Weal URE 
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THURSDAY, APRIL 15, 1897. 
SUBMARINE CABLE LAYING AND 
REPAIRING. 
Submarine Cable Laying and Repairing. By H. D. 
Wilkinson, M.LE.E. Pp. 4o1. (London: The Elec- 
trician Printing and Publishing Company, Ltd., 1896.) 
HIS is not a scientific treatise on the electrical 
principles involved in submarine telegraphy ; it 
covers, however, rather more ground than is set forth in 
the title, being also some sort of text-book for the elec- 
trician engaged in cable work. Mr. Wilkinson has 
treated his subject entirely from an up-to-date point of 
view, without attempting to show what has led to 
the present state of affairs, which, by the way, are 
the same—fundamentally speaking—as they were some 
thirty years ago. The method of working cables by 
machine transmission is not dealt with here; neither 
must the reader expect to find any matter relating to the 
duplex system of Messrs. Muirhead and Taylor, or that 
of others. 
That portion which bears on construction might be 
more ample with advantage, especially as there are many 
engaged in submarine telegraphy who have never seen a 
cable made from start to finish. This remark particu- 
larly applies to the preparation and construction of the 
component parts of the insulated core, whether of gutta- 
percha (by Willoughby Smith’s process or otherwise) or 
of vulcanised india-rubber, as well as of their collection 
in the state of nature. Much useful instruction is afforded 
with regard to the copper composing the conducting wire 
in a paper on electrical conductors, read by Mr. W. H. 
Preece, F.R.S., before the Institution of Civil Engineers 
in 1883.1 Mr. Wilkinson has well, though briefly, de- 
scribed the constitution and application of the jute 
serving applied to the core of the iron sheathing, and of 
the outer covering, besides that of Bright and Clark’s 
compound. The author has nothing to say on the 
subject of hempen cables, as suggested by Bullivant 
and afterwards by Trott and Hamilton. This silence is, 
however, justified by the fact that though a trial has been 
given to the latter in mid-Atlantic, the experiment has 
not culminated in further use. A cable without any iron 
armour appears, on the face of it, to be admirably adapted 
to recovery from great depths. The best quality of 
hemp decays, however, in salt water, even when by itself, 
to an extent sufficient to make the picking up of such a 
cable an almost impossible feat—not to mention the 
difficulties in the way of laying it down at a suitable 
angle. 
No doubt Fig. 27 is intended to represent the ordinary 
close-sheathed type of the present day, but it rather 
suggests one of the alternate iron and hemp (low specific 
gravity) combinations, such as were once in vogue with a 
view to easy laying and recovery, but which, it is satis- 
factory to know, has long since been abandoned owing to 
its lack of durability. 
Mr. Wilkinson gives us a strong chapter or two re- 
1 Mins. Proc. Inst. C.E., vol. xxv. 
NO. 1433, VOL. 55 | 
, velocity. 
garding submarine survey and sounding work, with good 
descriptions of the apparatus employed. At the present 
time, however, the line is supplied in lengths of as much 
as 7000 fathoms, thus rendering splices quite unnecessary 
in all depths so far dealt with. Nowadays, we also find 
that, provided a sinker is selected with sufficient weight 
for the depth, it will descend at a rate which will ensure 
the striking of bottom being readily observed. It is, 
therefore, no longer essential that the drum holding the 
wire should be particularly light ; indeed, it is usually 
made of a sufficiently substantial character to permit of 
the wire being coiled direct on to it. Moreover, Lord 
Kelvin’s plan of balancing the weight of wire outboard 
by weights added to the brake, has long since been 
abolished. The only proper method of preserving speci- 
mens of the bottom—partly for after-examination under 
a microscope—is to force the sample, zmediately after 
recovery, direct from the “sounder” into an open glass 
tube, to be afterwards closed at both ends with corks, 
and hermetically sealed. The sample, when examined 
at any time, is then a true record of the bed of the 
ocean from whence it came. This plan was brought 
forward some years ago by Lieut. D. Wilson Barker, 
R.N.R. The water and mercury piezometers of Mr. 
J. Y. Buchanan come in for notice here. For a 
future edition, Mr. Wilkinson might find profit from a 
study cf Mr. Buchanan’s papers with reference to the 
various sounding and survey expeditions he has accom- 
panied in H.M.S. Challenger, on the west coast of 
Africa and elsewhere. In this connection, the author 
and reader may also be recommended to peruse a paper, 
contributed by Lieut. Anthony Thomson, R.N.R., to the 
Sixth International Geographical Congress (1895), en- 
titled “Remarks on ocean currents, and practical hints 
on the method of their observation.” The importance 
of noting the nature, and measuring the strength, of deep- 
sea currents is better understood now than it used to be. 
It can, in fact, scarcely be over-estimated. In several 
instances of cables, past as well as present, much trouble 
and many repairs might have been saved had these 
matters been duly considered previous to laying. For 
further information regarding sounding work in its con- 
nection with submarine telegraphy, the reader should 
apply himself toa paper on the subject by Mr. Edward 
Stallibrass, in the Journal of the Society of Telegraph 
Engineers, 1887. 
The various systems of landing shore ends under 
different conditions are all well set forth in this book ; 
and, moreover, clearly illustrated. 
Paying-out apparatus is gone into at some length. 
The cardinal principles, as first defined and put into 
practice, are closely identified with the names of Newall, 
Bright, Edwin Clark, Canning, Clifford, Appold, Amos, 
Siemens, Jenkin and Webb. The laws which govern 
the rate of paying out under given conditions are’ 
partially touched on in this treatise, though no reference 
is made to the heated controversy which arose in 1876 
between Messrs. Longridge and Brooks, on the one hand, 
and the late Dr. Werner Siemens, on the other, as to 
whether the friction introduced by a body moving in fluid 
varied as the sgware of the velocity, or merely as the 
It is usually considered that the longitudinal 
BB 
