There are other meteoric showers than those given in this survey, but they are not so well associated with other comets.

Referring now to Tables III. to VI., and to the B numbers developed by the present writer in connection with planetary and atomic phenomena, a rule is here given which serves to co-ordinate the periods in respect of the comets, or rather the meteoric showers associated with them. This rule must be regarded as fortuitous, and the agreements as accidental, because (1) the grouping of the B numbers is arbitrary, and (2) the periods of the meteoric showers are not all accurately enough established to test any rule of this kind. It, however, serves to fix in mind the unique set of showers which are so well connected with the comets in question. Table III.)

(See also

Referring now to Tables III. to VIII. and "group values" will be understood by working out the satellite B Nos. Not knowing in this particular case what value to take, and assuming that a mean would reduce the possible error, a "grand mean " was taken. Exact agreements are not, of course, significant.

It should be explained here that the B numbers are derivable from planetary and satellite distances as worked out by the present writer, but they are more accurately formulated by the following method (also by the present writer) involving the atomic number of the inert gases thus:

The value 1.4 was found necessary in extending the B numbers to co-ordinate other phenomena by these numbers, while the value 412 became necessary on account of the most distant satellites, barring two which involve a much higher number still (about 795).

Returning to the subject of meteors or meteorites, the latter being a kindred phenomenon, with one or two exceptions no known meteorite has fallen to earth as coming from a meteoric shower. In one case, though it may only be apparent, the Mazapil meteorite (3864 grams) fell on November 27, 1885, near to Mazapil, Mexico, during the shower of Andromedes (Bielids), its composition being largely iron. This event may have been a chance coincidence, but some regard this meteorite as being a fragment of Biela's comet. An 99 iron meteorite fell in England on April 20, 1876, but otherwise no falls were recorded at the dates of the Lyrids.

66

66

Meteors are, therefore, small bodies which are apparently consumed in the upper atmosphere as already mentioned. Those bodies which reach the earth of a size sufficient to be recognised (in transit or recovered), are, are, as is well is well known, termed meteorites.

The masses of these found bodies vary from tiny fragments to 36 tons, or even much larger in one recently reported case in the London Times. Taking the approximate number of meteorites found, and whether "iron" or "stone" specimens, the rough ratio stands, respectively, 261 to

=

B Nos.

373, not taking into account many thousands of fragments. Figures of this kind are, obviously, only rough evaluations.

There is no reason to suppose that the shooting stars are necessarily composed of the same chemical elements as found in meteorites. It may be noted that Blajko observed a meteor, August 12, 1904, which gave, amongst other spectrum lines, one closely agreeing with a thallium line, 3774.1 as compared with T 3775.9.

The composition of meteors,as revealed by the spectrum associated with the nucleus, does not appear to be sufficiently studied to afford much reliable information.

The composition of meteorites has been the subject of much investigation. As an example, a set of analyses is detailed in Roscoe and Schorlemmer's "Treatise on Chemistry," Vol. II. A book on meteorites by O. C. Farrington, was published in 1915, but it is not made use of in this study.

In preparing this article, the writer has made free use of some of the material given in the citations above, and to which may be added a few articles by him in the Chemical News, 1923-24.

(Notes to follow next week.) (To be Continued.)

General Notes.

FIRST INTERNATIONAL CONFERENCE OF THE TECHNICAL PRESS. From October 1st to October 4th a conference organised by the technical, industrial, and commercial Press of France is due to be held at the Hotel du Cercle de la Libraire, Paris, Boulevard Saint Germain. The Committee is a representative one and the congress promises to be both interesting and useful.

EXPECT TWENTY COLLEGES AT

CHEMICAL EXPOSITION.

About twenty leading American colleges and universities have filed applications for their students of chemistry and chemical engineering to take the one-week course of intensive training in practical technique of chemical engineering to be held in conjunction with the Tenth Exposition of Chemical Industries at the Grand Central Palace, New York, during the week of September 28 to October 3. More than three hundred students are expected to enrol before the

closing date. All students of recognised colleges, as well as practicing chemical engineers, who desire to brush up on fundamentals, are eligible to take the course, which is without cost.

