132

unnecessary. The salaries at the stations are £273 higher, owing partly to some little increase which it has been necessary to make in the pay of the operators, who have had no advancement for some years past. Maintenance and renewals of instruments cost £250 extra, principally by reason of the adoption of the recorder instruments at our main cable stations, and from which satisfactory results have been obtained; travelling expenses, repairs and renewals, I believe, show a reduction of £35 and £32 respectively. With the exception of the expenses connected with the action of the Anglo Company and the French Company, which is quite of a special character, the remaining items of expenditure are practically unaltered. On the 19th April last the main cable was broken on the Green Bank by a ship's anchor. The Telegraph Construction Company's screw steamer was at once despatched to the position of the break, and the cable was restored on the 19th May, the total cost, including the cable used, was £4,474 18. 11d. A portion of the cable taken up during these repairs was found in excellent condition, though it has been submerged 16 years (this was afterwards placed on the table). The reserve fund account, after being credited with interest on the investment and profits and sales of securities, and debited with cost of repairs, now amount to £242,048; it is on this occasion proposed to further increase the reserve fund. The cables have cost a considerable amount during the last twelve months. I have a letter, received this morning, from Dr. Muirhead, in which he refers to the tests recently taken of the main cables, and he says he has no hesitation in saying that they are practically as perfect to-day as they ever were. As you are aware there was a time when we believed that ten years was something like an average life of a cable, we can now say it is more like twenty years. I think that shows you that we are perfectly satisfied with the present position of our cable. After briefly referring to the shilling tariff and the lawsuit, which he considered was going on satisfactorily, the motion that the report be adopted and the dividend paid was carried.

The names of Sir H. Keppel and Admiral Mayne were then put before the meeting for re-election as directors, which was carried, Mr. Guesden showing his disapproval by voting against it.

The auditors were then re-elected, and the meeting closed with the customary vote of thanks to the chairman.

United River Plate Telephone Company, Limited. IN the report of the directors, to be presented to the shareholders at the third ordinary general meeting, to be held at Winchester House, 50, Old Broad Street, E.C., on Thursday, the 8th August, 1889, at 12 o'clock noon, the directors beg to submit to the shareholders the accompanying balance sheet and profit and loss account, showing the result of the company's operations during the year ending 31st March last.

That result, after paying all working expenses abroad, debenture interest, London and other charges, is a profit of £32,850 133. 10d., from which has to be deducted the sum of £14,689 63. 8d. for loss on exchange, leaving a net profit of £18,161 7s. 2d., increased by the balance of £1,666 23. 6d. brought forward from the previous year, to £19,827 93. 8d.

Out of this an interim dividend of 3 per cent., or £8,250, was paid in January last; and the directors recommend that out of the remaining balance of £11,577 98. 8d., a further dividend of 3 per cent., or 33. per share, free of income tax, be now paid, which absorbs £8,367 23. 6d.; that £2,000 be placed to the depreciation and renewal fund, thereby increasing it to £7,000; and that the balance of £1,210 7s. 2d. be carried forward to the credit of profit and loss account for the current year.

The directors record with satisfaction that the 5,000 new shares referred to in their last report, and offered to the shareholders pro rata in August last, were readily subscribed for, and the shareholders will observe that the capital expenditure during the year amounted to £35,070 2s. 11d., which, however, includes the purchase of the additional business at Rosario, mentioned in the directors' last report, and to meet the cost of which, 3,000 shares were issued to the vendors, the share capital issued being thereby increased to £290,000, as shown in the balance sheet. With this purchase, and the amalgamation consequent on it, the company's business at Rosario is fully consolidated; and the further capital expenditure during the year has placed the company's whole system in the Argentine Republic on a sound and efficient footing.

The directors have pleasure in pointing out that, as shown by the figures in the balance sheet and profit and loss account, the business of the company has steadily and considerably developed and increased in the past year, the gross receipts in the River Plate for the year having been £81,866 28. 4d., as against about £66,092 for the preceding twelve months. The net results, however, have been affected by the loss in exchange, an item absolutely beyond the company's control, which amounted to £14,689 63. 8d., as against £10,775 198. shown in the previous balance sheet. The directors are now considering the advisability of adopting measures in some degree to meet this loss in exchange; while they are glad to say that the reports received from Buenos Ayres since the 1st April continue to show a steady increase in the company's receipts.

In accordance with the understanding at the last general meeting, Mr. George Cooper and Mr. Alfred Le Rossignol joined the board, and have since given the company the benefit of their experience in the River Plate.

Under the articles of association, Mr. Frank W. Jones and Mr. Thomas Lloyd retire by rotation at this meeting. Mr. Jones, being eligible, offers himself for re-election, but Mr. Lloyd does

[AUGUST 2, 1889.

not seek re-election. Major Henry Fitzgerald has also resigned, and, while the board have received Mr. Lloyd's and Major Fitzgerald's resignations with great regret, recognising their services to the company, they do not propose any other gentlemen to take their place, as the board will thus be reduced to the original number of seven, which reduction, as explained at the last general meeting, has been for some time contemplated.

The auditors, Messrs. Cooper Bros. & Co., also retire, but offer themselves for re-election.

N.B. If the dividend herein recommended be approved at the meeting on 8th proximo, the warrants will be posted to the shareholders that evening.

