ADVANTAGES OF AN ALL-ELECTRIC HOUSE. The manifold advantages of the allelectric house will probably appeal chiefly to people whose habits are not inflexible and to innumerable small households where coal merely means drudgery. As regards cost, with energy not exceeding Id. or even 1d. per unit,overall, it would seem to be feasible to work large, medium, or small houses electrically, though the cost of installation may remain a difficulty. Fortunately, this matter seems now to be receiving the sympathetic attention of supply undertakings, and it may therefore be not too presumptuous to look forward to a time. in the near future when the full advantages of electricity in the home will be available to all. Among the advantages associated with electricity, cleanliness and health may well be emphasised. The absence of coal fires in a house like the one just described may make it possible to dispense with one domestic servant and thereby not only more than repay the total cost of the electrical energy, but also lighten the domestic labour problem. Equally, the improved health of the household and of the community, by eliminating smoke, is an inestimable benefit. Again, the rational mode of distributing and controlling heat is a great boon. Internal decorations seldom need renewal; cut flowers may last a month or even longer. Nuemrous minor luxuries become normal comforts and conveniences.

The Power Losses in Magnetic Sheet Material at High Flux Densities, by C. E. WEBB, B.Sc. (Eng.), Associate Member. (From the National Physical Laboratory.)

From an examination of the results of a number of investigations it is shown that while there is general agreement as to the validity of Steinmetz's expression B, where x is a constant index, for the hystere sis loss at flux densities up to about 10,000 C.G.S. units, there are considerable divergences between the results of different experimenters at flux densities above that value, particularly in tests on sheet material. Some find Steinmetz's law to apply closely up to the highest flux densities at which tests could be carried out, whilst others record more rapid variations of hysteresis losses with B in the region of B = 10,000-16,000. the extent of the departure from Steinmetz's law also varies considerably, some observers finding a maximum exponent of approximately 2.0

and others obtaining values as high as 3.2. In the paper a series of tests, both by a.c. and ballistic methods, on a wide range of sheet materials is described. The results of this appear to confirm the increase in the exponent of B in the expression for the hysteresis loss at values of B between 10,000 and 15,000. They also show comparatively little difference between the various specimens of sheet material tested.

The construction of a new Lloyd square for tests at still higher flux densities, and a further, more detailed, series of tests, both a.c. and ballistic, on a representative specimen of each type of material, making use of this square, are then described. These tests were carried up to B = 17,000 or 18,000, and, while confirming and extending the previous results of increased exponents of B for values up to 16,000, indicate a rapid decrease in the exponent at the highest values of B employed.

ROYAL INSTITUTION.

The lecture arrangements at the Royal Institution before Easter next year were announced at the general meeting of the Members on December 7.

The Juvenile lectures, the 100th course, will be delivered by Sir William Bragg, on "Old Trades and New Knowledge," commencing on December 29, at 3 o'clock.

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On Tuesdays, at 5.15, beginning on January 19, there will be two lectures by Dr. J. A. Crowther, on X-rays and Living Matter"; two by Dr. E. K. Rideal on "Surface Action "; four by Professor Barcroft on "The Egg "; and two by Dr. C. H. Desch, on "The Growth of Crystals.' On Thursday, Janhary 21, at the same hour, Dr. C. J. Patten will give the first of two lectures on (1) "The Language of Birds, (2) "The Breeding Factor in Birds." These will be followed by three lectures by Dr. J. L. Myres on Who were the Greeks?"; three by Dr. C. D. Ellis, The Atom of Light and the Atom of Electricity"; two by Dr. J. Holland Rose on "The Indecisiveness of Modern Warfare."

on

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On Saturday afternoons, at three o'clock, Mr. Henry Balfour will give two lectures commencing on January 23, on (1) "The Evolution of Currency and Coinage," (2) "The British Coracle, or the Skin-Covered Boat and its Affinities."

On succeeding Saturday afternoons there

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will be two lectures on The Nature and History of the Triad and the Perfect Fourth," by Sir Walford Davies, with musical illustrations; two by Dr. George Macdonald on "Roman Britain "; and four by Sir Ernest Rutherford on "The Rare Gases of the Atmosphere and their Importance in Atomic Theory."

The Friday evening meetings will begin on January 22, when Sir William Bragg will deliver a discourse on "The Work of the Davy Faraday Research Laboratory." Succeeding discourses will probably be given by Sir William Hardy, Professor Robert Robinson, the Hon. J. W. Fortescue, Dr. C. Hagberg Wright, Sir J. J. Thomson, Mr. John Tweed, Sir Ernest Rutherford, and other gentlemen.

A general meeting of the Members of the Royal Institution was held on December 7. Sir James Crichton-Browne, treasurer and Vice-President presided.

