Submarine cable laying and repairing

t> SUBMARINE CABLE LAYING AND BEPAIKING.
jerk the sounding line to give the cut, especially if the knife is
at all blunt or out of adjustment, and this is liable at times to
break the line. To avoid this possible danger to the line
Mr. Edward Stallibrass has devised a detaching gear in which
the wire sling is simply thrown oflF its seat instead of being
cut (Fig. 4). The ring at the top is one with a plunger, which
carries a small stud working in a slot in the upper tube. When
the apparatus is suspended from the ring the plunger takes the
highest position (as in the figure) and the sling supporting the
Aveight is held in the notch above the tumbler. On striking
Wire Sling
for Weight.
FiQ. 3.—Silvertown Detaching Gear.
bottom and the wire slacking, the plunger is pulled down by
a spiral spring inside, and the stud, descending with it,
engages between the two projections of the tumbler. When
picked up on board ship the tumbler is turned by the
stud so as to present an inclined surface to the sling, causing
it to roll oflf and release the weight. The form of water
and mud collecting tubes are similar to those in the Silvertown
apparatus.
When it is not required to recover a sample of the
bottom water the large tube is dispensed with and a lin.
iron gas pipe substituted, as at A B, Fig. 5. The tube passes