APRIL 10, 1891.]

as declared a dividend of 6 per cent. for the past year on its preferred hares, carrying forward £1,508 5s. 5d.

All the foregoing dividends on the shares held by this company ave been brought as usual into the accounts appended. The branches worked directly by the company nearly all exhibit an improvement n previous returns, which is partly due to the rise in silver.

In order to provide the Telephone Company of Egypt with further working capital for extensions in that country, your directors have aken up £1,500 of its 6 per cent. debentures. The accounts of the bina and Japan Telephone Company have not yet been closed, but hey point to a small surplus after paying debenture interest.

By a recent Act of Parliament, companies are enabled, at a modeate expense, to amend their memoranda of association. The direcors, whilst they will always bear primarily in mind the original bjects of this company, have come to the conclusion that it is deirable that the powers of its memorandum of association should be xtended so as to authorise the supply of electric apparatus and material, and the application of electric power generally.

The resolution mentioned in the notice on the back of this report will therefore be submitted for the consideration of the meeting.

The retiring directors at the present meeting are the Right Hon. .A. F. Cavendish Bentinck, M.P., and Mr. B. St. John Ackers, both f whom being eligible, offer themselves for re-election. The auditors f the company, Messrs. Deloitte, Dever, Griffiths & Co., also reti e, nd offer themselves for re-election.

CR.

By Telephone patents, goodwill, &c., £71,000; expenditure on exchanges to date, £34,832 19s. 7d.; less written off to profit and loss, 1890, £832 19s. 7d.

...

Shares, &c., held in subsidiary companies11,825 Preferred shares in Telephone Company of Egypt, Limited, of £5 each; 3,875 deferred shares in Telephone Company of Egypt, Limited, of £5 each; 14,136 shares in China and Japan Telephone Company, Limited, of £1 each;

14,810 shares in Bombay Telephone Company, Limited, of Rs. 25 each;

5,516 shares in Bengal Telephone Company, Limited, of Rs. 100 each;

50 7 per cent. mortgage debentures of China and Japan Telephone Company, Limited, of £100 each;

15 6 per cent. mortgage debentures of Telephone Company of Egypt, Limited, of £100 each;

Indian Government paper, Rs. £1,000

Stores on hand

At branches, £1,993 15s. 8d; less reserved for depreciation, £500

1,493 15 8

£ s. d.

2,162 8 3

225 2 1 8,835 8 11

£11,222 19 3

£ s. d.

10,864 12 6 347 1 9 11 5 0

£11,222 19 3

Cash at Alliance Bank, fixed deposit, £3,000; on current account, £753 10s. 11d.; and in hand and with agents abroad, £826 11s. 6d.

£215,302 4 9

The

New Australian Electric Company.-This company held its annual meeting in Melbourne on the 23rd of last month. report submitted to the meeting stated that during the past 12 months 1,000 extra lamps had been supplied, 1,400 extra lamps had been installed and were awaiting electric current from the stations, and 900 lamps had been supplied for isolated plants. The Richmond station was being enlarged by the addition of four more engines, dynamos and boilers, which would bring its capacity up to 28,000 lamps. The chairman stated that during the past twelve months their nett profit had amounted to £3,615 16s. 5d., and that the total balance of £4,716 4s. 8d. meant a 20 per cent. profit on their paid up capital. No dividend would, however, be declared, the principal reason being that the company intended to make very large extensions in its stations and mains.

The Eastern Extension Australasia and China Telegraph Company, Limited.-It is stated that the accounts to December 31st show a profit balance of £106,257 after payment of three interim dividends. The directors propose to distribute, on April 22nd, the usual dividend of 2s. 6d. per share, making a total dividend of 5 per cent. for the year 1890, besides a bonus of 4s. per share, or 2 per cent., making a total distribution of 7 per cent. for the past year, £25,007 having been carried to the reserve fund, which now stands at £495,239.

Erie Telegraph Company.-The directors have under consideration a proposition from a party representing a Texas syndi cate to sell a portion or all of their 70 per cent. interest in the stock of the South Western Telegraph and Telephone Company for $700,000, which is equivalent to $50 per share for the Erie stock.

St. James and Pall Mall Electric Light Company. -The allotment letters for the 10,000 £5 preference shares recently offered by the St. James and Pall Mall Electric Light Company, Limited, have been posted.

The Brazilian Submarine Telegraph Company, Limited. The receipts for the week ending April 2nd, 1891, amounted to £5,136.