The special thanks of the Members were returned to Dr. W. Rushton Parker for his donation of £100 towards the improvement of the Library.

Mr. W. G. Bruty, Dr. P. C. Buck, Mr. J. R. Cousins, Mr. J. Scott Duckers, Mr. A. Edmunts, Mr. M. A. Greig, Mr. E. Marsden, Mrs. Murray, Lieut.-Col. B. C. Quill, Mr. A. L. Reckitt, Miss E. M. Stear, Mr. J. A. Stevenson, and Mr. H. B. Gordon Warren were elected Members.

THE PHYSICAL SOCIETY OF LONDON. Proceedings at the meeting held on Friday, November 27, 1925, at the Imperial College of Science, F. E. Smith, C.B.E., F.R.S., President, in the chair.

Atomic Dimensions, by R. G. LUNNON, M.A., M.Sc., was taken as read in the absence of the author.

The paper deals with the diameters of the atoms of the elements, and compares the estimates obtained by various methods -viz., (1) Atomic volumes; (2) X-ray analysis; (3) Viscosity of gases; (4) Van der Waal's equation and its modifications; (5) Compressibility; (6) Viscosity of liquids; (7) Viscosity of solutions; (8) Diffusion of ions; (9) Mobility of ions in solutions; (10) Latent heat of solution; (11) Speculations as to atomic laws of force; (12) Scattering of X-rays; (13) Bohr's theory in the case of the hydrogen atom; (14) Ionisation potentials; Band spectra; (16) Chemical constant; (17) Optical rotation; (18) Molecular films;

(15)

(19) Langevin's theory of diamagnetism; (20) Impacts of a stream of electrons on gas molecules; (21) Density changes in permutite; (22) Melting points of solids.

The results obtained by these methods, of which an extensive bibliography is given, are fairly accordant, and their mean shows that the addition of an inner electron shell gives an increase in diameter of roughly 0.5A.

Edge Tones, by W. E. BENTON, B.Sc., University of Birmingham.

An edge-tone is heard when a stream of air issuing from a slit or hole strikes on a sharp edge, or surface bounded by sharp edges. A brief description is given of previous work, and it is shown that the eddies which give rise to edge-tones conform to a simple Kármán vortex-system. On the assumptions (1) that the distance a from the edge to the slit is always equal to 1, the distance between two eddies in the same row, and (2) that tone is destroyed when the edge when moved across the jet towards still air-crosses the line of eddy centres, one can measure h/l, where his the separation of the eddy-rows, directly from measurements of the boundaries for tone. From the experiments it is found that at low pressures and with wide slits h/l, for air, 0.276, which may be compared with V. Kármán's prediction of 0.283 for an infinite system in a perfect fluid.

=

If the edge is moved towards the slit, h, the separation of the eddy-rows, must decrease proportionally. The experiments show that whn the eddies are formed very close to the edges of the slit, and therefore in a field of high velocity-gradient at right angles to the direction of motion, they are deflected towards the middle, or principal, plane of the jet. The amount of this deflection increases very rapidly as a ap、 proaches a, at which distance tone can only be obtained when the edge lies in the principal plane. The experiments show that with wide slits, when a = a,, then = ao h 0.67d, where d is the width of the slit. The minimum distance for tone a varies with the velocity v, and the width of the slit.

=

and is the coefficient of kinematic viscosity. By considering the acceleration that produces the deflection, an expression of somewhat similar form can be obtained theoretically. The tonal boundaries in the region of simple tone approach two straightline asymptotes, equally inclined to the principal plane, which converge at a point O near the plane of the slit. If á and á denote the distance of the edge and the minimum distance for tone respectively from 0, the total separation, y of the two boundaries at any listance á is given by the equation :--

where /m is approximately equal to d, when the slit is very wide. The measurements of the frequency of the tone and the deductions made from them will form the subject of a subsequent communication.

Curve of Bodies Falling from a Great Height. A demonstration of "An Instrument for Imitating the Eastward Deviation of Bodies Falling from a Great Height,' was given by Mr. G. R. Mather.

If a body, initially stationary with respect to the earth, be allowed to drop from a height, it will appear to move eastward as it falls. Newton suggested that this phenomenon might possibly furnish a measure of the earth's rate of rotation, and a photograph of his autograph letter on this subject was shown. The curve showing, the trajectory with respect to the earth, as drawn by Newton, was convex to the radius vector drawn to the initial position; and Professor Rankine, in introducing the demonstration, gave an analysis showing that this drawing is correct. Many astronomical text-books, however, give the curve as a parabola concave to the initial radius vector, and the apparatus is designed to show the true state of the case.