The Telephone Company of Austria, Limited. IN the report presented at the sixth ordinary general meeting of the company, held at the offices of the company, 53, New Broad Street, on Wednesday, the 31st July, 1889, for the year ending 31st March, 1889, the directors state there has been expended on capital account a further sum of £8,546 53. 10d. The gross receipts from all sources were £13,969 6s. 5d. After providing for all expenses, including £3,604 10s. 6d. for debenture interest and preference dividend, and £2,206 93. 10d. for royalties and taxes to the Austrian Government, there remains a net profit of £2,352 103. 5d., which, with the amount, £931 143. 1d., brought forward from last year, leaves a balance to the credit of profit and loss account for the current year of £3,284 43. 6d. ; this amount it is proposed to carry forward.

There is a continued increase in the number of subscribers to the company's exchanges, as shown by the following table:

Installations in the towns are still progressing at the usual rate, and so far as the board can judge, seem likely to continue to do so. The calls of subscribers now average over 64,000 per week, as against 60,000 last year.

The Austrian Government having decided to run a trunk line from Vienna to Prague, your directors are now erecting, at a very heavy cost, a new and improved switchboard at their Prague exchange, to correspond with the system in use in Vienna. This expense was undertaken in the first instance with the view of assisting the Austrian Government in their endeavour to carry out successfully their scheme of inter-urban telephony, but will also become a productive outlay as increased and improved switchboard accommodation will, in a time not far distant, become necessary, owing to the constantly growing number of subscribers in that city.

The question of the prolongation of the company's concessions is now under the consideration of the Government, a very carefully considered petition having been laid before the Minister of Commerce, and it is expected that the matter will be decided this

autumn.

The transmission and delivery of telegrams by the company's exchanges has very considerably increased during the past year. the number of messages dealt with averaging 2,150 per week, and although this service has not yet proved remunerative to the company, its advantages indirecty are very great, and sufficient to justify its continuance.

Tas cordial and satisfactory relations of the Imperial Royal Government Telegraph and Postal Authorities and municipal bodies with the company remain unaltered.

It is with regret that the directors have to announce the retire ment from the Local Board in Austria of Mr. Joseph Wessely, owing to ill-health. The thanks of the shareholders are again due to him, and very specially to Dr. Eugen Weissel, for their continued services during the past year, as also to Mr. R. Howard Krause for the highly satisfactory manner in which he continues to perform his duties as general manager.

Mr. C. L. W. Fitz-Gerald retires by rotation from the board, but being eligible, offers himself for re-election.

The directors, to meet the wishes of the Consolidated Telephone Construction and Maintenance Company, Limited, have invited Mr. Joseph Hicks Buckingham to a seat on the board, and will propose his election accordingly.

The auditors, Messrs. Deloitte, Dever, Griffiths & Co., also retire, but being eligible, offer themselves for re-election.

The meeting was held on Wednesday, but our representative not being admitted we are unable to give a report of the proceedings.

TRAFFIC RECEIPTS.

The Brazilian Submarine Telegraph Company, Limited. The traffic receipts for the week ended 26th July, 1889, amounted to £3,163.

The Western and Brazilian Telegraph Company, Limited. The traffic receipta for the week ending 26th July, 1889, after deducting the fifth of the gross receipts payable to the London Platino-Brazilian Telegraph Company, Limited, were £1,697.

* Exclusive of 142 " Extension" telephones, which were erected during the year, giving an additional annual rental of 4,510 fl.

AUGUST 2, 1889.]

ALTERNATE CURRENT WORKING.

THE following is the text of Mr. Mordey's reply to the discussion which took place on his paper read before the Institution of Electrical Engineers on May 23rd, reprinted from the proceedings of the Institution.

Mr. W. M. MORDEY said:-I wish in the first place to express my thanks for the very kind way in which you have received this paper. The criticisms have, in some cases, been answered by other speakers. The remaining points in regard to which the speakers are not in accord with me I must deal with so far as I can in the time at my disposal, but I need not occupy time by referring to other matters.

Dr. Hopkinson's statements on electrical subjects are always received, not only with great respect, but as being usually correct and final. I join in the respect, but venture to question the correctness in this instance. If Dr. Hopkinson would be better satisfied by my stating that the most perfect alternator conceivable is one which has an indefinitely small self-induction aud resistance, I am quite prepared to express my meaning in that way. I was acquainted with the general practical results, as regards parallel working, brought before us in 1884 by him, but, for reasons which will be understood, I did not derive any assistance from his theory, nor do I now agree that that theory "is sufficient to predict all the results obtained." I cannot fully argue this point, but must ask Dr. Hopkinson if he will kindly look into it again, for I am strongly of opinion that he will find that it is not as complete as appears to be supposed. I am the more convinced of the correctness of my explanation by the measurements of the self-induction of my armature by Prof. Ayrton's assistants, using the new Ayrton and Perry instruments, and by the statement made by Prof. Ayrton that the time-constant, or ratio of the self-induction to the resistance, was about the same in my machine and in that of an alternator of another maker, which latter machine only exhibited very feeble synchronising properties when attempts were made to run two of them in parallel.

The point where mathematical treatment of the subject appears to have failed is that it has not taken sufficient account of the "stiffness " of the field. This is at once apparent when this measurement of the self-induction of one of my machines is referred to, from which it will be seen that the self-induction was practically the same whether any impressed field existed or not. Manifestly, with no impressed field, the controlling power of the machine would be quite inconsiderable, although the values of self-induction and resistance-upon which Dr. Hopkinson relies-would be the same then as when the machine was working with a strong impressed field and under the conditions giving the maximum generating and controlling power. Hence it is evident that a theory which only takes cognisance of self-induction and resistance must be altogether illusory.