The City and South London Railway Company. The traffic receipts for the past week amounted to £901.

The Cuba Submarine Telegraph Company, Limited. The estimated traffic receipts of the Cuba Submarine Telegraph Company, Limited, for the month of March, were £4,000, as compared with £4,018 in the corresponding month of last year.

Direct Spanish Telegraph Company, Limited. The estimated traffic receipts for the month of March, 1891, are £1,930, as against £2,382 in the corresponding period of last year.

The Eastern Telegraph Company, Limited. The traffic receipts for the month of March were £58,447, as against £58,471 for the same period of 1890, or a decrease of £24.

The Great Northern Telegraph Company. Receipts in March, 1891, £22,800; 1st January to 31st March, 1891, £64,400; corresponding months 1890, £60,200; corresponding months 1889, £63,000.

The Western and Brazilian Telegraph Company, Limited. The receipts for the week ending April 3rd, 1891, after deducting 17 per cent. of the gross receipts payable to the London Platino-Brazilian Company, were £4,165. The West India and Panama Telegraph Company. The receipts for the ha month ended March 31st, 1891, are £3,338, as compared with £3,850 in corresponding period of 1890.

APRIL 10, 1891.]

THE PROPAGATION OF THE

HERTZ

ELECTRIC UNDULATION IN AIR.

By MM. EDOUARD SARASIN AND LUCIEN DE LA RIVE.

WE had the honour of presenting to the Academy the first results which we obtained on repeating M. Hertz's splendid experiments on rapid electric oscillations.* We confined ourselves then to the case in which the electric undulation is transmitted along a conducting wire; since then we have repeated another of M. Hertz's experiments, which consisted in following the propagation of the electric induction through the air in the absence of any metallic conductor. The primary exciter is placed in front of a large plane metal screen and parallel to it. The electric undulations proceeding from it are propagated through the air and reach the metal screen, which serves as a mirror for them, the reflected waves then forming with the direct waves, a system of stationary waves, the first node of which is at the mirror.

In order to study the system of sound waves established in front of the mirror, the circular resonator is placed in two different positions; (1) it is kept constantly parallel to the mirror and to the primary, i.e., in the plane of the wave; (2) it is displaced in the plane followed normally on the mirror by the axis of the primary, the plane of vibration. In both cases the results agree absolutely as regards the position of the equi-distant maxima and minima of electromotive force. Besides these two methods, M. Hertz has employed a third, which consists in causing them to be crossed on the same resonator by the waves reaching it from a single exciter, either directly through the air, or along a conducting wire.

475

We sum up in the following table the results which we obtained with 10 different circles.*

In this table, we give the mean of the measurements obtained with each circle, and for the sake of brevity we have not separated those obtained with primary exciters of different dimensions, these measurements not showing any systematic difference. In these last experiments in the air, as in our former trials along the wires, we found, in fact, that a circular resonator always gives the same length of wave, even when the dimensions of the primary vary within certain limits. Thus, then, here again we observe what we have termed multiple resonance.

In the case of great lengths of wave circles of 1 metre and 75 of a metre, which are very soon carried far beyond the mirror, being almost comparable to the direct action of the primary, only one ventral segment and one node is to be observed with any degree of precision besides the node which occurs on the mirror itself. With smaller circles, to which the dimensions of the mirror are better suited, we can easily distinguish three ventral segments and three nodes, including that of the mirror. The equidistance of the ventral segments and nodes is, we find, fairly satisfactory.‡

The most important of our work is shown by the comparison of the figures in the last three lines of our table, which show that the wave-length obtained for each circle in the case of propagation through air, is to all intents equal to that which the same circle gives along the wires, the quarter of both being very nearly equal to double the diameter of the corresponding circle. Whence it follows that the speed of the propagation of the Hertz electric undulations through air is to all intents the same as that with which they are transmitted along a conducting wire.§

From these experiments he concludes, from the great wave lengths of the mirror, that the rate of propagation through the air, in the absence of any conducting wire, is nearly double that observed along a wire, and that these two speeds are in the ratio of 7: 4, which does not bear out Maxwell's theory, he having maintained that these two speeds were equal.

Having regard to its importance from a theoretical point of view, we gave special attention to the verification of this point. Having proved, by our former experiments along the wires, the constancy of the undulating period of a given circular resonator, whatever may be the primary exciter by the action of which it is brought into play, the same exciter, on the contrary, showing as many wave lengths as we employ circles of different magnitudes, we applied ourselves to the comparison of the length of wave given by a circular resonator along wires with that which it gives in the air in the absence of wires.

