ELECTRICAL INVESTMENTS.

ECTRICITY is rapidly becoming a speculative edium. A glance at the list of provisional orders s the mind thinking of the vast amount of capital ich will have to be embarked if a quarter of them ly are to be carried out, and, whether the hopes of I the promotors will be realised. For, on the system opted must depend the profits to be gained; and the transformer or the secondary battery be the ore economical has yet to be decided. Electricity as weathered many troubles, and this question will ecide itself, perhaps in the coming year.

Illuminating gas, in its early days, had its trials like 1 young things, and it was a long time before it cut its eth and got over its infantile disorders. It started by ghting the streets. It would never be available for ghting houses, that was certain. No sane man would ave it. It would blow up any lunatic who tried it, nquestionably. But the British Isles being populated y "mostly fools," according to Carlyle's dictum, its habitants were cajoled by the gasmen into its use; nd, presumably, the blow-up portion was so small hat, where the angels feared to tread, others rushed in, nd, lo! nearly every house in Christendom is lighted y its agency. "He's got a lot of gas shares" is quite afficient to account for a full waistcoat and comortable circumstances.

It is a well-known fact that it is not to street lightng that the wealthy gas corporations look for their evenue, but to the meter returns of the houses. The as companies are vested with great powers, and have become a huge monopoly. Ostensibly, this is not the ge of monopolies. They are corrupt, and the age is virtuous. When it became evident that it was possible o light streets and houses by electrical means, the powers that be, guided by the light which gas had thrown upon them, bethought them that they would show their wisdom by guarding the weak ones, who might be tempted, like moths, to fly to the new light, from getting burnt in the transaction.

Institution of Electrical Engineers (continued) Physical Society

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Abstracts of Published Specifications

Correspondence:-Teachers and Students

Energy and Electricity

No. 630.

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A Bill was framed which most effectually encompassed its object; it did more, it effectually prevented the general adoption of electricity, and nearly stifled for a time the electric lighting industry. Rumour had it that gas shares were at the bottom of that Act. But rumour is a notorious liar. They were doubtless "all honourable men," but misguided. Electric lighting was a robust child, even in its infancy. It was not to be denied. It did a little crying, and then went to school and learnt its letters diligently. Very many of the companies and firms started for its exploitation, finding their sphere narrowed, and their profits nil, succumbed, and their personnel were scattered, like the dragon's teeth, only to raise up a noble army of electrical engineers, all of them ready and willing to put the light into your house at the shortest possible notice for a consideration. But it is the consideration which is the rub. "Can you give it me at the same price as gas?" is the almost invariable question put by the enquirer after truth concerning electric light. He does not care to take a leap in the dark, which would land him in light, without economy to sweeten it. But the name of those who have indulged in its refulgence, regardless of the initial outlay, is legion. Men having valuable pictures and costly decorations have doubtless seen a real saving in its adoption, and have accepted it. Many of the wealthy have needed no other reason than that, seeing its superiority, they have meant to have it, and given the order. It is a luxury, and as such, has to be paid for. There are no statistics to show the number of isolated plants at work; but they are much more numerous than those who are not alive to the question have any conception of, and the amount of capital already laid out by private persons must total up to a very considerable sum.

It is probable that the first electric lighting Act did good in a way which was not intended. The stagnation which it caused gave time for the perfecting of details, and saved the squandering of much money on undigested schemes. The time, however, of pupilage

