THE

HMLECTRICALIL REVIHW.

AUGUST 9, 1918,

No. 2,124

Vou. LXXXIII.

ELECTRICAL REVIEW.

Vol. LXXXIII.) CONTENTS: August 9, 1918, (No, 2,124,

Page Efficient Publicity Work ... soe eee ~_ wes eco. 191 * All's Well that Ends Well” 122 Economic Policy ... , 123 Patents and Enemies oes _ one —_ owe ~-— An Electrieally-Welded Ship (illus.) ... eve eee oe «300 The Future of Coal Using, by W. H. Booth ... eee we 125 Mining Electrical Engineering, by C. Jones (illus.) ... we whet Relay Automatic Telephones at Australia House (illus.) 127 Legal eee coe ooo ose ost a _ ua I War Items ... eee eve ove ove oes on oo. Correspondence— The Nottingham Super-Power Station ... eee soo «180 Instruments for Central Station Switchboards ... a Trade Unions: Past, Present and Future ... ane —_. ae Motor Problems _ eee eee eee a oe Business Notes eve ov eco ove eee eve oe Fea Notes eee eee eee woe eco eco eee coe §6=2185 C.ty Notes ... eee one eee ove eee ove ne Stocks and Shares ... ose eee eco eco oe oe 166 Exports and Imports of Electrical Goods during April, May, and June, 1918 ... _ eco ° coe ao

The Education and Training of Engineering Apprentices, by P. H. 8. Kempton (concluded) ... on se ons a See

Tar Oil as a Motor Fuel (il/us.) ... ham = wt wa 2 Trade Statistics of India ... a“ see aes bias we. Foreign and Colonial Tariffs on Electrical Goods iad coe ©6144

New Patents Applied for, 1918 ... ove ove eee cco «(346 Abstracts of Published Specifications ... eco eee ooo 244 Contractors’ Column on an --- Advertisement page xxii

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EFFICIENT PUBLICITY WORK.

DURING the progress of the war, journals which represent industries that are of direct importance in connection with the production of war requirements are, for various reasons, debarred from particularising achievements which, under normal conditions, it would be to the advantage of those engaged in such industries to be acquainted with. Such journals have had added to their accustomed responsibilities certain very essential functions, which they perform in the interests of the Allied

cause and in the interests of

their industries, and their usefulness is recognised in Government quarters as was never the case before the war ; but, for obvious reasons, there are accumulating to be described and discussed, in times of greater freedom, when initiative may be exercised under less restraint, what are really arrears of very useful matter. It has been one of the responsibilities of editorial life during the war to practise a ceaseless vigilance in order to prevent the appearance of

To the

enterprising newspaper alwayson the look-out for really useful

matter which could be of assistance to the enemy.

matter, it is naturally a great disappointment to have to refrain from publishing such material when it has been offered. In most cases, however, we believe that the duty has been faithfully and loyally carried out—though not by any means always—because of the earnest desire of the Press to hasten the defeat of the enemy.

The present handicap, however, will come to an end sooner or later, and it appears to us important that if there is any weakness anywhere which will prevent the publication in the technical Press of the facts concerning the abilities and achievements of British electrical and engineering manufacturers, steps should be taken to remove it. now. Both during the war and for several years preceding it, we frequently drew manufacturers’ attention to their own unfavourable position in comparison with German com- petitors in this matter. The British method often seemed to be to hide the manufacturers’ light under a bushel by adopting a definite policy of secrecy concerning their opera- tions, so that their home competitors should not know what they were doing, or else there was an apathy concerning publicity which let sach matters drift.” a

There were some brilliant exceptions—but they were rare, and we could count them upon our fingers. We remember other cases where information was flatly refused to the Press for fear anything should be given away ; where we were definitely asked to certain items ; where there was no time to spare to collect data ; or where there was a disposition to help, but no efficient assistance available for securing essential material from a firm’s own documents. We believe that the war has brought a new atmospherd and a greater desire for efficiency which will obviate some of these difficulties in future ; but what will help the situation more than anything else is the adoption of a fully enlightened policy on the part of the individual manufacturer under which he will co-operate

sup} ress

[121]