There are several reasons for the view that his theory is incomplete. His paper has been before the world for several years, and has been often studied, but neither its author (who has been engaged on the subject) nor anyone else has ever based any practical advance on it. Working parallel has been recently considered, as a question of great urgency and importance, before this Institution and elsewhere, and there have been abundant opportunities for bringing forward any useful information, but the whole subject was misunderstood; and Dr. Hopkinson, who has been a witness of the struggles that on all sides were being made towards a better understanding of it, has remained silent. I am sure that nothing would be more unlike him than to let the whole industry suffer for want of a little clear and definite information, if he had been able to give that information. Dr. Hopkinson even took part in the discussion on Mr. Kapp's paper a few weeks ago, and threw no light on this question, thus tacitly subscribing to the current views.

It would be easy to find several other instances, besides those mentioned in the brief enumeration in my paper, to show that the views generally held were entirely misleading and incorrect. For example, Mr. Swinburne alludes to* Dr. Hopkinson's mathematical treatment, and says that he has put the matter into English in his book; and I find in that (recently written) book it is stated (on p. 151) that there are no alternate-current motors. But nothing less than the actual words can show how completely misleading this theory was. Mr. Swinburne proceeded, in the book in question: "It seems generally to be assumed that the only difficulty with alternating current motors is to start them. It seems probable, however, that there will be very great difficulty in designing a motor which will work with reasonable efficiency and varying load. An alternating is a widely different thing from a direct current motor."

Having seen all these statements disproved-having seen a 50 H.P. synchronising motor running with high efficiency under varying load, and designed on the lines of a direct current motorMr. Swinburne now comes forward and says: "I see nothing in Mr. Mordey's interesting experiments which conflicts with the recognised theory; in fact, the position of synchronous motors is not altered "the italics are mine. Truly the Hopkinson theory, as rendered into English, must be capable of infinite elasticity. Then again, only a few months ago, Mr. Swinburne, who had assimilated this theory, stated that such machines as mine would

The Electrician, June 14th, 1889, p. 154.

+ Practical Electrical Measurement."

The Electrician, June 14th, 1889.

1 Journal, vol. xvii., p. 401.

133

not run in parallel at all, and he described an "inductioncoupler" which he had devised for the purpose of making them so run by inserting self-induction. That device is a very good illustration of the results of the old theories. I may mention that when I was labouring in the slough of those old theories I independently devised that identical arrangement, which is one quite in accord with the requirements of those theories, so far as I was able to understand them; and having entirely failed to get two ironless alternators of a well-known type to work parallel in their simple condition, I tried that "induction-coupler without any improvement in the result. That was, in fact, one of the experiments that opened my eyes to the whole fallacy. It helped me to see that anything that prevented the instantaneous passage of the necessary correcting current must inevitably tend to prevent synchronous action.

Referring to Prof. Adams's criticism, I may say that I was fully aware of his experiments at the South Foreland Lighthouse, and referred to them. Prof. Adams considers those experiments as conclusively establishing Dr. Hopkinson's theory. I need not again consider them in that connection, but would only say that the motor effects obtained were not powerful, and that they have not been taken as forming a basis for practical construction. Indeed, they have remained on record as the not very high tide-mark beyond which no substantial advance was found practicable, until machines having very different qualities were developed. It would cause me no surprise to find that the South Foreland experiments succeeded from quite different causes than those imagined by Prof. Adams. It is not at all clear that any of the advocates of Dr. Hopkinson's theory really understand what that theory is. It seems to cover a multitude of quite opposite interpretations, and resembles some of the Hebrew prophecies in its comprehensive applicability to occurrences-after the event. Prof. Adams, I am afraid, rather supposes that I make some sort of claim to having introduced parallel working. The object of the first portion of my paper was rather to state what lines I thought should be followed in order to obtain the best results, and to show that on those lines complete success could be attained at a time when, in spite of Prof. Adams's well-known and valuable paper, considerable and well-founded doubt existed as to the commercial possibility of parallel working. In one respect, however, I am quite unable to follow Prof. Adams, and that is in some of his analogies between alternators working parallel and tuning-forks vibrating in unison. He says that I gave the octave when I had one machine working at 1,000 volts and the other at 2,000 volts, both being at the same speed, and he suggests that I should give the double octave, and various other ratios. Now I fail to see that there is any true analogy between various rates of sound vibration produced by tuning-forks and corresponding ratios of electrical pressure. It would be just as correct to say that a steam boiler with a pressure of 120 lbs. on the square inch was giving the octave of another boiler working at 60 lbs.

As to the very different problem of running alternators parallel when the alternations are an octave of one another-a possibility that is also put forward by Prof. Adams, and which has been inentioned to me by Mr. Sumpner and others-I can only say that I have not tried it, partly because it does not hold out any promise of a useful result if successful, and partly because I feel pretty sure it would not succeed, except with machines having so inuch self-induction as to render them unsuitable for practical purposes. A little consideration will, I think, show that this must be the case.

Prof. Adams refers to the loud humming noise made by my alternators when they were connected parallel while out of phase as very sufficient evidence of very considerable self-induction, in consequence of which the speed of one machine is suddenly increased, and of the other as suddeniy diminished." This noise is really a proof of the contrary. It is caused by the enormous rush of current which the comparative absence of self-induction renders possible, and this momentary rush puts the machines in phase with a jerk. As bearing on this point, I may mention that some machines that are said to have large self-induction do not make this noise under the same circumstances. Their self-induction prevents any such rush of current, and, according to my view, also prevents their working parallel. Although dissenting from my explanation, this rush of current is recognised by Mr. Swinburne (p. 656) as a proof of absence of selfinduction.