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is passed, and given more security by the amending Act, the electric lighting industry, without nursing or undue favours, is quite capable of taking care of itself. It is not to be expected that the light can be within the means of the struggling classes, but there are many localities denizened by those who are willing and able to pay a reasonable price for the great advantages which it has to offer over its rival, gas. Now, that instead of every house having its separate plant, districts are being operated from central stations, not only will the charge be placed upon an acceptable basis, but such enterprises ought undoubtedly to be profitable. That is now a mere question of figures. There is no longer any question as to the possibility or failure. If only the capital be forthcoming, and a good proportion of the inhabitants of any well-to-do neighbourhood put down their names as willing to have their houses electrically lighted, the thing is done. In the United States even the little towns have their central lighting stations, and they pay. There are several on the Continent also paying. It is in connection with central station lighting that the future of the new illuminant lies, and we predict that it will not take long to prove that that future will be as bright as electricity can make it. John Bull was ever cautious and suspicious of new ways. He didn't believe in gas at first. He didn't believe in the Suez Canal. But he always accepts accomplished facts, and has an eye to an investment which is proved to be a paying one. He has been scared by the mad boom in electrical shares and the subsequent collapse, and is, not without reason, coy; but let him see dividends being paid by central lighting syndicates and companies, his bashfulness will vanish, and he will bestir himself and kiss the rising sun. Fortunately, even among us phlegmatic islanders have been found men with a stomach for adventure, who have been willing to go into untrodden regions; and we trust these bold spirits will be amply rewarded for their enterprise.

We are watching with great interest the race for provisional orders. The knowing ones, the good old promoters of the recent past, have entered for a large number, and herein lies the danger. History repeats itself, and we cannot but fear that imprudent speculation and company-mongering may do much harm to the industry. While welcoming every solid and necessary undertaking, and seeing in such a legitimate opening for capital with the chance of very good dividends for the investors, we would suggest to our readers that they should carefully scan the prospectus for the names of old offenders, and to see that the directors are those who will be likely to work in the interests of their companies only. We also advise their ascertaining that there is a real want for the light in the localities which they intend to serve, and that the system to be adopted is economical.

UNDERGROUND WIRES.

THE schemes for electric lighting, which are on the verge of springing up in all directions, seeing that 400

[DECEMBER 20, 19

at least are to come before Parliament next year, w probably result in the much vexed question of une ground conductors being solved in more ways one, and will also occasion numerous patents be taken out for, so-called, new ideas in connect with the same, most of which, however, will be o signed to oblivion. For low tension systems the tion will not be a difficult one, but even here the essentials to success are good manufacture, good sup vision, and good scientific advice. The latter is often ignored, with the result that instead of a sar being effected imperfect work is laid down, wir causes constant trouble and endless expense. We ta over and over again asserted that underground work fr electric light purposes should be as carefully done a the case with submarine cables, and we again s that this should be so. Important as good work is low tension systems, it is vastly more so in cases whe high tensions are to be used, and should the latter cointo extensive employment a radical change will b to be made by manfacturers in their system of testi the wires. The present method of testing with a b voltage obtained from small sized cells will have be abandoned for, or rather supplemented by, system of testing in which high voltage dynam are employed, not occasionally, but as part of t regular system of manufacture. In favour of the bay wire system there is much to be said; for low volta there is little reason why it should not prove successi but success depends, we believe, on a system of a ficial ventilation of the conduits being adopted so a clear out and prevent the deposition of moisture. Th has been suggested more than once, we imagine, but in no case does it appear to have been carried out. Probab the best system of all to employ, though a comparative expensive one, is a combination of the two, i insulated wires laid in conduits, so that no dire digging up of the cables is required in order to rep faults, and no injury by pickaxes or punners is like. to take place.

We are told that Mr. Price, of the well-known fr of electrical auctioneers, has convened a meeting of t trade for the purpose of advocating a general rise prices of electrical plant-we mean the apparatus, the journal of that name. In discussing the mat with a friend, we were assured that the best mode effecting the object which has evolved itself from V Price's fertile brain would be for his firm to cast i its second-hand appliances into the sea.