122 THE ELECTRICAL REVIEW. [vol. 83. No. 2.124. Aveusr 9, 1918.

with the Press through his own efficient representatives. We use the plural intentionally, because it is not upon what we have come to regard as the publicity man” that the responsibility for shortcomings has always rested. Some of these representatives have. been, in our estimation, “poor things,” it is true—quite incapable of efficiently carrying out their duties in co-operation with the Press ; others have been first-class men, but—lIsraelites in Egyptian bondage - they were unable to make bricks without straw, because those to whom they ought rightly to have been able to look for sections of the material necessary for making the complete record, were not possessed by the same appreciation of the importance of publicity as, or were less energetic than, the * publicity man.”

The subject is of some considerable importance in con- nection with our aft€j-the-war industrial activities. There is no doubt whatever that German propaganda methods will have to be very carefully watched by the Press. We know something concerning their methods of the past—good and bad ; the. former contain points which British manu- facturers would do well to copy, for there was no indis- position in Berlin and elsewhere to furnish through a well- organised literary and photographic department, or through recognised literary correspondents, descriptive accounts of inventions and installations which, because of their technical and industrial value, were of interest to British readers. Of their future methods we cannot gather as much information as we should desire all at once, but we have learned some of the possibilities, and to these we may refer later. But while we shall require to exercise great care, in order that their ends may not be unconsciously served, there is, as we say, one thing that is immediately possible, and that is, that individual manufacturers adopt a large-minded policy, and improve their own facilities.for meeting the requirements.

Speaking broadly, it must be stated frankly that for many years past the possibilities of commercial publicity propaganda, as a means of securing a firm hold on the markets of the world, though frequently urged upon the mind of the British manufacturer and engineer, have been followed up too apathetically, and, in consequence, with disappointing results on the whole.

The attitude of mind which has resulted in this apparent indifference, and even hostility, jo methods which are logically in keeping with the general growth in knowledge and education the world over, may have an easy ex- planation from the British standpoint. We cradled the world’s industries in the past ; we built for the world and instructed it ; we occupied a position of splendid industria! isolation, and the world came to us; but nowadays the foster parent is surrounded by a numerous thriving progeny —self-reliant peoples to whom British prestige is a memory rather than a reality—and this, we are afraid, many of our manufacturers and engineers are only just beginning to realise. ~ Brown and Smith,” who 60 years ago were as well known in Australia as they were in Sheffield for the excellence of their, gsteelware, seem still to be under the impression that because they are even better known in Sheffield to-day, therefore their reputation in Australia and elsewhere is similarly enhanced.

The utter fallacy of this short-sighted attitude—based on the supposition that “because you know, everybody else knows ’’—is only too evident. —e

The Australians went to Brown and Smith 60 years ago because there was no one else to go to, and, no doubt. they got good value for their money, and the firm established a corresponding reputation ; but the Australian of 60 years ago is no more, and the * reputation” is in process of being snowed under by the insistent claims and pushfuil methods of more energetic present-day rivals.

Anyway, a reputation needs careful nursing, or its owner is like to find it wearing away in course of time. and this is precisely what is happening to many British reputations— heirlooms of a. bygone generation, valued only by the owner and forgotten by the world. Government trade de- partments have scen this during the war, and as a result have advised our manufacturers, at all costs, to keep repre- sentatives at work in the different markets so as their firm’s memory green.

to keep

Publicity propaganda is the simple and obvious method, and in many cases the only method, of telling the younge1 generation what you have done, are doing, and are going to do; in no other way can the modern business world be reached. To the engineer particularly it should appeal, as his products are too bulky and too costly to carry round in the traditional carpet bag.