It is interesting and important to consider another action arising out of this matter. In several machines-some with and some without iron-the self-induction is so serious that it does as well to short-circuit ar nature coils as to cut them out when it is desired to reduce the potential difference at the terminals. In fact, these machines cannot be injured by accidental or intentional shortcircuits. They obtain this advantage, however, at the cost of every other good quality. The rush of current, the effect of which Prof. Adams noticed, but misunderstood, in my machine, could not take place with such high self-induction machines. They could be put into connection when out of phase, and would simply choke back the current which attempted to put them into step.

I think there is no real difference of opinion between Major Cardew and myself on the subject of safeguards. I quite agree with him that the two contacts, a and b, may be "ready waiting for a person to make the other two contacts and so receive a shock. It is to prevent the possibility of this that I so strongly recommend earthing. It is an absolute safeguard, costs nothing, and does not cause interference with telegraph or telephone service. I cannot admit that it increases fire risks. I think it lessens them,

134

because it makes it certain that a faulty transformer or house cir cuit cannot remain on. The safety fuse on an earthed circuit instantly cuts off a faulty house, and so prevents that gradual accumulation of unsound or actually defective places that, without some such safeguard, would soon render a large supply service unworkable. As to the supposed excessive strain on a 100-volt circuit if it is earthed, that does not exist in practice. The secondary is earthed in the middle, so that the strain is really only 50 volts; and an installation that will not stand that strain is radically bad and ought not to be allowed anywhere. The great advantage of earthing is that it secures safety, protects the customer against bad work and leakage through his meter, and protects the system against the presence of rotten installations. If the fire offices do not see before long that earthing does not increase fire risks, I shall be greatly surprised.

One or two points in Dr. Fleming's remarks require some reply from me. His suggestion to account for the behaviour of transformers with different periodicities is, I think, very pretty and very ingenious. At first I could not fully accept it, as the greater penetration of the eddy currents into the iron at a low periodicity seemed to be an effect that would not be likely to be felt with very thin conductors, such as the laminated iron (see under "Conductors"); but I now see that the currents in the laminations, although very close together and insulated from each other, can act on one another and produce the "virtual resistance" effect.

I

Prof. Fleming's objection to my substitution of the word " magnetisation" for "induction" is not a very strong one. have only to say that I think "induction" would not be a good word even if it had not already been secured for a dozen other purposes. Some limit should be placed to the multiplication of meanings given to this one word, which, after all, is not an electric or magnetic word at all.

Mr. Kapp has latterly given much attention to this subject of alternate current working, and understands its difficulties. On this account, and also because I was obliged to strongly oppose some of his views, I highly appreciate his kind remarks about the paper. He accepts all my facts, but rejects my interpretation. He will, I feel sure, accept them both on further consideration.

The experiment of which he suggests an explanation, which is in some respects similar to the explanation proposed by Sir William Thomson, is no doubt a very interesting one. It is a case not very likely to occur in practice, but deserves attention. I do not, however, quite agree with Mr. Kapp and Sir William Thomson. I wish their explanations were more convincing, and were not so much opposed to Prof. Ayrton's measurements of the self-induction with different relative positions of armature and field, and with various field strengths, which showed that the actual conditions are exactly the reverse of those relied upon in Mr. Kapp's supposition.

I think that in any case the actual magnetising or demagnetising action exerted by the armature on the field magnet must be small, partly for the reason, pointed out by Prof. Silvanus Thompson, that there was not time in a half-period for the solid iron to undergo any change, and partly because the armature is purposely made so as to exert as small an effect of that kind as possible. The machine consists of a very powerful electromagnet, the field; and a very weak electro-magnet, the armature. Even if coils similar to the armature coils were wound on the extremities of the polar horns, and had a direct current sent through them equal to the maximum working alternate current, they would not produce a very powerful effect on the field.

One of the difficulties met with in considering this question is that there is no means of knowing which machine was generator and which motor. This depends, of course, upon the relative power of the engines. It is quite possible that the lower E.M.F. machine was acting as the generator.

I can only say that I will take the first opportunity of acting on Sir William Thomson's suggestion as to testing the supposed changes of magnetisation, and hope thus to be able to settle this question.

Mr. Swinburne challenges my conclusions on several points with his usual vigour, and I very willingly take up the gauntlet. I have already alluded to some remarks of his which place him in the honourable light of an interpreter of Dr. Hopkinson's mathematics. The position is one that requires great powers of endurance and considerable courage.

Mr. Swinburne says that electrical engineers do not realise what is wanted in parallel running." I accept this candid statement as, at any rate, quite correctly describing his attitude in the matter; and am, therefore, of course, prepared to find that he disagrees with most of my views.

He commences by stating that so far from the motor being kept in step because its self-induction was small, that, if there were no self-induction, the generator would have no control at all over the motor.

This is an instance of a very common mistake-that of supposing that if there is practically no self-induction there can be no generating or motive capability. The exact contrary is the case, as I tried to explain in the paper when I expressed the view that a perfect alternator for any and every purpose should have no resistance and no self-induction" (page 591). Of course this condition is unattainable in practice. It is a mere expression of the direction in which it appeared desirable to advance; and, as I have already said, I am prepared to put it that the most perfect alternator conceivable is one which has an indefinitely small selfinduction and resistance. This idea that the generating or controlling power is connected directly with the self-induction is larly upset by the fact, shown by Prof. Ayrton's experiments,

[AUGUST 2, 1889.

that the self-induction is not sensibly altered by variations of the field strength or position. I need scarcely repeat that the generating or controlling power depends almost entirely on the field strength and position relatively to the armature.