OUR infallible friend in New York, the Electres. Engineer, falls foul of Mr. Edison's assertion that th is no known insulation which will confine the hi tension currents for more than a limited period. As matter of fact, says our contemporary, whose leani towards a well-known high tension alternating currai system is an open secret, the allegation is not tr We fancy that Mr. Edison's meaning has not be exactly grasped, for everybody, including the "Wiz of Menlo Park," knows that wires can be thorough insulated for the purpose; but at what cost? It see

DECEMBER 20, 1889.]

kely that Mr. Edison intended to convey the imression that wires carrying a current under an ternating E.M.F., of, say, the Deptford standard, could ot be insulated for a permanency at a price which hould not be considered prohibitive, and in this we ink the famous inventor will eventually be found >rrect.

A NEW electric brake, the invention, we believe, of rofessor Forbes and Mr. I. A. Timmis, has been tried 1 the London and North Western Railway. It acts in 1 entirely different manner to any other now in use, the retarding effort is not applied to the periphery f the wheel but to its inside face, or rather upon an on disc fitted to it. The experiments made in opping carriages running at thirty and forty miles an our were eminently satisfactory, and the oscillation and umping which one so often experiences when the rake is applied seem to have been conspicuous by heir absence, or at least only slightly appreciable.

THE news comes from New York of another death rom contact with an electric wire. From the public oint of view it is even more alarming than those preeding, as it is considered difficult of explanation. A ireman named Sullivan, employed by the Manhattan Electric Light Company, turned a steam valve, while arrying a 16-candle incandescent lamp in his left and. At the time Sullivan was working alone. When he next person entered he was found quite dead. The urns on his body showed that the current had passed hrough him from the left hand to the right ear. occasion of the alarm is that it is supposed the man was killed by a current under an E.M.F. of 120 volts. We cannot, however, reasonably accept this theory. The more probable assumption is that the death-dealing current came from a high tension electric light wire which by some means came into contact with the one held in the hand.

The

KESWICK, a small town of 3,000 inhabitants in the Lake District, may be congratulated on its manifest spirit of progress. The electric company which was Formed in the early part of the present year has already done good work. Many customers are applying for the light, and about Christmas there will be a full supply of the current turned on. The light will be measured to the consumers by meter, and it is estimated to cost a price equivalent to gas at about 3s. 6d. per 1,000 feet, which is about 9d. per 1,000 less than the actual cost of gas in Keswick.

THE opposition of the Exchange Telegraph Company to the granting of a patent to Messrs. Wright and Moore, for a column printing telegraph instrument, which was heard before the Comptroller of Patents on Monday, ended in favour of the Column Printing Syndicate. All the objections of the Exchange Company were abandoned except one, which appears to be of a trivial nature, and the patent will accordingly be issued to Messrs. Wright and Moore. Mr. Moulton, Q.C., characterised the objections as being so frivolous that he felt sure his learned friend, Mr. Graham, who appeared for the Company, would not attempt to defend them in Court.

No longer will the subscriber to an American Telephone Exchange, in answer to his ring-up, be greeted with the familiar and expressive "hollo!" from the

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cheery lips of the deity who presides at the Exchange. The word has been banished from the sacred precincts. Perhaps, as the word is generally pronounced "hello," it may be considered to savour too much of the profane, and to suggest a desire to communicate with a far land with whose inhabitants angels should have nought to do.

THE Julien Company states that the new batteries, employed in propelling tramcars in New York, show a fall of potential of 10 in a run of 12 miles, against a loss of 30 in their old form.

A CORRESPONDENT writes :-"I have read through the article about Flood Page's scheme. It is, as you say, absurd, especially the examination part. I would undertake to set an examination paper which would stick every Professor on the Council of the Institution of Electrical Engineers, and I am perfectly certain each of them could set a paper which would stick me. Who, then, shall set the questions? Is he to be a practical or theoretical man, or is it to be the Council? The members of the latter would certainly be plucked. Imagine one of them setting down to answer, What is a watt? How do you measure power? What do you understand by the specific resistance of a rabbit skin? Do you consider it safe to sit on a barrel of gunpowder while embracing in a thunderstorm a lightning rod? &c., &c."