The apparatus comprises a large horizontal rotatable table on which a sheet of paper is mounted. A weight carrying a tracing point is designed to slide easily over the paper and is attached to a thread which passes down through a hole at the centre of the turn-table; a second weight is fastened to the other end of the thread, and hangs vertically below the turntable. The table is set in rotation by a gravity motor comprising a weight attached to a string,

which is wound round the spindle, and when the motor has gone out of action, so that the speed of rotation is constant, the thread is automatically cut, so that the tracer-weight may be drawn in towards the centre from its initially peripheral position. The curve traced is very similar to that sketched by Newton.

The demonstration acquired a personal interest from the fact that Mr. Mather, who is now 85 years of age, became interested in the subject at the age of 14 through an accident which befell him when playing with a joy wheel improvised from farm machinery.

SOCIETY OF PUBLIC ANALYSTS AND OTHER ANALYTICAL CHEMISTS. An ordinary meeting of the Society was held at the Chemical Society's Rooms, Burlington House, on Wednesday, December 2, 1925, Mr. S. F. Burford, Vice-President, was in the chair.

Certificates were read for the first time in favour of Messrs. Guy Chignell, K. Saito, and Hugh Gower Watts.

Certificates were read for the second time in favour of Messrs. John Douglas Barrett, B.Sc., A.I.C.; Arthur Frank Lerrigo, B.Sc., F.I.C.; Oscar Adolf Mendelsorn, B.Cc.; Harold Edward Monk, B.Sc., A.I.C.; and Eric Voelcker, A.R.C.S.

The following were elected Members of the Society-Messrs. Alexander Bruce, B.Sc., F.I.C.; Sydney George Clarke, B.Sc., A.I.C.; Felix John Theodore Grigg, M.Sc., A.I.C.; John John Hanley, F.I.C.; Arthur John Jones, A.I.C.; Henry William Lawrence, F.I.C.; Fred Mattingley, B.Sc., A.I.C.; Clive Newcomb, I.M.S., M.D., F.I.C.; Bartle Frere Sawbridge, M.A., F.I.C.; Harold Jacob Stern, B.Sc., Ph.D., A.I.C.

The following papers were read and

discussed:

Measuring the Smoke Pollution of City Air, by J. S. OWENS, M.D., A.M.I.C.E.

After dealing with the necessity for measuring smoke pollution, and for a comparison between different cities, the author discussed the various methods based on :(a) Measurement of deposit from the air; (b) measurement of suspended matter before it is deposited. The methods of the Advisory Committee on Air Pollution were then described under the headings of: (1) Measurement of deposit by means of standard gauges; (2) measurement of suspended

impurities by means of automatic filters, or records; and (3) measurement with the author's jet dust counter. The last-named instrument has shown the curious variations in smoke impurities in cities from hour to hour. The excessively minute quantities to be dealt with demand the applications of methods more sensitive than those of ordinary analytical processes. For example, the material trapped on dust records from 50 c.c. of air, on an average winter's day in London, weighs about 1/20,000 mgrm., and consists of about 600,000 particles.

2: 4 Dinitrophenylhydrazine as a Reagent for Aldehydes and Ketones, by OSCAR L. BRADY, F.I.C., AND GLADYS. V. ELSMIE.

Aldehydes and ketones can be identified by the crystalline forms, colours, and melting points of the dinitrophenylhydrazones which they yield with 2: 4 dinitrophenylhydrazine. A solution of the hydrochloride is a suitable reagent for aldehydes and ketones soluble in water; it gives a filterable precipitate with 0.003 grm. of acetone or acetaldehyde. The characteristics of the 24 dinitrophenylhydrazones of a number of the commoner aliphatic aldehydes and ketones are described.

The Determination of Phosphoric Acid as Magnesium Ammonium Phosphate, by GUNNER JÖRGENSEN.

The

The most reliable method of obtaining magnesium ammonium phosphate of the correct composition is to precipitate it from a nearly boiling solution (accuracy about 1 1,000). In the author's experience this is the only sufficiently exact method for determining phosphoric acid in mineral phosphates and fertilisers. author's molybdic magnesium method has been the official Danish method for nearly twenty years. Precipitation of ammonium phosphomolybdate in the cold is less accurate (accuracy about 1: 100). cipitation of magnesium ammonium phosphate from a cold solution gives a precipitate so much affected in composition by the conditions of precipitation that the method is unlikely to be made really satisfactory. On the Effect of "Blowing " on the Composition of Certain Fatty Oils, by C. H. THOMSON.

Pre

The effect of "blowing " on a large scale on the composition, the viscosity, and other constants of cottonseed, whale, sperm, and shark oils, has been studied. The rise or fall in the values is simultaneous

SIR OLIVER LODGE ON THE
BEGINNING AND END OF THE
WORLD.

