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PUBLIC RECORD OFFICE

Reference :-

[C.O. 885

لسائل.

6

ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC- COPYRIGHT PHOTOGRAPH-NOT TO

PUBLIC RECORD OFFICE, LONDON

18 November 1896.]

lying

Mr. Murray- continned.

Mr. LUCAS.

on the bottom?--It would not be lying ou

the bottom.

877. Then you adhere to your original view, that it is scarcely practicable to lay a cable of this length securely without a much more elaborate survey than has hitherto been made? -I certainly think that no telegraph engineer would give you a different opinion from that. The place should be carefully surveyed before the cable is put down if you wish the property to be secure and safe.

878. The four firms that did tender do not seem to have laid much stress upon that; they seem to have been prepared to estimate and to proceed with the business without waiting for any further survey ?-1 cannot account for that.

879. Then, as to the weight of the cable, is that rule for speed, which you have laid down, absolute, or does it depend upon the composition of the cable itself and the working of it; I mean can you calculate by that rule the speed if you are given only the weight of the copper and the weight of the insulator and the length!-- Yes.

880. Absolutely?—Yes, if the copper resistance and the electrostatic capacity are given.

881. You have kindly given us here the details of these existing cables and the K.R. for cach of them. Could you deduce from that the speed per minute?—Yes, I could work out the theoretical speed per minute from that, but the actual speed might vary from the theoretical slightly. It depends on what instruments are used, and upon the system which is worked, anl to some extent upon the clerks, unless it is worked automatically; all these things make Bome slight difference.

882. What margin would you allow for that variation? These questions of the practical working of cables I think would be better asked of one of the Telegraph Company's representa- tives. My work does not lie in that direction.

883. Did draw

you

these figures?--Yes. up 884. And you do not think that there would be very much variation from the speed that you would compute from those figures due to either working or the composition of the cable?

CL

Speed" is a very elastic term, and people may nake what they like of it. It is very much like selling feathers by a quart measure. Any- one who wants to show you what a lot you are getting for your money could drop those feathers into a quart measure with a very light hand, and anybody who wishes to point out to you how little you are getting for your money could ram those feathers in pretty tight, and that you may take it is the same with speed.

Mr. Gillies.

885. But is not that the number that they are arguing on? They propose to give you a specific thing and they are not giving you any more than they pretend to give you, for instance, five letters? Yes, the attainable speed with press messages at the greatest possible pressure with the most experienced clerks and under the most favourable circumstances. That is one kind of speed. Then there is the speed of ordinary

Mr. Gillies continued.

[Continued,

traffic in code messages, which would be consider- ably less.

886. Then is there no meaning to be attached to the expression twelve words, or twelve letters, or fifteen or eighteen; is there no meaning to be attached to that ?-Within a certain margin there is; but you must state whether the speed means the attainable speed, or whether it means the speed of ordinary working with traffic. These are two very different things.

887. Then how do you explain that one cable is made supposed to have the capacity of sending along so many words a minute, another cable can do more than that, and a third cable can do better than either of the others, is it not owing to the capacity of the cable? The cable is constructed in a particular way to have a capacity to send along so many words and so many letters in the minute ?--If their K.R. is It is a the same their speed will be the same.

total electrostatic capacity question of the multiplied by the total resistance and nothing else if their K.R. is the same it only depends on what kind of instrument you work with, what kind of clerks you have, and whether worked under very favourable conditions, or worked with the ordinary code traffic.

888-9. But the character of the cable deter- mines the speed of the cable, as I understand?- Yes; the K.R. of the cable determines the speed.

Sir Donald Smith,

890. But in the case of the Pacific cable, their tenders have been given for a cable of 12 words? --Yes.

891. Tenders have also to be given for a cable What are we to understand by of 15 words. that? The conditions were general to all who were willing to tender. What are we to under- stand then by these 12-word cables and the 15- or 18-word cables?—I think that in asking for tenders it would be very much better to definitely ask for a core containing so many pounds of copper and so many pounds of gutta- percha, than to ask for a cable which will be capable of sending any particular number of words, because, as I tried to explain to you, the speed is an extremely elastic term.

892. But the tenders were made, so to speak, on actual specifications made by the Govern- ment; several have tendered for the same work, Are we -that is for 12 words and for 15 words. to understand that the meaning of the tenderers may have been different as regards the meaning of 12 words, and of 15 words? It is too open an expression for tendering upon altogether. It was not even specified whether this meant 12 real words, such as are sent in traffic, or whether it meant 12 reputed words of five letters. There was no specification to tender upon, contractors- were asked to make their own specification, and to go as they pleased in that respect, and I take it that it was done with the view of col- lecting the best possible information and the views of the different contractors, and I think it answered its purpose very well, and it no doubt was of considerable assistance, and threw some But if it was light upon the whole question.