As a reflecting surface, we employed a large sheet of lead, 28 metres high, and 3 metres wide, kept plane and vertical by its own weight. The primary exciters and the large Rhumkorff induction coil were the same as we used in our preceding experiments. The exciter was placed in front of the mirror, its axis being horizontal, and its interruption at the normal point in the centre of the metallic screen. Its distance from the latter varied from 4 metres to 10 metres. The circular resonator was fixed on a carriage sliding along a large wooden bench already described.

We have varied the conditions of the experiment considerably, and repeated the observations several times.

Comptes Rendus, January 13th, 1890.

MAGNETIC MINERALS IN METEORIC IRON.

THE meteoric iron obtained from various districts in Hungary, but especially from Magura and Arva, has recently been placed under examination by Weinschenk, Berthelot, Friedel,

and others.

Amongst the constituents several highly magnetic minerals have been discovered. The principal mass of these meteorites, which are found in Hungary, consists of heavy irregularly

* The sensibility of the micro-metric screw is a very important item in researches of this kind, especially with small circles which only give very feeble sparks. In the last case we used a screw giving the 400th part of a millimetre.

The intensity of the spark of the resonator being much more feeble in this experiment than in that with the wires, and, moreover, diminishing much more rapidly in proportion, the observations are, on the whole, less clear than with the wires. In order, therefore, to work under favourable conditions, we must see that the dimensions of the primary are suited to the diameter of the resonator. The limits between which we can conveniently observe the multiple resonance are less extensive than in the case of the wires, but vary easily from single to double, and even more.

M. Hertz places the first node at a certain distance behind the mirror; this discrepancy at the extremity does not seem to occur in our experiments. As we see by the table, the first quarter of a wave length does not show any appreciable systematic difference from the others. § We have already published this theorem in a preliminary communication on the subject to the Société de Physique et d'Historie Naturelle, Geneva, on May 1st, 1890 (Archives des Sciences physiques et naturelles, vol. xxiii., p. 557); but since then we have taken up these researches anew, varying in many ways the conditions of the experiments, and it is these last experiments that we have summed up in this paper. M. Lecker, of Vienna, has found by quite a new method that the speed of the electric undulation along a wire is equal to that of light.

shaped fragments, which appear to consist of an alloy of iron, nickel, and cobalt, probably of the formula Fe, (Ni Co): these fragments are very strongly magnetic.

Reichenbach's ". "tænite was also found: this is another compound of iron, nickel, and cobalt, associated together in proportions represented by the formula Fe, (Ni Co)2. It occurs in thin, silver-white, strongly magnetic lamellæ.

The most interesting mineral found in these meteoric masses is a new one, for which Weinschenk has proposed the name "cohenite." It is a curious compound of iron, nickel, and cobalt with carbon. It occurs in white regular

crystals, resembling tin in colour, and which are very strongly magnetic. Chemical analysis revealed the composition to be C (Fe Ni Co)3.

The

Weinschenk claims to have discovered diamonds in this meteoric iron. He compares the varieties of carbon met with in these meteorites with those in pig-iron. "hardening carbon," about which we have heard so much lately from Professor Roberts-Austen and others, corresponds with the carbon given off as hydrocarbon when meteoric iron is dissolved in hydrochloric acid; the ordinary "carbide iron" with "cohenite;" graphitic "tempering carbon" with the carbon in the residue when meteoric iron is dissolved; and, lastly, graphite is met with in both varieties of iron.

This perfect analogy leads to the assumption that the conditions under which meteoric iron was formed are comparable to those under which pig-iron is produced, and the presence of the diamond indicates that the carbon dissolved or chemically combined in iron can, under certain conditions, separate out in the allotropic form of the diamond.

AN ELECTRICAL METHOD OF DETERMINING THERMAL EXPANSION FOR EQUAL QUANTITIES OF HEAT.

THE expansion caused by the communication of one calorie of heat may, according to E. J. Dragoumis, be determined in a new way as follows:

A dilatometer packed with cotton wool is used. This contains the substance, the thermal expansion of which is to be determined. The instrument also contains a spiral of platinum wire, the ends being fused through the walls.

The substance is heated by means of the platinum spiral through which a current of about 0.2 ampère is passed.

Since the current can be easily and accurately measured it is possible to determine the amount of heat that is communicated through the spiral to the substance under examination, and the thermal expansion due to this can be observed. The calculation of the results of the observation is performed by the following scheme.