We believe that in many cases where there is a tendency among the engineering fraternity to disparage publicity work of the best kind, this is, as suggested above, due to the short- sighted views held by the works staffs, on whom the publicity men are generally dependent for information. It is to be feared that some of these gentlemen suffer, perhaps uncon- sciously, from distorted vision ; it may be that like a certain famous Admiral they apply their telescope to a blind eye when they view the world—a comparatively small place, by-the-bye, which surrounds the works—and it is quite certain that they do not realise that they may turn out the finest product on earth and yet’ eke out a bare existence, because they are comparatively unknown.

In any case, it is up to the works to back up the efforts of their own publicity branch, if they have one, in every possible way, and thereby stimulate the selling of their pro- duct, to which their own cussedness is perhaps the only obstacle.

Needless to say, we have the greatest respect for the technical work of our engineer designers and constructors, and their environment affords some excuse for a limited view of life, but that they are hopelessly wrong in adopting this attitude goes without saying.

It would probably be of immense value if our construc- tional staffs could be better informed on the selling side of their business—the salesman has hold of the right end of the telescope, and is usually under no misapprehension as to the necessity of spreading the fame of his firm in every available market and by every available means ; but, so far as publicity is concerned, he finds shoal water—if not a sunken reef—when he approaches the works, and it is a very much overdue and frequently unrecognisable craft which gets clear—if, indeed, it ever does get clear !

We do not wish to inquire who is to blame, so much as to suggest to those whose duty it is to set the matter right that they should urge their staffs to show a befitting spirit of publicity enterprise.

SHorTLy after the outbreak of war, a

“All's Well that sip: Pee Ends Well,” c¢Ttain organisation for which we have great respect, but which shall be nameless, issued circular letters to its members on a matter of interest respecting its membership. As a result of exchange of cour- tesies, there were indications of repentance at leisure. Much had to be excused in those days, for everybody was more or less under the influence of excitement, and it fell to our lot to persuade our readers to stay their hand and not to be precipitate in posting suggestive or angry letters, even if they must wvife them. To-day, when we are all four years older, and when the times are quite serious enough from every point of view, there may be war-weariness in some quarters—it may even affect some who are either con- nected with, or somehow or other dependent upon, the elec- trical industry—but there is no excuse for hurried communi- cations now. Yet when they have been issued without full consideration, it is quite fitting that history should repeat itself. and that repentance at leisure should follow the issuance of some humorous and, therefore, easily mis- understood, some crude and, therefore, ill-thought-out, Notes on Advertising.” The circulation of the following explanatory or corrective missive spares us the necessity for dealing with this matter in detail, as we suggested we might require to do. It has been sent to many of our friends in the industry, and while it is not always easy to get on the heels of. a terminological imexactitude, we are content to say that All’s Well that Ends Well.” We cannot very well describe the original circular as a * Midsummer Night’s Dream”: we should be inclined to

)

regard it as an April Nightmare. It certainly is Love's

Labou f wh Associ really

At Advert and th which Public

At Associ Journ etter count: ietter

suppl !

Th f N respe of Bn catio whic

enter

ne

Vol. 83. No. 2,124, Aveust 9, 1918.) THE ELECTRICAL REVIEW. 123

Labour Lost.” In any case, it was a * Comedy of Errors f which we cannot for a moment believe the important Associations saddled with the responsibility for it wer eally the originators.

COPY.

NOTES ON ADVERTISING.

Memorandum of Conference held on July 9th, 1918

At the end of April a circular-letter. headed “Notes on Advertising,” was circulated by the British Engineers Association and the British Electrical and Allied Manufacturers’ Association which Associations are amongst the founders of the Industria Publicity Service, Ltd.

\t a conference on July 9th between representatives of thess Associations and the British Association of Trade and Technical Journals, Ltd., it was pointed out that certain statements in this etter were considered to be prejudicial to the trade Press of this ountry. As this was contrary to the intention of the circular- etter in question, it was agreed to make the following joint supplementary announcement

1. That although the paper situation is serious, there is no intention to publish trade journals fortnightly instead of weekly.

2, That the cost of printing has now increased by 75 per cent.. and the priceof paper by 600 per cent. or 700 per cent.. and the increase to the cost of production fully justified the proprietors raising the advertisement rates or reducing the size of space.