THE tests of the Eiffel tower lightning conductors given in our present issue, though they show that the conductors themselves are in good condition, are hardly conclusive as to the goodness of the earth connection. We are aware that the method of testing employed is one which is very generally used and which is considered to be satisfactory, but it really does not prove that the earth is good, i.e., that the lightning has a perfect path to escape by. What is really proved is that the mass of soil in which the conductors are imbedded conducts well. If we could imagine the whole mass of earth to be enclosed in an insulated rocky basin, it is evident that the tests obtained would still be practically the same as those observed, but it could hardly be argued that the lightning would therefore have a free path along which to dissipate itself.

THE New York Electrical Engineer in its last number says, in defence of the high tension alternating current transformer system :-"There is not a solitary instance on record of a consumer having been killed, or even injured ever so slightly, by the alternating current, as a 50-volt current, incapable of harming a child, is the maximum which is allowed to enter a consumer's premises." Yet it is possible that the primary and secondary wires of the converter may not always be safely separated, as witness the Standard's telegram in our other columns, for in what other way can we account for the result? Captain Cardew might dilate on this circumstance to some advantage, for the fact of having patented an "earthing device" must have made it manifest to his mind that such accidents as this latest American fatality seems to indicate, were always liable to occur. Is it not high time that measures are taken in this country to reduce to a minimum the dangers of alternating current systems?

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CONTACT ELECTRICITY AND THE CHEMICAL THEORY OF THE GALVANIC ELEMENT.

NEARLY a year ago, it may be remembered, there was an interesting paper in the Zeitschrift für Physikalische Chemie, contributed by W. Ostwald, which consisted of a detailed account of a series of experiments which were undertaken by him in order to ascertain the difference of potential between certain metals and solutions. These experiments were carried out by means of dropping electrodes of mercury.

The differences of potential investigated were those between the metals-zinc, cadmium, tin, lead, iron, copper, bismuth, silver and mercury, and aqueous solutions of the following acids :-namely, hydrochloric, hydrobromic, hydriodic, nitric, sulphuric, phosphoric, formic, acetic, oxalic and benzoic. In the original paper all the results are tabulated.

In prosecuting this research Ostwald experienced considerable difficulty in eliminating the difference of potential between the mercury electrodes themselves and the solutions. He endeavoured to overcome this difficulty by adjusting the aperture from which the mercury issued, and regulating the flow of mercury, but although the source of error was minimised it was never got rid of.

The difference of potential between a metal and an acid depends upon the nature of each, though probably that of the metal has the more marked effect.

In Ostwald's experiments zinc and cadmium were found to give negative results, whilst copper, bismuth, silver, antimony and mercury yielded positive results; tin, lead and iron, however, afforded both positive and negative values of the potential difference.

The effect of the nature of the acid is exemplified in the results with the haloid acids. The difference of potential is generally smaller. The solutions used by Ostwald were normal, deci-normal, and centi-normal, and he observed that dilution increased the negative and diminished the positive potential.

If the difference of potential between these metals and acids be compared with the heat developed when they act upon upon one another chemically, a striking resemblance is at once noticeable, showing that the order of these values is somewhat similar. When, however, assuming that chemical energy is entirely converted into electrical energy, the difference of potential is calculated from the heat value, the result is found to be very unsatisfactory. This seems to indicate that the assumption cannot be upheld. The investigation of this difficult but attractive subject has more recently been continued by F. Exner, whose papers on "Contact Electricity" in the Monatshefte für Chemie und Verwandte Theile anderer Wissenschaften are well known. In his researches on the theory of the galvanic element he has been assisted by J. Tuma. They recently contributed a paper to the Monatshefte (vide IX., pp. 903-943), in which the weak points in Ostwald's work are discussed, and several sources of error suggested which he seems to have overlooked.