[APRIL 10, 1891.

THE HUNGARIAN MINISTER OF COMMERCE AND THE BUDAPEST ELECTRICAL TRAM. LINE.

[FROM OUR OWN CORRESPONDENT.]

I HAVE recently called your attention to an "interpellation * brought forward in the Budapest Council of Municipal Re presentatives by occasion of the fact that members of the Metropolitan Tramway Commission have taken part in the conclusion of the definitive agreement between the capital and the Electrical Tramway Company of Siemens and Halske, and have immediately afterwards been elected directors of the joint-stock company, which was floated by the Anglo bank simultaneously with the Austrian General Electric Com pany, and concerning which it was said by the whole Press that it had acquired the Budapest tramline from the firm of Siemens and Halske.

In consequence of this, the persons referred to in the interpellation leave the board of the Metropolitan Railway. At the same time there appeared an explanation by the line in question, which conveyed to the public the startling intel ligence that the Budapest electric line was the exclusive property of Siemens and Halske's town line undertaking, and that at present no agreement existed between this undertaking and the electric railway company.

This explanation has been variously interpreted, and further light is thrown upon it by a peculiar edict of the Royal Hungarian Minister of Commerce. This edict runs as follows

To the Budapest Town Line Undertaking-Siemens and Halske.

The shares issued in Budapest by the Municipal Electrical Line Company enjoy, as it is said, a great demand, and are bought and dealt with at a considerable premium, and, as I have been informed, on the supposition that the abovementioned company has bought up electric lines for which the Siemens and Halske Company have received a concession, or that the company has been constituted for the purpose of working these lines.

According to the stipulations of the concession granted to the undertaking of Siemens and Halske for constructing and working the electric lines, this concession can be assigned to another undertaker only after my consent has been previously obtained.

As I cannot allow a possible deception of the public, I inform the Budapest Town Lines Undertaking-Siemens and Halske-that it must explain to the public through the press in such a manner as to exclude every doubt concerning the kind of relation existing between the said company and the representation of the city, and that it must report to m within three days, and in the unexpected case that the company should, in spite of its obligations, was founded by the Siemens and Halske undertaking as concessionary for the electric tramways, it must apply for my sanction with an immediate exposition of its prospectus and rules, and pending my sanction the activity of the company, and especially the issue of shares, must be suspended.

The New Pester Journal, a respected paper of extensive circulation, approves of the attitude taken by the Minister Baross, and hopes that he will succeed in shutting the door against the tricks of the share market.

This letter does not deal with electro-technics at all, but discusses financial stratagems.

ELMORE'S COPPER TUBES.

MR. ALEXANDER WATT sends the following letter to the Financial Times, under date of April 4th :-" As to the system of floating company after company to purchase patents for a process which in no degree has been proved to be a com mercial or even a practical-success, I will leave sud matters to the consideration of the financial Press, trusting that it will look well after the public interest with increasi watchfulness. There are, however, some practical pos respecting the character of the copper deposits obtained the so-called Elmore process' to which I should like t

APRIL 10, 1891.]

irect attention, in order that the public may judge for Themselves as to whether the merits of this process are equal o the plausible representations that have been put forth conerning it.

6

"I have before me a copy of the Engineering and Mining Journal, of New York, dated 21st March, which contains a eading article on the Elmore process, one or two passages rom which I will quote. The writer says, Unfortunately, t is only in actual practice that the defects of what in theory seems to be a satisfactory process can be ascertained; and, In the case of Elmore's invention, the difficulties appear to come in the foliated character of the deposit, which, notwithstanding the pressure of the burnishers, upon heating even to a very moderate degree, exfoliates.