The trade Press of this country is acknowledged by the Ministry

National Service to be of National importance, and in this respect is classified with the daily newspapers. It is in the interest of British manufacturers that trade journals maintain their publi cations at their present high level, in view of the important part which they must necessarily take in the renewal of commercial enterprise and reconstruction at the close of the war.

Ir is satisfactory that British manu- facturers have received from the lips of the Prime Minister and of Mr. Bonar

Economic Policy.

aw a more detailed declaration than has hitherto been found possible concerning our economic policy. Anxieties regarding affairs in France have so engrossed the attention of the Ministry since March last that it is only now, when the outlook has improved owing to the carrying of certain legislative measures and the fuller intervention of American forces, that ideas have been able to take anything approach- ing definite shape. The policy of Preference within the Empire has been adopted, as already stated; but beyond that, little that is yeally definite can be said,.because the actual decision must be arrived at in consultation with the United States of America, as well as with the British Dominions. Mr. Lloyd George and the Chancellor of the Exchequer have, however, said enough to show that so far as they are concerned the industries of the British Empire will be protected against the future assaults of the enemy. The Prime Minister is very emphatic in the de- claration that the industries essential from the point of view of national defence and security must never again be allowed to be weakened. Mr. Asquith, Sir A. Stanley, Mr. Runciman, and others who have filled profninent Ministerial posts during the war have said the same thing again and again—indeed, we think there could hardly be a dissentient voice from any true loyalist on such a point as that. The present interference with trade, imposed under the extreme necessities of unparalleled conditions, must not be continued any longer than is absolutely essential to efficient return to industrial order, but Mr. Lloyd George adopts the view of Dr. Addison and other advisers that there must be a measure of control until the transition period is passed. We believe that manufacturers in their hearts recognise that necessity when they urge in the .interests of real industrial progress and security the removal of the irksome restraints and _ interferences which have irritated and handicapped them for so long. Capital and Labour are both agitating for their freedom ; both object to too much control. The former expresses itself in orderly fashion, while the latter breaks out occasionally with strikes against limitations’ of its liberties and against embargoes. We all want to get back to normal freedom of operations just as soon as ever it can be arranged—it is the independence that is in the very

blood of the British Democracy that thus expresses itself. Mr. Lloyd George’s hope that the Mother Country and the whole Empire will remain with the Allies in an indissoluble partnership after the war is shared by all who have th interest of world freedom at heart, and we believe it to be inevitable that an economic policy shall be developed between all which will enable us to share in Peace the bene- fits of common understanding. But the predominant-intlu- ence on the situation is the fact that America is completels with us in the war, and we have so to frame our economic policy in conjunction with her that harmonious relations shall be perpetuated. Mr. Lloyd George is ** very hope ful” that when America is ready to express herself there will be found to exist a ground for complete agreement between us. Taken in conjunction with these sentiments, we find Mr. Bonar Law’s declaration and observations equally accept- able as part of a whole policy— presumably developed as far as it is possible to develop it at this juncture, as one of the matters which must inevitably come before the electorat in the course of a few months, when we have to elect a new House of Commons and new Ministers to decide the terms of Peace and to carry us, we trust, through the first few years of reconstruction.

> . In our issue of July 12th we stated that atents an

the Government were seriously considering Enemies. :

the question whether the payment of fees for the maintenance of enemy patents in this country and British patents in enemy countries should be allowed to continue ; on July 19th we recorded the fact that the Board of Trade, no doubt instructed by the Cabinet, had summarily prohibited such payments. It was an accomplished fact, and nothing could be done but accept the decree as such, sut was it a wise step? We wonder whether the Govern- ment secured the advice of competent men before making this unexpected and drastic change in procedure, which may have far-reaching and highly disagreeable consequences.

