254
PUBLIC RECORD OFFICE
Reference :-
CO885
7
PUBLIC RECORD OFFICE, LONDON
ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC- COPYRIGHT PHOTOGRAPH-NOT TO
Heavy Shore-end Cable, No. B. 5.
Deep Sea Cable, No. G. 1.
Light In- termediate Cable, No. G. 2.
Heavy In-
12
a suitable compound of tar, and laid on helically. The diameter of each steel wire, when galvanized, is on the average to be 0-276 of an inch, or within 5 per cent. thereof.
The cable to have an outer-protective covering of two layers of tarred jute yarn, with three alternate coatings of compound.
Three nautical miles of this cable are to be supplied.
The cable No. B 5 shall consist of the core B, brass-taped, covered with a serving of tanned jute yarn, to be wetted, sheathed with 15 galvanized soft steel wires, covered with a suitable compound of tar, and laid on hefically. The diameter of each of these 15 steel wires, when galvanized, is on the average to be 0-116 of an inch, or within 24 per cent. thereof. The cable, so far completed, to be covered with servings of tarred jute yarn and coatings of compound, and further sheathed with 12 strands, laid on helically-cach strand composed of 3 galvanized soft steel wires, covered with a suitable compound of tar. diameter of each steel wire forming the strand, when galvanized, is on the average to be 0212 of an inch, or within 5 per cent. thereof,
1
The
The cable to have an outer-protective covering of two layers of tarred jute yarn, with three alternate coatings of compound.
One nautical mile of this cable is to be supplied.
The cable No. G I shall consist of the core G, covered with a serving of tanned jute yurn, to be wetted, sheathed with 22 galvanized tempered steel wires, covered with a suitable compound of tar, and laid on helically. The diameter of each steel wire, when galvanized, is on the average to be 0·080 of an inch, or within 24 per cent. thereof.
The cable to have an outer-protective covering of two layers of tarred jute yarn, with three alternate coatings of compound.
· 3,556 nautical miles of this cable are to be supplied.
The table No. (i 2 shall consist of the core G, brass-taped, covered with a serving of tanned jute yarn, to be wettel, sheathed with 20 galvanized soft steel wires, covered with a suitable compound of tar, and laid on helically. The diameter of each steel wire, when galvanized, is on the average to be 0'10-4 of an inch, or within 24 per cent. thereof.
The cable to have an outer-protective covering of two layers of tarred jute yarn, with three alternate coatings of compound.
Five nautical miles of this cable are to be supplied.
The cable No. G3 shall consist of the core G, brass-taped, covered with a serving of termediate tanned jute yarn, to be wetted, sheathed with 12 galvanized soft steel wires, covered with a suitable compound of tar, and laid on helically. The diameter of each steel wire, when galvanized, is on the average to be 0212 of an inch, or within 5 per cent. thereof.
Cable, No. G. 3.
Light
The cable to have an outer-protective covering of two layers of tarred jute yarn, with three alternate coatings of compound.
16 nautical miles of this cable are to be supplied.
The cable No. G 4 shall consist of the core G, brass-taped, covered with a serving of Shore-end tanned jute yarn, to be wetted, sheathed with 12 galvanized soft steel wires, covered with a suitable compound of tar, and laid on helically. The diameter of each steel wire, when galvanized, is on the average to be 0.276 of an inch, or within 5 per cent. thereof.
Cable, No. G. 4.
Непту
Cable, No. G. 5.
The cable to have an outer-protective covering of two layers of tarred jute yarn, with three alternate coatings of compound.
22 nautical miles of this cable are to be supplied.
4
The cable Na, G 5 shall consist of the core G, brass-tapel, covered with a serving of Shore-end tanned jute yarn, to be wetted, sheathed with 20 galvanized soft steel wires, covered with a suitable compound of tar, and laid on helically. The diameter of each of these 20 steel wires, when galvanized, is on the average to be 0104 of an inch, or within 24 per cent. thereof. The cable, so far completed, to be covered with servings of tarred jute yarn and coatings of compound, and further sheathed with 12 strands, laid on helically-cach strand composed of three galvanized soft steel wires, covered with a suitable compound of The diameter of each steel wire forming the strand, when galvanized, is on the average to be 0.212 of au inch, or within 5 per cent. thereof.
tar.
The cable to have an outer-protective covering of two servings of tarred jute yarn, with three alternate coatings of compound.
One nautical mile of this cable is to be supplied.
13
III-GENERAL CONDITIONS.
The core shall be manufactured in cuils, each coil containing a length of not less Number- than one nautical mile, and these coils shall be numbered, labelled, and registered, and a record shall be kept of the portion of the cable into which each original length of core is coils of
ing and re- gistering placed.
voru.
The length and the weight of the conductor and the dielectric of each coil shall be Margin given. A margin of 5 per cent. over and under the specified weights shall be allowed, allowed in but the mean weight of the whole of the core supplied must be at least equal to the Conductor specified weight of the conductor and of the dielectric respectively.
weight of
and
Dielectric.
The gutta percha employed to be of good, hard, and pure quality, not to soften at Gutta to low a temperature, and the several layers to be put on in such a manner as to form a
Percha solid homogeneous covering, free from air-bubbles and flaws.
covering.
The core, when completed, shall be submitted for testing to the Government Testing of Engineers in coils of the original length of not less than one nautical mile, and no coil of Core, core shall be served with jute yarn or sheathed before it has been tested and found to fulfil the conditions specified herein and approved of by them.
The conductivity of the conductor shall be equal to at least 98 per cent. of that of pure copper, that is to say, the electrical resistance, per kuot-pound, shall not be more
than :-
1,217 ohms at a temperature of 75° Fahr., and 1,178
60°
resistance of the dielectric, per cube-knot, after one minute's electrifica- less than :-
1,900 megohms at a temperature of 75° Fahr., and 6,200
The specific tion, shall not be
60°
"
nor more than :
:)
11,000 megohms at a temperature of 75° Fahr., and 35,870
60°
+
"
"9
Inicrofarad.
The specific capacity of the dielectric, për cube-knot, shall not be more than 0.06 The resistance per nautical mile of the conductor shall not be more than :~-
Cure
A.
13.
6.
13
7.66
12.6
7.42
2-6 2.52
Ohms at a temperature of 75° Fahr.
60°
99
ון
The resistance per nautical mile of the dielectric shall not be less than :—
C'ore
A.
B.
G.
350 1,140
310 1,030
270 870
Megohms at a temperature of 75° Fahr.
60°
11
19
ID
nor more than ;-
Core
A.
B.
G.
2,020 6,600
1,850 6,000
1,550 5,000
Megohms at a temperature of 75° Fahr.
60°
"
"
The capacity per nautical mile shall not be more than :~~~
Core
A.
B.
G.
•327
360
427
Microfarad.
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