6

If we are

correctly informed from what we consider reliable sources, the company owning the Elmore process is not content to await the perfecting of the process before reaping a harvest; indeed, it is very openly charged that the process is being worked as a stock speculation rather than an industrial investment.' Now, with respect to the exfoliation' of the copper deposited under the influence of a burnisher, as in the Elmore process, I will direct attention to one or two practical facts which may tend to dispel some of the illusions which the public have been led to entertain as to the extraordinary merits of the Elmore process.' In the first place, it may be accepted as a fact that electro-deposited metals do not adhere to polished or burnished metallic surfaces. If, therefore, a burnisher passes over the surface of a revolving iron mandril coated with copper, it leaves a bright and highly polished (or burnished) surface to receive the next deposit, with which it has no cohesion, and thus becomes a distinct and separate layer or film; and this deposition of non-adherent, and indeed laminated, metal, layer upon layer, goes on throughout the entire body of the metal deposited, rendering it totally unfit to withstand even a very moderate heating without coming to grief in some way-disintegrating, in fact. Again, the action of the burnishers, under a pressure, as we are informed of from 3 to 13 lbs. would cause the non-adhering films of metal to expand, and thereby assist the separation of the respective layers in contact with, but not adhering to, each other. A soft metal, such as copper, would expand very considerably under a burnishing pressure of even 10lbs., or much less when applied to a very thin film of the metal-such as would be deposited before the Elmore burnisher made its return journey over the revolving copper tube. If, therefore, the exfoliation of the metal be due to the cause I have pointed out, it is not a remediable defect, since the action of the burnisher is solely responsible for the foliated condition of the metal. There is another fact in connection with the electro-deposition of metals, which is very likely to be overlooked, but which must be considered when comparing the professed superiority of the electrodeposited tubes with ordinary drawn tubes. It is this: Metals deposited electrolytically do not adhere well, if at all, to their kind. Thus, gold will not adhere to gold, nickel to nickel, nor copper to copper. If, therefore, there be any breaks in the continuity of the deposition-even for an instant, and quite irrespective of the receiving surface being excluded from the air by the surrounding liquid, or electrolyte-as soon as the operation again proceeds the subsequent deposit will, I believe, be a distinct and separate layer or film, and as often as such breaks occur so will there be deposited a succession of separate layers of the metal-one tube over another, as it were. But even this probable cause of mischief is as naught compared with the more serious evil of foliation, for which there would appear to be no remedy but the abandonment of the burnisher."

66

477

5,192. Improvements in electric clocks." W. S. SCALES. Dated March 24th. (Complete.)

5,247. Improvements in electric heating apparatus." (M. W. DEWEY. Dated March 24th. (Complete.)

5,252. "Electric signal apparatus for railway trains.” GRAFF. Dated March 24th. Complete.)

E. D.

5,280. Improvements in electric switches." W. P. THOMPSON. (Communicated by Willing and Violet, Germany.) Dated March 24th. (Complete.)

5,313. "An improvement for driving electrical machinery." H. AYLESBURY. Dated March 25th.

'Improvements in or relating to arc lamps." F. R. BOARDMAN and J. S. FAIRFAX. Dated March 25th.

232.

Improvements in electro-motors and dynamo-electric machines." J. HOPKINSON, E. HOPKINSON, and G. A. GRINDLE. Dated January 6th. 8d. Claims:-1. In electric locomotives or in vehicles propelled by electric motors the combination of two or more armatures having independent parallel shafts, each driving an axle or axles, with field magnets arranged so as to form a single magnetic circuit, which includes the armatures, the lines of magnetic force passing through the armatures in succession. 2. The construction of contact pieces or brushes for commutators from a carbon rod held in a split tube or holder of brass or other metal or material through which contact is made. 3. Carbon contact-pieces constructed as described in combination with metal plates to which they are attached, and which are placed tangentially to the commutator and held by a holder and spindle, the contact against the commutator being obtained by spring in the plates or by a spring in the holder, or by connecting the opposite plates by a spring. 4. The combination of the carbon contact piece and split tube or holder with a smaller plate to which the tube is attached, with a pocket or recess on the tangential plate, as and for the purpose described. 5. The combination of the single magnetic circuit and two or more armatures, substantially as and for the purposes described.

66

873. Improvements in electric supply meters." J. PERRY. Dated January 17th. 8d. This principle is that an electric motor either with permanent field magnets or shunt electro-magnets, resisted in its motion mainly by Foucault currents, gives a good supply meter. 8 claims.

911. "Method of and apparatus for winding ribbons or tapes of insulating material around electrical conductors." SYDNEY PITT. (A communication from abroad by J. B. Atherton, of New York.) Dated January 17th. 8d. According to the present invention, the wire passes centrally through the paper bobbin or roll, which, being revolved as the paper is taken from it, the paper is laid spirally around the wire. 7 claims.

993. 'Improvements in holders for incandescence electric lamps." J. W. EDMUNDSON and W. CLARKE. Dated January 20th. 8d. Comprises two porcelain blocks, with or without a cap or cover. Between these blocks there are secured a number (say four) of springs or prongs, shaped to embrace the lamp neck when it is applied to the holder, and the grasp of these springs or prongs is further aided by an elastic ring, such as a ring of spirally wound wire, which is placed