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of an apparatus similar to the bell punch used in checking the receipts of tramway conductors.
Having introduced the electric mains into the houses of the consumers, the duties of the undertakers end as far as they can be discussed in this paper. Several important points, as regards the time and duration of the supply, require to be arranged, also the question of the charge which the undertakers shall be entitled to make to the consumer for the energy supplied.
In the foregoing remarks the incandescent system is supposed to have been adopted throughout. Should it be determined to light the streets, squares, and public buildings, the arc system would be far the most economical, although it is very questionable as to whether for street lighting, gas is not still the best illuminant. It would be, in any case, advisable to lay a separate main for furnishing the electric current to the street lights and other public lamps which would require to be lighted and extinguished at a fixed time throughout the year.
The saving of the wages of the traditional lamp-lighter would be one economical step towards bringing the price of electricity to that of its cheapened rival,-gas.
Mr. Thos. H. BLAKESLEY: Mr. President and Gentlemen,-It is only by your courtesy that I am present at this meeting, being unfortunately hitherto a stranger to this Association. I have therefore to ask your indulgence, in venturing to address to you a few remarks upon the important questions touched upon in Mr. Hedges' interesting paper. It is a very important thing that the local authorities generally should be thoroughly well informed of the action of the Legislature which has taken place recently. I suppose most of those present have had their attention called to this subject. It has been my duty to examine minutely the Provisional Orders sought by the companies in the matter of electric supply, and therefore, as I have had to study the details, perhaps what I have to say may be of interest to the Members of this Association. The Act of Parliament on which all future electric lighting on a general system is to depend, is in many respects very disappointing, but the action of the Board of Trade, in whose hands the bill became law, and who have been invested by it with so many functions and duties, has been in the discharge of those functions and duties, for the protection of the public, more disappointing still. We have now only the local authorities to stand between us and the operations of the Electric Lighting Companies, and thus it will be to the Members of the Association of Municipal Engineers that we must ultimately trust. Do not imagine that, in making these remarks, I am in any degree opposed to the general introduction of electricity. It is because I know so well how useful an agent it is, that I am unwilling it should be monopolised, as gas and water have too frequently been, in hands which are certainly not the best. You hear of large public meetings called together to promote the merging of metropolitan affairs in one central authority, while the Board of Trade is busy granting the most extravagant demands of electric companies. I have called the Act disappointing, and I think it will be considered so by those who appreciate all the uses of electricity. It will hardly be believed that out of 3163 questions put to witnesses before the Parliamentary Committee on Electric Lighting, there was no single question upon the subject of alternating currents, their applicability, efficiency, and danger. Compared to direct currents they are dangerous to life, inefficient in action, and limited in applicability, being useless for storage batteries, and comparatively so for conversion into mechanical energy. Yet the companies are to be allowed to supply alternating currents, and so put a serious limit to the applications of electricity. As regards public purposes, the Act in so many words limits the application to lighting. A church, or other public building, may be lighted but must not be ventilated by electricity, and streets may be lighted but not swept by it.
For private purposes it is true there are no such direct limitations; but the companies have found means to provide them indirectly. Now, why should they exist ? The explanation is, that the companies dread having their power of supply over-taxed, but still wish to skim the cream from a very large area. You must remember that directly we have a proper supply of electricity, mechanical applications of it will swarm. But the companies deny that they seek a monopoly, and assert that other undertakers are free to supply, if they can obtain the powers to do so. I will show
will allow me, one reason why, if this were to take place, it would be to the disadvantage of the public. It is a law of economy in the designing of a conductor, that the sectional area to carry a given current varies as the square root of the hours per day during which the current flows. Now suppose a company, A, supplies a certain current for the twelve hours of night for lighting purposes. The economical section of its conductor is then fixed by this law. Suppose it is S. Now another company, B, comes and supplies the same current for mechanical purposes during the twelve daylight hours. B must put down another conductor, also of section S, and the public has to pay for the double section 2 S. But if one company were to supply the current for the whole twenty-four hours, the section of the one conductor necessary would not be 28, but ✓ 2 S, or 1.414 S. This would be a saving of 6 in 20, or 30 per cent. on expense of main, besides there being only one system to interfere with the streets. This is a simple case. but one of a general rule, admitting of mathematical demonstration, that economy from a public point of view depends upon the supply of electricity for all purposes being in the same hands; and those hands, in my opinion, should be those of the local authorities. The author of the paper has alluded very significantly to the dangers to the insulation arising from a damp situation. Some striking illustrations of this have taken place in the mine of La Peronière in France, where there is a case of electric transmission of energy for 1200 meters from the pit's mouth, for winding coal tubs. Of course there were many damp situations in this mine, and in them the original