DEEP-SEA EXPLORATION. 
301 
iin old ash bucket filled with tire brick, etc., and the list of available luatcrial may 
be larj;ely extended. 
It old lead can be had, it would be very easy to cast disks weighing troui 10 to L'O 
pounds, which may be used in series, as ou the Baillie machine. In the absence of 
better facilities they may be cast in 0 [)cu molds of ordinary deck sand; a little 
molasses and flour should be added to give greater consistency, wood or metal being 
used for a core. 
Cast-iron, ballast is readily transformed into sinkers; shot, shell, and canister Uiie 
equally available; and small chain or wire rigging made up in suitable coils, chain 
shackles, and pins, links of chain cable, pieces of condemned nmchiiiery, and even sand 
in tin cans or canvas bags may be utilized. Wire is preferable to hemp or manila for 
binding fragments together to form a well-balanced sinker, and it is best for bails also. 
LUGS AND OTHER DEVICES FOR SUSPENDING DETACHABLE SINKERS. 
'I'he lu(/s on detachable sinkers reached their iiresent form through a process of 
evolution. Brooke suspended the shot by slings and washer, as shown with his 
apparatus, and Belknap used the same until I'exieated fouling of Avasher and cylinder 
induced him to substitute wire slings, Avhich consisted of two rings surrounding the 
upper and lower quarters of the shot held in jilace by cross-seizings and two wire 
lanyards, one end secured to the lower ring on the sinker, and on the other end small 
iron rings to receive the lip of the tumbler and insure pi'ompt clearance when it 
trip]ied. This arrangement prevented fouling, but was found to be rather cumbersome 
and required too much time to preiiarc the sinker for use. 
Cast-iron lu</s ou the upper exterior surface of the shot were soon adopted, and 
proved to be a long stride in the direction of simplicity, certainty of action, and 
immunity from fouling. A single Avire bail Avas u.sed, the ends being secured to the 
lugs AAutli large eyes, Avhich permitted it to move freely and even fall away from 
the disengaged tumbler by its own Aveight. The sole disadvantage attending the 
introduction of cast-iron lugs Avas the freiiuent breakages caused by the brittleness of 
the material. 
Bail holes Avere introduced liy Sigsbee, Avho found cast-iron lugs too unreliable. 
They Averecast in the same relative positions on the surface of the sinker, Avhieh insured 
convenient and secure attachments for the bail but did not allow the same freedom of 
movement. 
Iron wire lugs, cast Avith the shot, Avere subsequently introduced and are still in 
general use. They are in the form of Avire staples, cast into the surface of the sinker 
parallel with the axis of the central hole, and project above the surface only far 
enough to afford convenient attachment and free movement of the bail. They are 
seldom broken by rough handling, as the wire becomes thoroughly annealed in the 
jirocess of casting and subsequent cooling, and they can be bent flatly to the surface 
of the shot Avithout injury. 
The wire bails now used with detachable sinkers are of annealed iron wire, No. 8, 
American Avire gauge, and may be conveniently fitted by first cutting them from the 
coil in uniform lengths and bending them over a form to insure a free and uniform seat 
for the lip of the tumbler. 
Sinkers should not be bailed until they are reijuired for use, and Avhen the 
requisite number have been placed in the racks, proceed first to examine the lugs and 