18 November 1896.]

П

Mr. Lucas.

Sir Donald Smith-continued. really question of tendering for the cable, then the first thing that should be done would be to decide what is the cable to be; let us have a specification drawn up, and then ask for tenders, and then the contractors would all be tendering for the same thing,

893. We are told that some of those who tendered were perfectly willing to accept the contract on the terms offered, perfectly willing to carry out the contract, but you seem to look upon it as more of a speculation?—No, I did not use the word.

*94. You did not use the word? - I merely said that they were all tendering upon different specifications, which of course is scarcely to be considered a fair way of tendering.

895. They may not have meant the same thing with regard to the 12-word cable or the 15-word cable, you think? - No; it is not sufficient to merely say how many words a cable should be capable of transmitting,

Mr. Murray,

I

896. But may we assume, suppose we specify a cable of a given weight of copper and a given weight of insulator, may we assume that all cables made by any makers which comply with those conditions would give the same speed?- There is no doubt about that. You specify that the copper is to be pure copper of 100 per cent. conductivity. I take it that no difference can exist in that copper, and whether it is made or ordered through one copper-wire drawer or another, it is to be pure copper: I do not think that you can get any advantage in one case over another. think that is the way to specify for a cable; you say your wire is to be of a certain size, and that it is to be of a certain breaking strain, that it is to be of a certain elasticity. I do not think, as long as a cable is ordered like that, there can be much doubt that whoever you order it from will be kept up to the mark, and will not be allowed to supply anything but what is ten- dered for. That is the usual way. I think in your memorandum you speak of the form in which a contract should be drawn like to hand in the form in which we are accustomed to draw up contracts. It may be some guide to you. It is the form which the Telegraph Construction and Maintenance Com- pany has adopted for many years, It has been somewhat modified in different contracts, but one thing I can say in its favour is that it has never led to any disputes or litigation afterwards. (Form of contract put in.)"

up.

I should

897. May we assume that the electrostatic capacity and the conductor resistance, from which you calculate the speed, will be the same in any cable of any maker?—Of any maker. There is only one kind of electrostatic capacity and only one kind of conductor resistance; it is an ab- solute standard.

898, Well, let us take this illustration. I should infer from the tests of the existing cables that you have given here, that the slowest speed would be on the 1875 cable from Ireland to Nova

See No. 5 in Part II. of Appendix, p. 240.

Mr. Murray- continued.

[Continued.

Scotia, and the fastest speed on the 1894 cable from Valencia to Newfoundland; is that the fact? I daresay that is the fact; the speeds will be proportionate to the K. R.

899. And you would expect that to run all through Undoubtedly it will run all through. There will be some variations, due to the different system of working.

900-1. The K. R. is de luced from the distance, among other things? Yes.

902. What would be the difference in speed between a cable whose K, R. is 78 and a cable whose K. R. is 24?-You are taking the two extremes?

903. Yes, - One is more than double the other.

904. Well, a good deal more. They would be in that proportion.

905. In the proportion of 2-4 to 7-8 ?——Yes.

system

906. We were told, as a matter of fact, that the speed of the 1894 cable of the Commercial Company was 42 words, and the speed of the 1894 cable of the Anglo-American Company was 47, but the K. R. of the first is 42 and the K.R. of the second is 24?- Different companies have a different

of working which might account for that. One company require very great definition in their messages; they want to see every letter formed on the recorder slip; they want great definition; they want, as it were, the handwriting to be very clear; they have sufficient capacity of cables to permit of this being done, and they lay great stress upon having a very clear definition. "Another company may, through being very much pressed, work with very little definition, and at the same time, with very expert operators, they may work with great There is room for a margin of differ- ence of speed in the actual working through cables, say of the same K. R You may take two cables that are of the same K. R.; on one cable you will find that they are working under extreme pressure, and yet they may be working very well though with very little definition, and on another cable where they have other lines at their disposal, they may insist upon working with very great definition.

accuracy.

907. In fact, we must compare like with like? Yes, and that is the reason why a cable is not always worked proportionately to its

K. K.

908. But that raises a difficulty, does it not; if we

are to do nothing more in the speci- fication than specify the weight of the core and the weight of the conductor, how are we to be sure that that will produce the desired result in speed? -

Mr. Gillies.

909. What do you call faults in a cable ?— A fault is technically a leakage in the insulation. 910. And would there never be a leakage in one cable and no leakage in another which may be manufactured by different people ?-Oli, certainly, the specification and the contract for a cable will never permit of any fault in the cable when it is handed over. There is a clause in the contract which I have handed to you which is very stringent in that respect, that the

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