MANUFACTURE OF STEEL AND IRON IN SWEDEN.'

The Journal of the Chemical, Metallurgical, and Mining Society of South Africa for May contains an interesting account of the above subject by L. Nordenfelt.

Iron was made in Sweden and fairly generally used about 500 years B.C. The only ore used was for a very long time alluvial hæmatite collected in the form of mud from mires and the bottoms of lakes. The product was not pig but soft iron called osmund iron. Real mining of iron ore is known about the year 1300, and has probably taken place earlier. About 1450 pig iron was manufactured, and from this time we can consider that a real industry has existed.

SPIRITS AND BRANDIES.

An interesting paper on the comparative results of the analyses of spirits and brandies which was read before the Cape Chemical Society on 22 August, 1924, by F. Fevrier, B.A., Assistant Viticulturist, has been reprinted by the (Government) Division of Chemistry, Pretoria (Chemistry Series No. 55.)

THE BRITISH CHEMICAL PLANT MANUFACTURERS' ASSOCIATION.

The British Chemical Plant Manufacturers' Association held its fifth annual general meeting at 166, Piccadilly, W.1., on Wednesday, July 22, 1925, when the report of the Committee was unanimously adopted.

The Committee has commenced active propaganda with a view to bringing before chemical manufacturers the desirability of utilising British plant. With the concurrence of the Organising Committee of the London Meeting of the Society of Chemical Industry in July, 1926, an exhibition of chemical plant is being arranged, and a subcommittee consisting of Dr. R. Seligman, Mr.. A. Reavell, Mr. E. A. Alliott and Mr. W. J. U. Woolcock has been appointed to prepare the plans.

The following officers were elected for 1925-26:

Chairman-Dr. R. Seligman. Vice-Chairman-Mr. J. A. Reavell. Honorary Treasurer Mr. E. A. Alliott. During the evening a successful dinner was held at the Holborn Restaurant. The guests of the Association were Mr. F. H. Carr, Mr. J. V. N. Dorr, Mr. E. V. Evans, and Mr. R. L. Mond. The speeches were characterised by a call for greater sympathy between British plant manufacturers and their clients, the chemical manufacturers. A number of the speakers referred to methods adopted by continental competitors and emphasis was laid on the necessity for the plant manufacturers to understand the processes which were to be carried out. Mr. Dorr, in particular, referred to the successful results which had attended the holding of chemical exposition in New York, and wished prosperity to the Association's plans for next summer.

NEW ZINC REFINERY TO OPERATE IN CANADA.

The large new zinc refinery of the Consolidated Mining and Smelting Company, Limited, which has been under construction for some months, is expected to commence operations early in August. This will mean that the export of refined zinc from the Company's plant in the interior of the province will be materially increased, and, unless the demand for zinc grows rapidly, shopments of concentrates will be replaced in time by refined metal. Expirts of lead and zinc last year were about two-thirds greater than in 1923. The Orient and the Unitel Kingdom are expected to take the entire output of the new refinery.

PROCEEDINGS AND NOTICES OF SOCIETIES.

PHYSICAL SOCIETY OF LONDON. Proceedings at the Meeting held on June 12, 1925, at the Imperial College of Science. F. E. Smith, C.B.E., F.R.S., President, in the chair.

A paper On Mass and Energy was read by G. Temple, Ph.D., Imperial College of Science.

ABSTRACT.

It is assumed that variations in the potential energy of a body (gravitational or electrostatic) are always accompanied by proportionate changes in its mass. Con

tinuing this assumption with the theories of Newtonian dynamics and Maxwellian electrodynamics, it has been found possible to predict all those phenomena, which are usually regarded as the crucial tests of the theories of relativity, both "special" and "general."

DISCUSSION.

Prof. A. S. Eddington (communicated) : I have had the opportunity of reading Dr. Tempie's paper. ▲ nave no quarrel with his mathematics, and have often admired the elegance and ingenuity of his methods. But it seems to me that work of this kind can only appeal to someone who has already been led to believe that the relativity theory is fallacious. Otherwise i cannot imagine why anyone should reject the complete physical theory of Einstein, and prefer the method proposed by Dr. Temple (and others) of an arbitrary tinkering of the fundamental equations. It seems to me that Einstein's method, which consists in rejecting certain hypotheses which had crept into current physics without any experimental support, and re-examining our Knowledge unbiased by these traditional hypotheses, goes deeper and is more convincing than any proposal to patch up the Newtonian equations by addition of extra

terms.