Exner and Tuma consider that dropping electrodes of mercury produce untrustworthy results, because of the chemical action of the electrolyte upon the mercury and the subsequent occurrence of polarisation. Thus, in the case of dilute sulphuric acid, the chemical action of the electrolyte was found to produce a marked difference in the result, equivalent to 0.84 Daniell, while the polarisation produces an effect varying between 0.8 to 1.2 Daniell.

The work of J. Moser on the resolution of the electromotive forces of galvanic elements into their differences of potential (vide Monatshefte, VII1., 508-509) is exposed to the same criticism. The same may also be said of the researches of J. Miesler on the resolution of the electromotive forces of such galvanic elements as the Marié-Davy, De la Rue, and Niaudet.

Messrs. Exner and Tuma believe that these sources of error may be eliminated by an arrangement which briefly described as follows:-The mercury is rop into a cylinder of filter-paper wetted

may

al

[DECEMBER 20, 189.

with the acid solution in which the metal under ex nation is immersed, and the cylinder is connected wi the acid bath by means of a thread similarly wettel A series of metals and acids were examined b means of this arrangement, and in every case, er that of platinum with carbon in concentrated ar acid, the metal was found to be negatively charg Probably this exception was only apparent, and ar have been due to the formation of nitrous acid in t solution.

Messrs. Exner and Tuma further showed that 2. values of the potential differences of the metals in metallic salts of the acids were the same as those vai of the metals in the same acids.

Ostwald has recently replied to these criticisms in short paper in the Zeitschrift Physik. Chem., I pp. 354-358. He endeavours to substantiate his s sults, and points out that they agree with those obtainfrom observations of the maximum surface-tens The statement that chemical action and polarisati occur is questioned.

This subject has now assumed a controversial asper and it would be premature to attempt to sum up at pre sent; all that can be done here is to indicate the new of these different physicists, so that others may attracted to lend their energies to the elucidation of extremely interesting problem.

ON AN ARRANGEMENT OF THE PRONY BRAKE, INTENDED FOR THE EXACT VALUATION OF MOTIVE COUPLES.

By M. HILLAIRET.

THE greater number of absorption brakes used i industry for estimating the work of machines pres the same general arrangement, and the motive momentum is counterbalanced by the momentum c a force that is almost always single, and acting on one side only of the brake pulley. At the time when t force brings into equilibrium the motive effort, it giv rise to a translating resultant of the same magnitat and direction, which acts upon the bearing of th axle, so as to press more or less upon it according circumstances. This parasitic action of the moti axle upon its bearings gives rise, upon contact with the rubbing surfaces, to a variable effort, the moment of which detracts from the apparent value of t motive effort, so that the work estimated upon the brake represents only the motive work, minus the work of the friction mentioned above.

Now, the latter is essentially variable as it is proper tional 1. To the variable charge of the brake; 2. T the coefficient of friction of the surfaces in conta which itself varies according to the lubrication. It impossible to estimate it exactly at each moment during a series of trials. We are thus generally compelled t leave out of our calculations an item, the value of which may in certain cases amount to 4 or 5 per ce of the quantity to be measured.

Having recently had to make some very exact test in order to determine the gross mechanical renderi of an electrical transmission of 500 H.P., I directe my efforts to the elimination of this parasitic work endeavouring to realise a resistant couple that woall bring the motive couple into exact equilibrium, so a to suppress any resultant of translation.

The arrangement of the brake (Comptes Rend with a couple thus obtained is shown in the diagra below.

It will be seen that the counteracting effort is ch tained by means of the spring of a steel-yard sprin balance.

Although the employment of the steel-yard brake measurements is not new; it is worth whito remember that it greatly facilitates trials fr lowed by variable powers, the tightening of the coli

REVIEW

eing sufficient to make the effort vary. Besides the actness that this arrangement gives in valuations, we ay also mention the absolute security resulting from s employment, the ensemble of the scale beams and ds being firmly fixed in their position, and the course the spring being only a few thousandths of the ngth of the lever arm, M N.