But Mr. Swinburne sticks to the ordinary fallacy, and says-or implies that such a machine would not act at all either as generator or motor, and reproaches me for attacking existing theories without giving one of my own to take their place. Even that course would have been quite justifiable if I had found the existing theory bad. But I have given a theory. I have said what I thought a perfect generator or motor should be, and have attempted to explain the rationale of the action of two such machines when controlling each other. Let me take a case. The armature of my machine has a certain resistance and a certain self-induction. These qualities are unfortunately unavoidable, but I made the machine as good as I possibly could by reducing them both. This was done by the use of a strong and "stiff" field. Need I explain that, if the properties of iron had permitted it, I should have been able so to increase the field as to allow of a proportionate reduction of the resistance and of the self-induction of the armature? And if I could have got an indefinitely strong field I should have reduced the armature resistance and self-induction also indefinitely. Then I should have the "perfect alternators that I alluded to working as generators or as motors, singly or parallel.

"

But Mr. Swinburne, bearing out his opening statement, implies that such machines would not work at all.

Then, again, speaking generally, he says: "To make them run parallel commercially needs a large corrective tendency. This can only be got by making the machines so that the maximum current is not at the same time as the maximum E.M.F." This is exactly the opposite of the actually best conditions. Of course they need a large corrective tendency and great stability, as Dr. Fleming says. I urged this strongly in my paper (page 591). Inverting Mr. Swinburne's statement--which really means that the machines must have large self-induction-I say this large corrective tendency can only be got to its fullest extent by making the machines so that the maximum current is at the same time as the maximum E.M.F., at any rate when working on an inductionless circuit. Mr. Swinburne quite correctly interprets the restriction imposed by the conditions he thinks best when he says "that the machines must be made larger to give a given output. They must also be somewhat less efficient." The whole object of the first section of my paper was to show that such views were both practically and theoretically wrong, and I am surprised that a literal restatement of them should now be put forward. The best practicable alternator for any and every purpose should have the lowest practicable resistance and self-induction. It will not be larger for a given output or less efficient. It will not have its maximum current at a different time from its maximum E.M.F., and it will exert a large corrective tendency in the most powerful and unhesitating manner, and will maintain synchronism with the least difference of time-phase between any two machines. Such are the views to which I am driven by the logic of facts. On one point I agree with Mr. Swinburne-that if a large corrective margin is required, the internal loss must be large; but even here we do not fully agree. With the old theories the corrective margin was out of all proportion to the effect required to be produced. By the sudden and strong action I obtain by departing as far as possible from the old theories, I get this large corrective margin of power by a small margin in the capacity of the machine. It is obviously unwise, however, to attempt to run machines parallel when they require to exert s large controlling power. My experiments showed that they could exert this power; but the driving plant that requires large control is not suitable for parallel working.

Mr. Swinburne's calculations on the efficiency and dimensions of transformers are, I am sure, very interesting; but I scarcely think we are yet in a position to settle these matters entirely on paper. There are so many variables, and there is so little actual knowledge of the laws governing the heating by eddies and by hysteresis in transformers, that it is probably best to rely mainly on experiment for the present. Thus Prof. Ewing says (page 642) in his letter: "We cannot be sure that the loss by hysteresis is proportional to speed, especially when the speed is high;" and my experiments on armature cores support this view. Mr. Swinburne, however, is sufficiently sure on this and all the other points to rely upon his calculations for transformers working under widely different conditions. I admire his courage, but advise him to be prepared for disappointments when the transformers are constructed. I cannot at all agree, either, that the eddies in the iron are negligible, in spite of any calculations showing them to be inappreciable. It will be found that my tests bear out very closely the results as regards loss that are known to be obtained in low period direct current machines. Those experiments confirm, as regards hysteresis, the results of Ewing and Hopkinson; and as to the eddies, it is open to any one to check them by experiment or by reference to any reliable tests. I would, however, point out that in the celebrated paper of the Drs. Hopkinson on "Dynamoelectric Machinery" one of the two power readings which are available for this purpose is wrong, the total loss of power being given as less than the calculated hypothesis loss. I have pointed out this discrepancy to Dr. Hopkinson, and find that he of it. It was no doubt an incorrect reading. Prof. Silvanus Thompson and Prof. Forbes ask for information

* Phil. Trans., Part I., 1886.

aware

AUGUST 2, 1889.]

as to the governing of the engines driving the two alternators in the experiments. Those engines were not governed automatically at all; they were simply controlled by hand. Of course, if they had been well governed automatically, the tests would have been much less severe. As it was, it was left to the engine driver to give each engine as much steam as he thought was necessary. In such a case, if one engine is more powerful than another, the power of mutual control is severely tested; if the engines are working under similar conditions, then the corrective margin is not required to be large. The utmost strain is put on the arrangement when, as was done in the experiments, steam is entirely shut off one engine.