According to a statement made in the House of Lords, the revocation of the licence relating to the payments to, and on behalf of, enemies, will not have the effect of annulling the 944 enemy applications for patents which have been filed and accepted since the outbreak of war. No other country except, perhaps, Russia, has cancelled such appli- cations. All of them are, or will be, vested in the Public Trustee, who can grant licences to British subjects, if required ; their future treatment depends upon the terms of peace.

Lord Somerleyton, speaking for the Board of Trade, said that the withdrawal of protection from inventions in such cases would mean a scramble by each country for the inven- tions of the other; Lord Armaghdale,° who raised the question, held that the object of these patents was to impede British industry. Both seem to have overlooked the fact that the prime purpose of granting Letters Patent is not to create a monopoly for the inventor, but to secure to the public the benefit of inventions. An invention that is not patented may prove as useless to the public as to the inventor, for manufacturers will not put down costly plant to exploit an unprotected invention. It is desirable, therefore, that inventors, whether British or foreign, should be encouraged to apply for Letters Patent, in order that licensees may have protection for their outlay. If enemy applications wer cancelled, reprisals would certainly follow, and British appli- cations for patents in enemy countries would be annulled ; neither side would benefit.

During the war royalties payable to enemy patentees have been lodged in the hands of the Public Trustee in this country; presumably a similar arrangement obtains in enemy countries, and the disposal of these funds will b a matter for the Peace Conference. If no such reciproca! arrangement existed, it would obviously be out of the question to pay any part of such funds to the enemy.

As the Board of Trade representative remarked, the subject is hedged round with difficulties, and no step should be taker without the fullest consideration of the interests concerned, and the U ssible results of such action.

124 THE ELECTRICAL REVIEW. [vo'. 83. No. 2,121, Aveusr 9, 1918.

AN ELECTRICALLY-WELDED SHIP.

PARTICULARS are now available of the interesting—and completely successful—experiment in rivetless shipbuilding carried out at a shipyard on the South-East Coast. The first steel vessel constructed entirely without rivets was recently launched in the presence of Lord Pirrie, the Con- troller-General of Merchant Shipbuilding, and other representatives of the Admiralty and the War Office. She has since been in service with full cargo during exceptionally rough weather, and has answered satisfactorily in every way to the severe tests imposed. .

The object of the experiment, to which considerable importance was attached by shipbuilding authorities, was to prove the ability of welded construction to withstand the strains peculiar to a ship at sea. This principle having been established, it is not proposed altogether to dispense with riveting, which in certain sections is cheaper and quicker than welding ; it is intended, however, that future vessels should be a combination of riveting and welding. The United States Shipping Board, for instance, having been in close touch with the experimental work, is making arrange- ments for the construction of a number of 10,000-ton standard ships in which the use of rivets will be reduced to 2) per cent. of the number originally required.

The recent progress achieved in electric welding by means of the flux-coated metal-electrode process, and its successful use at Admiralty Dockyards and elsewhere in the construc- tion of fitments and superstructures of various vessels, led to permission being obtained for the erection of a standard barge, with riveting eliminated and electric welding sub- stituted throughout. Such a craft is exposed to considerable rough usage in dock, besides being subjected to severe towing strains. In order to utilise material already avail- able on site, this barge differs in no way from the standard riveted type with lapped joints, excepting that the hull- plates were arranged for clinker build and plate edges joggled to permit horizontal downward welding, in order to reduce the amount of overhead work, which is more difficult to execute.

The vessel to be welded was 125 ft. between perpen- diculars and 16 ft. beam, with a displacement of 27% tons. The hull was rectangular in section amidships, with only

Fic. 1.—ViIEw ALONG DECK OF VESSEL, SHOWING JOINTS IN DECK PLATING AND HATCHWAY COAMINGS.

the bilge-plates curved. It was built up of 71 transverse frames, and contained three bulkheads, those fitted fore and aft being watertight and the one amidships non-watertight. The shell-plating was } in. and ,'; in. thick. All joints were lapped in the manner described.