O, motive axle ; A K B, collar of the brake; V, flyheel for tightening the collar; CE, beam oscillating om the fixed point, D; C A, E F, attaching rods; B F, upling balance; G L, connecting rod; L N, lever for educing the efforts oscillating at M; P, spring-balance.

was 24 kilogrammes, and that of the lever, L N, was given by the preliminary displacement of the spring balances when empty, and amounted to 15 kilogrammes. The collar being greased and the rim wetted on the inside continuously, the tests were able to be prolonged during several hours.

The maximum work, as estimated by this method, was 300 H.P., with an angular speed of 240 turns per minute.

Since the end of last September the Chevrant works (paper manufacture) have been supplied with power by an electrical transmission effected by means of two machines, generator and receiver, separated by a distance of 5 kilometres. The generator, having a maximum power of 300 H.P., is driven directly by a turbine of the same power, making 240 revolutions per minute, and receiving the water of a fall of 70 metres, drawn from the stream called the Domenon, and turned into a channel lined with steel plate, 700 metres long. The receiver can, at its maximum, develop 200 H.P. at the rate of 300 revolutions per minute.

The two dynamos are connected by a line formed of two cables of naked copper, with a section of 50 mm. The transmission is working day and night, with two intervals of rest of 20 minutes each, morning and evening.

The turbines and the relays of steam engines, the place of which is intended to be supplied by this transmission, are stopped, and the corresponding boilers extinguished. The principal electrical data of the transmission are the following:

ELECTRICAL RANGE FINDER.

Of the many valuable inventions in modern warfare, says Modern Light and Heat, which have emanated of late from Lieut. Bradley A. Fiske, United States Navy, perhaps none is more worthy of consideration than his recently patented apparatus for finding the range and position of distant objects through the agency of electricity. For some time past secrecy has been maintained regarding the details of this device, though it has been known in well-informed naval circles that such an apparatus had either been or was about to be patented, and that its salient features consisted in the determining of the exact range of any distant object by keeping trained upon it a telescope, which in moving carried along with it a dial parallel with the telescope. This dial, it was understood, had electrical contact with a graduated arc over which it moved, and by means of ranging angles registered accurately the distance of the object from the apparatus during all varying stages.

By the means of a simple train of a telescope Mr. Fiske proposes to know at all times just how far away is the position of the enemy, and from thus knowing that position, accurately to impart the information to the batteries and secure a sight adjustment that is absolutely correct. This, in brief, is the underlying principle of the " 'range and position finder; to what further practical uses it can be applied will be seen from the description, but that it is a success is undeniable, and the chances are that with the thorough practical tests to which it will be subjected on board the flagship Chicago, where the first apparatus has been placed, it will be found essential for accuracy of firing on all the new ships.

There is

The invention of the "range and position finder," as Mr. Fiske puts it, consists in the determination of a fractional portion of a conducting body bearing in length a ratio to the angle included between two lines of sight directed upon some distant object, and the measurement of the electrical resistance of said length. The electrical device consists of an ordinary Wheatstone bridge with its four members, in one member of which is arranged a body of conducting material in arc form and a movable arm traversing this arc. also the transverse member, in which is connected the galvanometer. A battery is connected to the bridge in the usual way. In two of the members are placed fixed resistances, and in the adject member to one containing the arc form is a variable resistance placed as usual. One wire from the battery connects to the end of a member containing a fixed resistance, and at the same time to the pivot of the swinging arm which plays over the arc form. The extremity of this pivot arm moves over and maintains electrical contact with the arc form of conducting material, which latter has one extremity connected to a member of the bridge. Now, when the point of this arm is brought in contact with the member having connection with the arc form, the dial at that moment is in prolongation of this member, and the pivot of the dial having wire connection with another member, there will at once be a current traversing directly from member to member instead of, as before, through the medium of the intervening arc. Now this arc form is made of such material and so proportioned that its electrical resistance to a current traversing it is proportional to the length of arc included between the point of the dial and that part of the arc having contact with a member