I do not think that the success in explaining" crucial" phenomena is greater than would be expected from the additional constants introduced. It would be interesting if a term added to explain change of mass with velocity were found also to explain the gravitational deflection of light. But it does not. It gives only half the observed deflection; and the discrepancy has to be cured by arbitrarily doubling the terms. The displacement of the Fraunhöfer lines is not explained; Dr. Temple tackles it by a procedure justified if the relativity theory is accepted, but admittedly unjustified on his own theory, and obtains a result which the experimental evidence (such as it is) does not seem to favour. The fine structure of the hydrogen lines is scarcely an additional success; the discussion of this phenomenon was required in order to remove an apparent difficulty in Dr. Temple's theory which does not arise in Lorentz's or Einstein's theory. I think the one distinct success is in deriving the perihelion of mercury and the deflection of light from the same formulation of the equations; but even here it seems that we

are required to accept a conclusion of the relativity theory (whilst rejecting the arguments that led to it. Surely the discovery that gravitation acts on light-waves compels us to reject the Newtonian picture of gravitation as a force-you cannot deflect waves by tugging at them; Newton's picture of the invisible agent that pulls down the apple does not correspond to an agency which can deviate a train of waves. We have to find (as Einstein has done) a new picture of the gravitational field which shall represent its action on waves as well as on particles; and it is this new picture which gives us the hint as to the natural formulation of the law of gravitation.

Dr. D. Owen said that the author had set out to provide a theory more congenial to experimental physicists than Einstein's, but though the hands were the hands of Esau the voice was Jacob's voice. The theory put forward appeared to him identical in principle with Einstein's theory, though expressed in another form. He would like to ask the author whether his theory left any room for the ether? Apparently it did not, and although some physicists had dispensed with the ether without discomfort, others felt that its loss had left a blank. Then the fundamental equation (2.1) of the paper is simply a form of that Einstein result which identifies enerby with mass, a result that is bound up with the implications of Einstein's theory. In equation (2.7) the author introduces a " proper time " T, but if the physicist cannot have his absolute time he is not much better off with one sort of proper time than he is with another. In dealing with the shift of the Fraunhöfer lines the author speaks rather contemptuously of the "naïve procedure " of assuming a certain behaviour of "atomic clocks," but apparently he makes a very similar assumption himself. It is true that he arrives at a shift of different numerical value from that deduced by Einstein, but there is no great difference in principle. The theory contains another weak spot in the fact that the factor has different values for gravitational and electrical fields. The mathematical skill displayed in the paper,however, was of an order to excite the admiration of the most hardened of experimental physicists.

Capt C. W. Hume (communicated subsequently): The metaphysical significance of the paper seems to lie in the fact that it further delivers us from those strange

paradoxes concerning the nature of space and time with which Einstein has troubled

it is

our peace. To anyone who holds the idealist view of the universe a dispute as to the reality of the ether is a dispute about words, for ether and matter are in any case mere intellectual fictions which (like the virtual image in optics) serve to co-ordinate the elements of our experience. But when we are asked by Minkowski's famous dictum to believe that space and time are in some way identical in their nature, that is a very different matter. It has happened before now, as in the case of Carnot's theorem, that the mathematical structure of a theory has had to be separated from the metaphysical content in association with which it was first put forward possible for the former to be true while the latter is false. The author has shown that the mathematical structure of Einstein's theory can be retained in essentials while an entirely different metaphysic, his or another, is associated with it. May I also evnture to suggest that Minkowski's dictum about the identity of time and space is based on a fallacy which arises from taking in a literal sense the loose statement that the time-space systems of two relatively moving observers will be different from one another. As a matter of fact, the nature of the universe is precisely the same for all observers, even on the principle of relativity; the orientation of the time-space axes is different for different systems of measurement, but any observer can choose any system of measurement he pleases. In the loose phraseology commonly employed, each observer is presumed to use that particular system of measurement which in practice it would be most convenient for him to use; but there is no reason in principle why he should not measure time by a flying clock and measure space with highspeed measuring rods, if he chooses. In connection with the metaphysics of relatiity it is worth noting that the time order of events in the experience of any one monad is the same 66 for all observers" or, rather, whatever space-time- co-ordinates you adopt, the experiences of any monad will occur in the same order, and this order is the only thing in common between clock measurements and our consciousness of time. And, secondly, any statement which contradicts our immediate intuitive judg ments must be fallacious, because the statement itself must at best rest ultimately on intuitive judgments which themselves have