In the course of the Huxley Lecture at the Charing Cross (London) Hospital on December 3, Sir Oliver Lodge based his lecture on Evolution. He said they knew what happened when light encountered a particle of dust, in other words, an atom of matter. It had been investigated in our laboratories and was known as photoelectricity-an electron jumped out of the atom and the atom was ionised. This ionisation of matter by light was becoming, or was likely to become, familiar in medicine. The photographic and chemical actions of light were constantly being studied-its action in polymerising sap in the leaves of trees and vegetation generally, the action of light on the skin also, and its familiar, though remarkable effect on the nervesupplied retina of the eye.

This

How were these chemicophysical actions to be accounted for? Surely by the photo electric property, that was, by the power of waves of the right frequency of vibration to eject an electron from an atom. last process was called ionisation; for the atom, having lost an electric charge of one sign, was now charged with the opposite sign. It was an ion. It was actively and chemically fierce. It was seeking to combine with another. Chemical affinity was in full blast, and the molecular changes is in protoplasm, in silver salts, and in the leaves of trees, occurred. In the retina the nerves were bombarded by the ejected electrons, each striking with an energy appropriate to the frequency of the received vibrations, thus giving the different colour sensations, through the extraordinary interpretative power of the mind through its organ, the brain. The destructive influence of this action on micro-organisms such as an anthrax bacilli, when they were exposed to ultra-violet light, was well known; and the health-giving power of these same ultra violet rays was constantly receiving more and more expert attention.

A study of radiation--radiation of all kinds-had proved of late years intensely illuminating. Thereby that mysterious but fundamental entity, the quantum, had been detected, and thereby the temperature, the constitution, the age, the speed, the history of the various cosmic masses had been and was being elucidated; thereby the formation of woods, and the growth of vegetation on which animal life depended, had been explained; and now the sanitary,invigorating and beneficent work of sunlight on the human organism was being more and more appreciated, and more and more studied and applied by those who had the requisite training, and who would watch for the dangers of excess, and regulate the application of any kind of ray with patience and wisdom. He hoped that a recognition of the electric and ionising power of such rays, which he urged as a reasonable explanation of their chemical and physiological activities, might be a hint in the right direction to those engaged in that work.

Dealing with cosmic evolution, he said it would seem as if the universe as a vital and going concern, must have had a beginning and must have an end. The begin ning was the formation of nebulæ 200 million years ago That end would apparently be the disappearance of matter and the existence once more of an ether filled with perpetual remnants of radiation travelling out in all directions towards infinity with the speed of light at a date incomparably remote. But was that the end? Need there be any end or any beginning? The various stages of cosmic evolution were all concurrent and co-existent, and had it not always been so? doubted whether the idea of termination in any form was tenable, and suggested a theory of the dust of the universe, driven to the confines of space by the pressure of light, receiving the daste radiation, and being ionised by it, chemical activity thus coming toon full blast. Thus would begin once more the clash of atoms, the formation of nebulæ, the birth of stars, and ultimately of planets.

The Glass Research Association Bulletin No. 14 has just appeared. It contains a review of the work of the Association and suggestions are made with regard to future researches on glass and refractory materials. The report was primarily prepared for those connected with the Association, and is apparently not for sale.

ROYAL SOCIETY OF ARTS.
January 21, 1925.

Irish Glass, Old and New, by MRS. GRAYDON-STANNUS.

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The history of Irish glass, like that of so many other arts connected with the Ould Country," is a record of wonderful artistic success combined with financial failure. Unfortunately, the earliest records of the industry are lost and it is impossible to speak definitely of the existence of glass houses in Ireland prior to the 16th century. On the other hand there are many old documents in existence which refer to "Glass Workers" and so make it extremely probable that such factories did exist, but these documents often consist merely of an old account or a receipt relating to work done, and may use the word "Glass-worker " when they mean glazier, and such evidence therefore does not establish the fact beyond dispute. However, at the end of the 16th century there undoubtedly was a factory (or "Glass House ") erected in County Cork, in all probability at a spot even to-day known as "Glasshouse" and which is not far from Curryglass. From that time onwards there are ample evidences of glass houses having been erected in various parts of the country, but in the earliest days of the industry it is extremely difficult to say definitely what particular type of glass any individual factory produced.

a

When we come to the year 1630 (or thereabouts) we find ourselves on surer ground, as about this time glass was being made on a large scale in Dublin, and that city remained famous for its productions from that date right up to 1896. One of its most noted factories, known as the Round Glass House, was in 1729 and onwards, producing really choice specimens, such as dessert dishes (with handles and teet), bowls and goblets, etc., of the nost artistic designs and wonderful workmanship. Very beautiful glass, too, was made in Marlborough Street from 1771 onwards by a firm named Williams, who specialised in chandeliers, candlesticks, bowls, decanters, bottles and even bells. A number of factories were afterwards opened which produced every kind of white and coloured glass associated with Ireland. Many fine specimens still exist and mention must be made of Pugh's productions, which, though rather late from the collector's