I trust Prof. Thompson will continue his very interesting experiments on the seat of the back E.M.F. in arcs. The subject requires investigation. The method used will probably yield useful results as regards a comparison between direct and alternate current arcs. There is one point to which I wish to draw Prof. Thompson's attention, and that is whether there is, in an A.C. arc, an effect of the opposing E.M.F. in producing a displacement of the current phase. I suppose it may be taken as proved that the arc has an E.M.F. as well as a resistance; and with a rapidly alternating current it seems possible that this may produce a lag, and may act in that respect something like electro-magnetic selfinduction. Such an effect may, perhaps, also be found in A.C. electrolysis. I note Prof. Thompson's criticism of my statement that in the characteristic the drop is partly due to resistance and partly to self-induction. He does not say that I am wrong. Several effects are produced by the currents-eddy and usefulgenerated by motion, and it is, I think, allowable to describe the net result on the characteristic as due to self-induction.

I have already referred to Prof. Thompson's expression of doubt as to whether there is time in a half period for the large mass of iron in the polar horns to become magnetised. He is probably quite right, but I have had no opportunity of settling the point. If there is any effect it will probably be almost a steady one, as pointed out by Sir William Thomson; that is to say, the iron will not follow the varying impressed magnetising force, but will take up an average state, depending upon the current and the relative position of armature and field.

Prof. Ayrton, in his opening words, appears to ally himself with the views that I have sought to upset; but I have to thank him for having contributed an account of experiments which, perhaps more than anything I can say, tend to support my contention. He referred to the method of testing transformers that I suggested. That method may be safely used, except with a very inefficient transformer.

As to the curves of temperature, I can only say that I have no reason to doubt the accuracy of the tests, which were most carefully carried out.

Prof. Forbes pointed out that it is wrong to suppose there are only two means of distributing alternate currents. I quite agree with him; but although I have dwelt at some length on the subject of working parallel, I do not think that method is suitable for all cases. It is a great convenience, and in a properly designed station can always be adopted; but where, either from the design of the machines or from the character of the engines, a large corrective margin is necessary, then it may be better to work singly, putting such of the mains in parallel on one machine as may be convenient.

If the alternators are suitable for parallel work, then the different mains may be run parallel from a common or omnibus pair of terminal bars, each main being fed through a safely fuse, in order to prevent more than local extinction in case of a short circuit.

With regard to Mr. Zipernowsky's communication, I am sorry he should think the statements I made about working his alternators parallel are erroneous. Those statements are substantially quotations from his own writings. He objects to a passage in my paper in which I said that his reason for working at the very low periodicity of 42 was to enable him to run the machines parallel. My authority was his own letter, published a few days before my paper. In this letter-to quote it more fully-he said: "The relatively low number of alternations (5,000 per minute), which we have chosen on principle that we by this means

are enabled to couple our dynamos in parallel is not a secondary result, but just the end we were aiming at." Mr. Zipernowsky now writes (page 672): "We state that we have not reduced the periodicity because of the coupling in parallel."

I must leave these two opposed statements to speak for themselves.

The other statement which Mr. Zipernowsky questions is that the magnetic flux in the field ought to be constant, and I am blamed for not giving my reasons for this statement. I did not go into the matter very fully, as it seemed unnecessary; but when I said that want of constancy "necessarily led to losses in the field, the lamination of which in the Zipernowsky machine showing that such losses must be serious" (page 629), I am sure I sufficiently indicated the nature of the waste which occurs under the conditions referred to.

I am glad to have clicited Mr. Zipernowsky's remarks about the Ganz alternate current motor, and shall look forward to seeing an actual description of that apparatus. The publications on that subject, to which my attention is called, are remarkable for the small amount of definite information they contain. I can learn nothing from them. We are not told anything at all about the

* The Electrician, May 10th, 1889.

135

form, mode of action, or principle of the machine. There are no doubt good and sufficient reasons for this reticence.

Of Mr. Fricker's contribution I need only say that it is a very clear statement, with which I wholly agree.

THE ELECTRIC LIGHTING SCHEMES.

Bills before the Commons Select Committee.

PROVISIONAL ORDERS CONFIRMED.

(Continued from page 111.)

On Thursday, as soon as the Committee were ready to com

mence,

Mr. MOULTON expressed a desire, as the Committee were that day going to hear the opposition of the gas companies, to direct attention to the clauses in the Provisional Order granted to his company-the London Electric Supply Corporation.

Mr. POPE: I object to this. He is not entitled to make a speech in favour of the Bill which is submitted to you.

Mr. MOULTON: I desire to point out to the Committee the origin of the works' clauses in the provisional order.

The CHAIRMAN: I think we had better pursue the course we pursued yesterday, and allow the connsel who has charge of the clauses to begin. Will you refer me to the clauses in the order to which you refer ?

Mr. MOULTON: They are 16, 17 and 76 (as to altering pipes, wires, &c., under streets; the laying of electric lines, &c., near those of gas or water companies, and near sewers, drains, &c. ; and for the undertakers to be responsible for damages).