no greater authority than these. Now if there is any intuitive judgment that is clear and certain, it is this, that time and space are two entirely different conceptions, having nothing in common except a remote analogy between order in space and order in time. Hence, if any theory contradicts this fact, either that theory is untrue, or it 10olves an antinomy in the very nature of thought.

AUTHOR'S REPLY.-The very kind criticism of this paper which I have received from Professor Eddington encourages me to point out an aspect of the subject which appears to have escaped notice. I would be the last to deny the cogency of the observations which Professor Eddington has made, but I have the uneasy feeling that they tell equally against relativistic theories. Thus, though Einstein's work is spoken of as a "complete physical theory," based on the rejection of certain unverified hypotheses, a perusal of such a work as Professor Whitehead's "Principle of Rela tivity," with its four sets of gravitational equations, shows that there is an arbitrary element in the selection of the Einstenian gravitational equation Gmr=0; while the methods adopted by all relativists in reformulating the equations of the electromagnetic field are frankly selected in order to obtain Maxwell's equations as a iirst approximation. Such a procedure may not unjustly be described as "tinkering with the fundamental equations." Again, arbitrary constants and even, horresco referens, arbitrary functions are not entirely unknown in the General Theory of Relativity. Thus Cambridge (Phil. Mag. Vol. 45, pp. 726-732) has shown that the direct integration of the Einsteinian equations for a field possessing spherica Isymmetry leads to the result (for the line-element of the dynamical manifold)

two boundary conditions), usually conveniently identified with r itself. There is necessarily an element of contingence in the fundamental equations of any dynamical theory, and all that the present theory can claim is a certain simplicity and intelligibility in its formulation, and a certain agreement with experience in its conclusions. In reply to Dr. Owen, I wish to emphasise the fact that although there is a certain similarity in form between the methods of the present paper and Einstein's theories, there is a radical diversity of principle. Thus, although equation (2.7) introduces a new variable "r," named, perhaps somewhat unfortunately," the proper time," I have deliberately refrained from attaching to this variable any physical significance, such as Minkowski would have attached to the variable bearing the same name in his interpretation of the Special Theory of Relativity; and I have explicitly stated that the one purpose served by the introduction of this variable is the expression of the equations of motion in Newtonian form a matter of mathematical convenience rather than of metaphysical necessity. Again, the "identification of mass and energy in Einstein's theory, alluded

=

to by the same speaker, is a loose, if useful, contraction of a deduction from the Special Theory of Relativity, more accurately expressed in the statement that a flux of kinetic energy w with velocity v is accompanied by a momentum g w.v/c2 (see Chapter XIII., "The Principle of Relativity," E. Cunningham, Camb. Univ. Press, 1914). The deduction assumes that the group of transformations admitted by the equations of particle dynamics is isomorphic with the Lorentz transformation. The assumption of the present paper is distinct from this result of Einstein's, both in origin and in expression, for it does not presuppose or imply the Lorentz transformation, neither does it contain any reference to kinetic energy. Finally, it appears that

both Dr. Owen and Dr. Thomas confuse the special and general theories of relativity. The assumption of that particular consequence of the special theory of relativity, to which allusion has just been made, cannot be used to predict the phenomenon of $3, neither by itself, nor when supported by the supplementary hypotheses of Poincaré (pp. 173-180, (loc. cit.), or of Silberstein (Phil. Mag. Vol. 36, pp. 91-128). The advance of the perihelion of mercury has been explained on relativistic principles, only by