insulation did not hold longer than about one month, though it was composed of indiarubber and Chatterton compound. A lead coating, such as has been suggested by Mr. Hedges in his paper, was tried, but did not answer any better. Only after guttapercha was employed was the insulation maintained; and it really seems as if this were the only flexible conductor which will permanently resist the action of damp. I have thought that, on this account, it may be necessary in a town system to fill the pipes or other chambers containing the mains periodically with air, dried artificially over sulphuric acid. The volume required would not be unmanageably large. Returning to legislation, when we come to modes of supply, it is to be observed that the parallel system and series system are both sanctioned, but all regulations as to price and measurement refer to the parallel system, so that the undertakers can escape them by adopting a form of series, e. g. putting every two houses in series with one another. The standard pressure on which the charge to a consumer is based is the electro-motive force, between the junctions of his service lines with the distributing mains. Obviously there can be no standard pressure if the house
holder has only one service line making junction with the distributing mains. Then there is the question of electric pressure. The lower limit, 30 volts, is quite inadequate for the best and most economical lamps, corresponding in brightness to an ordinary gas jet. The undertakers may make the services of such a resistance as to absorb 21 per cent. of the energy supplied at the junctions of the mains and series. This is simply for the purpose of selling the energy so absorbed, as it is not really necessary to absorb in the services anything like this amount. I have supposed a case of a house having 30 Edison lamps of about 15 candles each, and have calculated the length of service lines that by this rule, and that relating to safety in services must be employed. It is 100 yards altogether, i. e. 50 yards for each service line, and this with No. 8 Birmingham wire gauge, which would be the smallest allowed under the circumstances. This is clearly far more than the distance from an ordinary house to the kerb. Then I come to the modes of estimating the energy to be charged for; and draw your attention to the third mode under which the undertakers may assume that the whole maximum supply has been taken during the whole time that any has been taken at all. When a man burns only one lamp
be assumed that during that time he has been drawing his full current. Can anything be more unjust ? Professor Fleeming Jenkin described this clause, in his report, as being so monstrous that he imagined some other meaning must be intended than the straightforward one, but he had been unable to discover any other. Of course he could not, for no other was meant. Yet the Board of Trade have introduced this clause unaltered into the Orders. I think I have now said enough to show that local authorities ought to be most careful, even in dealing with the Board of Trade; and I beg to thank you, gentlemen, for the patience with which you have heard me.
Mr. BURSTAL: It seems to me there is a consensus of opinion among the gentlemen who have addressed us. According to their idea, gas and water works are monopolies, unnecessary things. Now I wish to say the gas and water works in this country have been mainly established by companies and not by corporations. Where they have been undertaken by corporations, they have generally been taken over from private companies in a high state of efficiency
-taken over for the benefit of the ratepayers, but not established by the ratepayers or their representatives, who had not the necessary commercial enterprise. I stand up for the gas and water
companies, because they have done a great deal for this kingdom; I can say they have done a great deal more at present than electric lighting companies, if we may judge by the Brush shares, which have been nothing at all but a commercial speculation. We have seen them, sir, quoted from 50 to 83. I do not wish to oppose electricity, but I wish to stand up for gas and water companies, which I think have done their duty. I can say, from the undertakings which I have been connected with in the midland counties -and I see a gentleman present who presides over one of the largest—that they are most efficient, and I do not think that they should be subjected to such attacks. It was said " there are many objections to granting companies free control of the streets.” So there are, but how are you to get over it? You must give somebody control, and I don't think it matters much whether you give a person in the employ of the gas company the control. They both dig a hole, and they repair the road again much in the same way. On page 2 Mr. Hedges says, “In the case of a town having sufficient water power available dynamo machines to utilise this force would be erected with suitable motors as near as convenient to the source of power.” There may be a few towns in England, and they would be chiefly in the lake district-Cockermouth I have in my mind—with sufficient water power to drive dynamo machines; but there are very few other towns with the requisite power in summer and winter, without constructing large storage reservoirs, and therefore I think the subject of driving dynamo machines by water power in England may be dismissed. In London the engines, boilers, dynamo machines, are to be underground in squares, with only the chimney visible. That would be very pleasant indeed in the centre of Russell Square, and I have no doubt the Duke of Bedford would have something to say about it. I think something more practicable must be suggested before a meeting of engineers can say that the supply of electricity is altogether practicable. I quite agree with what Mr. Blakesley has said respecting one company having the supply of electricity both for lighting and motive power. Of course there should only be one, but the work of one company would be more than double what it would be for the two companies. If one company supplied light from 6 A.m. to 6 P.m., and the other power from 6 A.m. to 6 P.M., of course there would be some people who would want to use power after 6 P.m., and there would be lighting in addition. Therefore, in the winter time especially, the work of one company would be