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PUBLIC RECORD OFFICE
Reference :-
MELEC.O. 885
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ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC- COPYRIGHT PHOTOGRAPH-NOT TO
PUBLIC RECORD OFFICE, LONDON
23 November 1896.]
Chairman-continued.
Dr. MUIRHEAD.
985. That is Vancouver to Fanning Island ?- Assuming the rate of transmission on that section 70 letters per minute, the rate throughout the system would be about the same.
986. There you cannot give even approxi- nately to the Committee how long a message would take to go from London to Australia by that route? That is across Canada?
987. Yes. There would not be more than a quarter of an hour's delay. It is a difficult It presumes a knowledge question to answer. of the Canadian lines, and a knowledge of the lines in Australia. The cable part of it would be regulated by the longest spans 70 letters per minute by adopting the automatic curb method of transmission,
988. Can you tell the Committee the present time that it takes a message to go from London to Australia by the Eastern route, direct line?- It has been done in a quarter of an hour. There are representatives of the Eastern Telegraph Company who can give evidence on this point better than I can.
989. Do you know how many repeating stations there are by the present direct line to the East? Yes, 14.
Sir Donald Smith.
990. How much of the 15 minutes from London would be required for the transmission of the message from Vancouver to Australia? ---From Vancouver to Australia?
991. From Vancouver to Australia. - Very little. How many transmitting stations are there?
992. Vancouver,
Chairman.
Fanning Island, Fiji, Norfolk Island, and Brisbane ?With a good system at these intermediate stations, and good management, I should say five minutes.
Sir Donald Smith.
993. Five minutes from Vancouver to Aus- tralia ?- From Vancouver to Australia.
994. I asked because, some four years ago, I think it is, I had an opportunity of telegraphing to Vancouver and Victoria, British Columbia, during about an hour and a-half, and we had the replies to the questions asked within three or four minutes continuously. That was by the Commercial cable.
Chairman.
995. Have you any doubt as to the laying of a cable from Vancouver to Fanning Island being practicable ?-One would require to have a good knowledge of the bottom between the points to answer that question. There is, I believe, mechanical difficulty in handling cable larger than this proposed 500, 320 cable. I have heard that the Anglo-American Telegraph Com- pany's last cable was rather difficult to lay for mechanical reasons.
996. What does the difficulty arise from ?— The stiffness of the conductor. That is what I have heard. I am not an expert in laying cables, and therefore cannot give evidence on such points.
997. You are not an expert on the question of laying cables ?-No.
998. You have told the Committee generally
Chairman--continued.
[Continued.
that in making such a cable, your advice is to put in as much copper as possible? Yes.
999. Can you give the Committee your opinion as to what would be the proper weight of copper and guita-percha per nautical mile for that section from Vancouver to Fanning Island? - I think a cable of 650 copper per knot and 400 gutta-percha per knot would be inore serviceable than the proposed one of 500 copper aud 320 gutta-percha per knot. My opinion is that a core as the Anglo- cable having the same American Telegraph Company's 1894 cable would be more serviceable in the event of extra pressure of traffic from, say, a total interruption of the present lines to Australia.
1000. And that would give a speed of Working with the same signals as you would get with the proposed cable of 500 copper and 320 gutta-percha at the rate of 70 letters per minute, a speed of 95 letters by automatic curb transmission or 641 by the ordinary method of transmission.
Mr. Murray.
1001. What is the actual speed of that cable? -The trans-Atlantic cable?
1002. Yes. It is about 1,900 miles long, and they are working, I believe, at the rate of 46 words a minute, each way.
Mr. Jones.
1003. Have you any experience respecting the cost of maintenance of these long cables?—No.
1004. Do you think there would be any great risk in having only one cable, or should there be two? It is better to have two cables so that there may be less chance of a total interruption of traffic.
1005. And a smaller cable from Fanning Island would be able to take all that would go over the longer cable-A less expensive core from Fanning Island to Australia would transmit all that the long cable could take.
1006. The longest span would convey so many words per minute? - Yes.
1007. But a smaller cable would carry it ou from Fanning Island to Australia ?—Yes.
1008. And a less expensive cable? Yes, a much less, if you decide to carry only Australian traffic. That is to say, if you decide not to have any section of cable laid faster than the reduce longest span will be, then you can considerably the total cost.
1009. Exactly; that is what I wanted to arrive at. But if you wanted to carry interme diate traffic between Fanning Island and Australia, it would be necessary to have the shorter cables faster than the longest span.
Mr. Murray.
1010. What are the elements of the specifica- tion that you would recommend. Is there any- thing besides the weight of the conductor and the weight of the insulator?-The resistance of the conductor and the capacity of the core.
1011. And that is all you need specify?—I
think so.
1012. And from those two elements you can deduce the absolute speed – Ye•,
If
1013. With absolute certainty?—Yes. you give me the dimensions of any proposed cable I will produce the probable signals at a certain speed in my laboratory on an artificial cable of the same electrical retardation.