Curiously, the first day’s work was poor, thgugh all the operators were first-rate men. with extensive experience of electric welding in shops, minor repairs, and structural work at shipyards. This was probably due to the novelty of the undertaking and to the position—lying flat on the kee]l— which they had to adopt to get at the joints. In a few days, when the men became accustomed to the job, the speed and quality of the work improved to equal workshop standard practice. With the more difficult welding. such as the vertical butt joints on each shell-plating, and over- head work undeyneath the keel and on bilge-plates, it was noted that the quality of the welds was excellent. For this

overhead work special electrodes were employed, and proved well worth the slightly increased cost. All water-tight joints up to and including the underside of bilge-plates were continuously welded both inside and outside, the other watertight joints being welded continuously on one side and tack-welded on the other. On the shell-plating, the continuous welding was on the outside in all cases. For internal non-watertight joints and frame construction, tack welding was adopted, the length of welding being carefully calculated to give a margin of strength over a similar riveted joint.

Taking all positions of work into consideration, tli average speed was 4 ft. per hour at the commencement, while towards the end of the work an average of 7 ft. an hour was easily attained.

As to the comparative cost of the electric-welded and riveted barge, in labour, 245 man-hours were saved in construction, which can easily be improved on in future

t

Fig. 2.—INTERIOR OF VESSEL, SHOWING ATTACHMENT OF SID! AND BILGE PLATES AND LONGITUDINAL STRINGERS TO TRANSVERSE FRAMES.

work. More than 1,000 lb. of metal was saved, owing to the absence of rivets, but greater economy will result when the design is modified to suit electric-welded ship construc- tion. The total cost of welding was £301, detailed as follows : electrodes, £178 ; electrical energy, £61 ; men’s time, £62.

It is realised by Admiralty experts that the proportion of cost for electrodes is high, but this is mainly due to the present limited demand. Demand and competition will have the usual effect, and should reduce the cost of this item by at least 60 per cent. It will then be possible to build a vessel of this size with an estimated saving of from 25 to 40 per cent. of time and about 10 per cent. of material.

As a result of this demonstration, a new design of barge has been prepared, in which it is proposed to incorporate electric welding and riveted construction to the following extent :—7o be Welded: Coamings, shell seams to frames, deck butts to beams, bulkheads (including boundary bars), keel plate butts to be welded overlaps, and after shell-seams welded.—7Zo be Riveted: Floor riveted to frames, beam knees to frames and beams, frames clear of shell seams.

Standard Magneto Drive-shaft and Coupling Dimen- sions in America.——At the recent summer meeting of the American Society of Automotive Engineers, the report of the Engine Division of its Standards Committee was adopted. It was stated that the nominal drive-shaft diameter and length and the distance from the drive-shaft to the magneto shaft end for agricultural tractor engines had already been standardised. In order to complete the present standard the following were recommended :—(1) The magneto drive-shaft shall be of selected cold-rolled material, } in nominal diameter. The diameter limits at the coupling end shall be 0°750 in. and 0°749 in.; (2) couplings for engine magneto drive-shafts shall have bore limits of 0°7505 in. and 0°7495 in, and shall be fastened with a key. In placing the limite on coupling bores it was ascertained that standard reamers had a tolerance of plus or minus 0°0005 in. It will be noted that a coupling with a 0°7495 in, bore is a press fit of 0°0005 in. on a shaft 0°750 in. in diameter. ,This is the extreme case, and is not considered objection- able, but preferable to a loose fit with a larger coupling.

Vol. 8:

THe [i dealt w old-star facture such. to incr workin and we suppose restrict still ex mittee place v mation an utt obtaini The possibl may be &e., b ( juite C should motive steam carriec anticiy more t geyera 80 pe a con efficie cent., Comn H.P.-b cent. | Ass van b and. t 20 pet the he the c two-tl salvat distil there fuel, woulc than in me gas ¢ the n stean of la pract If units amovu gas effici cent. cent. princ adde In tl to tl wast gases Is savil whic attit burd of th the stear

Vol. 83. No. 2,124, AuGusT 9, 1918.]

THE ELECTRICAL REVIEW.

125

THE FUTURE OF COAL USING.