course,

Mr. POPE (who, with Mr. Bidder and Mr. Danckwerts, appeared for the Gas Light and Coke Company), in bringing up the clauses which he said ought to be put in all the provisional orders for the protection of the gas companies, stated that the discussion, in all probability, would to-day practically settle a series of model orders which would be adopted in the provisional orders as affecting all the gas companies. The Gas Light and Coke Company was, of the largest corporation undertaking the supply of gas in the metropolis, and it so happened that by a series of amalgamations sanctioned by Parliament that company had the supply of gas covering the whole of the area affected by the provisional orders, and that was why the company attended there by counsel to discuss the question in their individual interest, although practically they were representing the interests of the gas companies generally. Had there been any pressure put upon him he should have declined, as representing the gas company, to bring forward clauses for the mere purpose of obstructing an enterprise which might be a competitor with the gas companies. But they had not put any such pressure upon him, for the gas companies were perfectly prepared to accept the competition which Parliament was about to sanction between the electric light and the gas, and all they desired was that the protection they were entitled to for their property and undertakings should be fair and reasonable, and that in the desire to encourage a new enterprise or undertaking, no wrong or injury should be done to those who were already in possession of the field. The position of the gas companies as to their rights regarding the works which they had executed was now pretty well settled in point of law. There were doubts entertained as to the rights of the gas companies in the pipes which they laid, and in the works which they executed for the supply of gas. There could be no question, however, that the state of the law was this-that the gas companies were there by statutory title, and had laid pipes in the public streets, and were entitled to precisely the same protection which any other owner of property was entitled to in regard to the safety and maintenance of property which belonged to them. They were entitled to this amount of protection-with regard to any Act which might injure their undertaking, and in respect of which they would be entitled to bring an action for damages, if that act was not done under the protection of Parliament. If damage were done to the main pipes or the gas supply of the company, they were entitled to have power to bring an action. Proper protection should be given to the company in respect of any right which was taken away from them. The law was that they were absolutely entitled to noninterference, and that if any damage arose from any act which was not jusiified by Act of Parliament, they were entitled to take action for damages, and to obtain a remedy. The provisional order operating as an Act of Parliament would enable the electric lighting company to do that which without an Act they could not do, except under a liability of compensation to the gas companies. He did not mean compensation in respect of competition, but in regard to any injury done. There were two important points which ought to be provided against. The first was as to danger. They ought not to be subjected to increased danger in the carrying out of their gas supply by reason of the powers which might be given to the electric lighting companies. Secondly, they ought to be allowed a protection wherein the laying of the mains and the construction of the works the electric lighting company should not, as it were, spread a net over the streets of the metropolis which would make it difficult or impede the gas company carrying on their own works for any purposes whatever, Those were the two

points to which the clauses were directed. The essential part of the clauses were not repugnant. Undoubtedly as long ago as last March clauses were agreed to between them and the Metropolitan Company, and there were clauses which for several years had, without exception, been given the Gas Light and Coke Company and other companies by every railway company which had interfered or proposed to interfere with their works or mains, and they had in fact inserted those clauses for several years past in all the railway bills. Mr. Pope then proceeded to read the clauses as follows:

By way of addition to, and not in derogation of, the provisions of the principal Act and of this order, and for the protection of the Gas Light and Coke Company (in this section referred to as 'the Gas Company'), the following provisions shall have effect (that is to say) ::

"A. Whereas in the execution of the works (other than the alteration of the position of any pipe) by this order authorised, the mains, pipes, syphons and other works belonging to the gas company may be intersected or otherwise interfered with, and it is expedient that the gas company should have full control over the execution of all works in any way affecting the supply by them of gas, so as effectually to provide against the supply thereof being impeded, be it therefore enacted that all works, matters, or things (other than the alteration of the position of any pipe), which, under the provisions of the principal Act, or this order, the undertakers may be empowered or required to do or execute with reference to or within 5 feet of any of the mains, pipes, syphons or other works of the gas company, or which under the provisions of the principal act or this order are empowered or required to be done or executed by the undertakers, and may or does interfere with or prejudice the alteration, repair, user, or enjoyment of the mains, pipes, syphons, or other works of the gas company or supply of gas therefrom, shall be done and executed by and at the cost of the undertakers, but to the satisfaction and under the direction of and in such manner as shall be required by the engineer for the time being of the gas company; and such works, matters, or other things shall not be commenced until after 14 days' previous notice thereof in writing shall have been given to the gas company; and the undertakers shall not lay down any such mains, pipes, syphons, or other works so as to interfere with the observance of the regulations or directions of any Act of Parliament relating to the gas company. Provided always, that if the gas company shall elect themselves to execute any portion of the works, matters, and things which the undertakers may by this order be empowered or required to do or exercise with reference to or affecting the mains, pipes, syphons, apparatus, or other works of the gas company, and of such their election shall give seven days' notice in writing to the undertakers by leaving the same at their head office, the gas company may themselves execute that portion of the said works, matters, and things; and the reasonable expense of and incident to the executing the same shall be repaid by the undertakers to the gas company. Provided also that in cases of sudden emergency arising from defects in any of the pipes or other works of the undertakers which may require to be remedied without delay, the notice to be given as aforesaid shall be given at the earliest possible time, and not later in any case than immediately upon the commencement of the work. In default of any such notice as by this clause required being given, the undertakers shall (without prejudice to any other remedy of the gas company) forfeit or pay to the gas company a penalty not exceeding £20, and any expenses the gas company may incur through the absence of such notice.

"B. If any interruption whatsoever in the supply of gas by the gas company, or any loss or escape of gas shall be in any way occasioned or sustained by any act or omission of the undertakers, or by the acts of any of their contractors, agents, workmen, or servants, or any persons in the employ of them, or any or either of them, the undertakers shall indemnify the gas company against all penalties and costs to which the gas company shall become liable in consequence thereof, and in addition shall pay to the gas company the value of the gas so lost. If the undertakers shall find it necessary to undermine but not otherwise alter the position of any main, pipe, syphon, or other works belonging to the gas company, they shall temporarily support the same in its position during the execution of their works and on their completion shall provide a good and suitable foundation for every main, pipe, syphon, or other work so undermined.