23 November 1896.]
Dr. MUIRHEAD.
Mr. Murray-continued. 1014. And no possible element of error can come into that ?-No. I hope you understand that it is the automatic curb method of trans- mission which gives the higher speed I have given in this evidence; the ordinary method of transmission gives much lower results.
1015. About 50 per cent. lower?- Forty or 50 per cent. increase of speed is obtained by using the automatic curb transmitter.
Chairman.
1016. Could you tell the Committee what is the percentage of increase of speed in letters that has been achieved by the introduction of the automatic system over any given cable :—Over 40 per cent.
1017. Forty-That is a safe figure.
1018. Taking the cable you recommended to us just now for this Fanning Island section, what would be the maximum amount of business in a year such a cable could take; in words? -- In words: five letters or nine?
The average number of letters per word in Eastern traffic is about nine; in Western traffic the words are shorter, I believe.
1019. Why do you ask me whether five or nine? The tariff charges are given at so much per word.
1020. Is it a true standard? -Your question just now bore on traffic; it is necessary to know the average number of letters per word.
1021. Do you consider that five is not a proper standard for practical working?-It turns out not to correspond with the experience of the Eastern companies.
1022. And what is the experience of the Eastern companies?-A little over nine letters per word in the code traffic; less in press work.
1023. And is that owing to the substitution of code words for ordinary words ?—Yes.
1024. That average is due then to three operating reasons: the fact that by the Tele- graph Convention a word is limited to ten letters? - Yes.
1025. The general introduction of code words? -Yes.
1026. And the dropping of the small conjunc- tions, such as "and," and so on ?—Yes.
1027. Then on a basis, let us say, of nine letters, what is the maximum business such a cable could carry through in a year?- This cable? 1028. The cable of 500 and 520 lbs. to the core. From here to Australia ?
1029. Yes. Viá Canada?
1030. Yes. Now comes the question of how much time is to be put down for preambles. According to the Eastern companies, as much time is given to preamble, &c., as to the messages. Must I calculate on the basis of the experience of the Eastern companies?
1031-2. Yes. On the assumptions: 1. That only average operators are employed; 2. That the average length of code words is nine letters; 3. That half the time of transmission is occu- pied with preambles, calle, services, and other unpaid matter; and, 4. That duplex automatic curb transmission is adopted, a cable 3,600 knots in length of a core weighing 500 lbs. copper and 320 lbs. gutta-perche per knot would earn eight paying words per minute, The same length of
[Continued,
Chairman-continued, 552 copper and 368 gutta-percha core would caru nine paying words
per minute. Mr. Murray. 1033. Then you allow half the time for pre- fixes and service signals, and so on ?--Yes,
Chairman,
1034. But on the basis of four words per minute, how many words would that give as a maximum in the course of a year, roughly ?—In & year?
1035. Yes.-Including Sundays? 1036. Continuous working.
traffic.
-
Continuous
1037. Very well; will you give me the maxi- mum for a year, of week-days only, at 18 hours working a day, at a net working rate of four words per minute?-Each way?
1038, Yes. That is eight words? 1039. Eight words? Fifty-one thousand eight hundred and forty words per week; 52 weeks, public holidays I suppose would have to be deducted?
-
-
1040. Oh, I think I should have 52 weeks.- Two million six hundred and ninety-five thousand six hundred and eighty.
1041. A cable of 500 lbs. of copper and 320 lbs. of gutta-percha per nautical mile, on the section from Vancouver to Fanning Island, would give in 52 weeks, excluding Sundays, and reckoning 18 working hours to the week-day, at a rate of four words per minute ench way, or eight words per minute in all, a total of 2,695.680 words in the year? Yes, on the assumption that half the time of transmission is occupied with preambles, &c., and that the average paid word is of nine letters.
Mr. Jones.
1042. What difference of time do you estimate there would be in sending a message viá Van- couver and Fanning Island, as between the pre- sent existing system, over the Eastern extension? -I should say the speed would be greater on account of the fewer number of transmitting stations on the Pacific.
1043. What difference do you estimate between the two routes ?—That is a difficult question to answer. It would make a vast difference, I should say, because the greater the number of trans- mitting stations the greater the liability to error, and, consequently, the greater the percentage of repetitions, which all tend to delay matters. cannot say how much difference.
I
1044. That is to say, there would be a vast difference between existing lines and the contem- plated route?—Yes, I should think so, but I cannot tell you how much; it all depends on the way in which the traffic is handled.
Sir Donald Smith,
1045. May I ask why it should require 10 minutes for transmission from England to Vancouver and only five minutes from Vancouver to Brisbane across the Pacific?-1 had in my mind the fact that an Independent Company would take the traffic from England to Canada, where it would be handed over to a land ling company for transmission to Vancouver.
K The Witness withdrew,
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23 November 1896.
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