means perfectly understood. It is curious, e.g., that no witness deals in any detail with the purely physical effects produced by contact with the filtering medium, although many observers, especially on the Continent, believe that these play a very large part in connection with the changes produced. It is by no means