By W. H. BOOTH.

THE Interim Report of the Reconstruction Committee dealt with the question of power almost entirely from the old-standing view-point of the man who wishes to manu- facture energy in the shape of electricity, and to sell it as such. One of the objects of. the Committee appeared to be to increase the amount of power used per head of the working population, so that output per head may be increased and wages may be higher—all of which, of course, pre- supposes an agreement with Trade Unionism that the wilful restriction of output which prevailed prior to the war, and still exists to a large extent, shall cease. But the Com- mittee further desires that the increase of output shall take place without any increase in coal consumption—a corsum- mation devoutly to be wished, and only to be reached by an utter abandonment of the parochial methods hitherto obtaining.

The report makes a certain limited reference to the possible conservation of the valuable by-products which may be obtained from coal, in the shape of oils, motor spirit, &c., before using such coal as fuel; but the matter is left quite open, and no line is indicated on which such by-products should be conserved. Thus the question of the future motive power of a heat-electrical works is left open as between steam and internal-combustion engines. Thus we are not carried much further along the road of economy, and the one anticipated factor in arriving at a better economy is nothing more than our old friend the big power station with huge geyerating sets. With a maximum boiler efficiency of 80 per cent., a thermodynamic efficiency of 20 per cent., a conversion efficieney of 90 per cent., and a transmissiog efficiency of 80 per cent., the overall efficiency is 114 per cent., and it is extremely doubtful of realisation. The Committee’s anticipated figure is 1°54 lb. of coal per H.P.-hour delivered at the consumers’ terminals, or 11°8 per cent. if the coal value is taken at 14,000 8.TH.U. per Ib.

Assuming that the Committee’s figure of 1°54 lb. of coal van be made good, or 21,560 B.TH.U. per terminal u.P.-hour, and. that a fifth-ef this is lost up the chimney and even 20 percent. of the remainder isconverted into electrical energy, the heat in the steam will be 17,248 units, and the heat in the condensing water will be 13,800 units, or practically two-thirds (64 per cent.). Apart, then, from the possible salvation of by-products by some system of low-temperature distillation and the use of the caked residue under boilers, there would still be lost two-thirds of the heat value of the fuel, and, with a distillation system for residuals, there would be large volumes of non-condensable gases of more than ordinary producer-gas heat potential to be consumed in metallurgy if possible, or, failing convenient disposal, by gas ehgines producing electrical energy and feedimg into the mains. Here there are at once found side by side the steam turbine and the large gas engine, for only gas engines of large power would, it is presumed, be regarded as practicable.

If gas engines should be selected for the main power units, their coal consumption per terminal H.P. would not amount to more than 1 lb., seeing that the efficiency of a gas producer should exceed that of a boiler, and that the efficiency of the gas engine, if not yet more than 25 per cent., or thereabouts, may be anticipated to become 30 per cent. when the fuel is fed to the engine on the Diesel principle of high-pressure pure air compression, with fuel added into this compressed air by a separate compressor. In this case, therefore, there would still remain waste heat to the amount of 9,200 B.TH.U. per terminal H.P.; this waste heat being about equally divided between the exhaust gases and the jacket water.

Is this vast amount of waste heat to be saved? Is it worth saving? Is it possible to save it? These are questions which should not be summarily dismissed in a non possumus attitude, as they represent what will be the national burden of responsibility for, in each case, about two-thirds of the heat value of the fuel used, though for the gas engine the total fuel is assumed at two-thirds that used by the steam engine, and the waste heat is, therefore,, four-ninths,

The problem in some respects is an easier one with steam power.