:

"C. Nothing in this order shall authorise the undertakers to employ any of the works, mains, or pipes of the gas company, or any works, culverts, mains, or pipes in connection with those of the gas company, as supports for any works of the undertakers, or as conductors for the purpose of completing the electric circuit and the undertakers are hereby prohibited from so employing any of such works, culverts, mains, or pipes, or from in any way bringing their electric mains, wire, or services into contact with or nearer to such gas works, mains, or pipes than shall be agreed upon between the engineer for the time being of the undertakers and the engineer for the time being of the gas company.

"D. Wherever an electric line, wire, tube, main, or other apparatus for the supply of electricity shall cross or be liable to touch gas mains, pipes or services, it shall be thoroughly encased on insulating covering to the satisfaction of the engineer of the mpany for the time being.

The expense of all repairs or renewals of the said pipes or or any works in connection therewith, which may at any eafter be rendered necessary by the acts or defaults of the ers, fr contractors, agents, workmen, or servants, or

[AUGUST 2, 1889.

any person in their employ, shall be borne and paid by the undertakers.

"F. Nothwithstanding anything in this order contained, the undertakers shall be responsible for and make good to the gas company all costs, losses, damages and expenses which may be occasioned to the gas company, or to any of their mains, pipes, syphons, apparatus, property, works, and conveniences, or of any loss of gas or interruption in the supply of gas by the gas com pany, or otherwise, including injury and loss by explosion through, by reason of, or consequent on the execution or failure of any of the intended electric works and apparatus, or of any act or omission of the undertakers, or of any of their contractors, agents, workmen, or servants, or any of the persons in their employ or in the employ of their contractors or others, and the undertakers shall effectually indemnify and hold harmless the gas company from all claims and demands upon or against them by reason of such execution or failure, or of any such act or omission.

"G. Except in cases of sudden emergency arising from any defects in any of their mains, pipes, or other works which may require to be remedied without delay, the gas company shall not execute any work so far as it immediately affects the supply of electricity except under the superintendence of the undertakers, unless they refuse or neglect to give such superintendence at the time specified in the notice for the commencement of the work, or discontinue the same during the progress of the work; and the gas company shall execute such work at their own expense and to the reasonable satisfaction of the undertakers. Provided that any additional expense imposed upon them by reason of the existence of an electric line, wire, tube, main or other apparatus for the supply of electricity in any road or place where any mains, pipes, syphons, and other works belonging to the gas company shall have been laid before the passing of this order, shall be borne by the undertakers.

"H. Nothing in this order shall take away or abridge any power to open or break up any road along or across which any electric line, wire, tube, main, or other apparatus for the supply of elec tricity is laid, or any other power vested in the gas company, for the purpose of laying down, repairing, altering, or removing any pipe for the supply of gas or other work, but in the exercise of such power the gas company shall be subject to the following restriction (that is to say)

"1. They shall cause as little damage or inconvenience to the undertakers as circumstances admit of.

"2. Before they commence any work whereby the supply of electricity will be interrupted they shall (except in cases of urgency arising from defects in any of their mains, pipes, or works, in which cases no notice shall be necessary) give to the under. takers notice of their intention to commence such work, specifying the time at which they will begin to do so. Such notice to be given 48 hours at least before the commencement of the work.

"3. Any difference arising between the undertakers and the gas company respecting any of the matters referred to in this clause shall be determined by arbitration.

"I. Except as is by this order expressly provided, this order, or anything herein contained, shall not take away, diminish, alter or prejudice any of the rights, powers, privileges, or authorities of the gas company.

"J. Any difference (not being a question relating to a penalty recoverable summarily, or to an injunction or mandamus) which may arise between the gas company and the undertakers under or out of the provisions of the principal Act or this order shall, at the request of either party, be determined by arbitration. The award made upon any such arbitration may be enforced as though the same were a judgment or order of the Queen's Bench Division of Her Majesty's High Court of Justice. The Board of Trade, if it thinks fit, may at the request of either party appoint a legal arbitrator or a legal assessor to the lay arbitrator appointed by the Board. The remuneration of any arbitrator or assessor appointed by the Board shall be fixed by the Board, and shall form part of the costs of the reference."

Evidence was then given in support of the petition which had been read, and the first witness was

Mr. J. Ó. PHILLIPS, who (examined by Mr. BIDDER, Q.C.) said he was the secretary and general manager of the Gas Light and Coke Company, and had had 27 years' experience of the gas supply of the metropolis. Their district was the result of the amalga mation of many companies and embraced nearly the whole of the north of London, and a part of it south of the Thames. The total capital of the company was about £12,000,000, and the total annual sale of the gas was 19,000,000,000 cubic feet, representing

1,750,000 tons of coal.

Mr. BIDDER: You have mains, I suppose we might say, in almost every street in your district ?-In every street, lane, court, and alley in the whole of the district.

And you light something like 55,000 street lamps ?—Yes.
And you supply 206,000 private consumers at the present time?

-Yes.

And you pay £150,000 a year in parochial rates?-Last year we paid for parish rates £160,000.

That is sufficient to enable the committee to understand the magnitude of the interests represented by the company. Your principal works now are down at Beckton ?-Yes, below Woolwich, on the north bank of the Thames.

Besides those you have subsidiary works in different parts of London ?-Ten of them.

I may take it that the whole of the districts which are the subjects of the provisional order before this committee are within your district of gas supply?—I think every one of them.