However regarded, the problem of saving the waste heat is apparently one which puts the big power. station out of consideration if the enormous amount of waste heat can be usefully conserved,

If it cannot so be conserved, and it is somewhat to be feared that this is likely to be the attitude of the big-station advocate who will not listen to anything which would put the big station out of the field, there still remains the question whether the super-station is altogether advisable. The presence of a super-station means an enormous concen- tration of coal transport facilities, and it represents also an easy target for an enemy. International compacts would be unavailing; it would be fatal to generate energy at so few points that concentrated aeroplane attacks could seriously disorganise any large fraction of our manufacturing capacity, and what. would be the effect of a possible invasion which might sever the main transmissions ? Whether regarded politically, technically, or economically, the problem demands much .careful thought and very open minds. It cannot be dealt with in an off-handed manner by any pre-final ideas as to means or systems, for the possible thermal and chemical economies are vast indeed, and unless future wars are. to be rendered impossible, the national safety must come first.

There does not seem to be much information of a reliable order on the question of the heat consumption of a household or an individual, apart from what is represented by electricity. '

Probably no electric light company can state the total number of persons served by it, though this may, perhaps, be approximated as five times the number of dwelling houses, which surely is known to some accuracy. It should, there- fore, be possible at once to state the electrical consumption per head in various classes®of residential areas. Given a means of so arranging electrical supply that waste heat can be supplied to all households concerned, it would seem that on a sound system of heat distribution within a limited radius an enormous fuel economy would be secured, for the great fuel consumers are the fires in living rooms and the kitchen range, both of which appliances send not far from 95 per cent. of their heat up the chimney.

Is electricity to be sent out at a cheap rate from huge Stations, or from smaller stations exposed to less danger of interruption ? In this second case it would almost appear that no, great effort need be made towards motive efficiency, for the heat demand would probably outrun the heat supply.

Real economy would result from a central communal heat supply, and electricity would be a secondary product to heat, or might very easily become so, and one result of this would be that simpler and cheaper machinery might be used. The writer has supplied such cheap machinery when salled on to pump water at 50° F. to be used in a swimming bath at 70°. The wasteful little steam engine with a sur- face condenser could only heat the water to 60°, and further direct boiler steam, added the other 10°. Engine economy would have been wasted capital. It is to this end that central house heating should aim ; and with this to consider, and the possible superiority of low-pressure boilers and simple machinery, the actual overall economy would be enhanced, for the cost of attendance, repairs, oil, and waste would all be minimised. With the super-station the present wasteful domestic fuel problems would continue.

Electric Vehicle Progress.—According to the Electric Vehicle Section of the N.E7L.A., New York, the Norwegian Govern- ment has placed initial orders with American manufacturers for 50 heavy-duty electric trucks, to be used in various communities for the distribution of food which must be distributed in such a way as to avoid waste and spoilage and to assure minimum transporta- tion costs. In Norway, gasolene, when procurable, costs $1 per gallon and electricity 2 cents per KW.-hour. The electric vehicle successfully competed with the gas car when gasolene cost 15 cents per gallon and electricity 5 or more cents per KW.-hour. Many Norwegian cities have adopted electric vehicles, large orders being placed with American manufacturers. Electric trucks are also being successfully operated by a number of commercial concerns, and demands for electric passenger cars are in excess of shipping facilities.

The Gloucester E,L. Committee has decided to purchase an electric lorry for handling coal and ashes

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‘THE ELECTRICAL REVIEW. [vol. 83. No. 2,124, Aveusr 9, 1918.

MINING ELECTRICAL ENGINEERING,” , ;

By CHRIS. JONES, M.I.E.E.

Ir has for some years past been recognised that electrical power is the motive power par excellence for mining work, and that an efficient and reliable supply of electricity is in- dispensable to the prosperity of these industries, and with the progress of time the successful working of our mineral fields will more than ever be dependent on transmitted power. It is, therefore, of vital importance that those of us who ure engaged at home should exert every effort towards in- creasing the efficiency and reducing the cost of generating, distributing, and applying the electrical power in mines and kindred industries, at the same time aiming at the mainten- ance and improvement of safety, simplicity, and reliability.

This paper will be confined to a consideration of the elec- trical system.

The question of a standard frequency is of great import- unce, especially so in view of the linking-up proposals of various supply systems. While frequency changers are suc- cessfully in use at collieries in this country, the writer thinks that they are best avoided, as ‘they introduce high