300 Bulletin, Scripps Institution of Oceanography 
bottom eye of the anchor. Next, the 54-inch manila tag line, which carries all the 
weight, is eased out, and the anchor’s 300-foot wire-rope pennant is payed out 
under slight tension to avoid fouling. When the 300-foot wire-rope pennant is 
completely payed out, the strain is eased onto the mooring wire from the manila 
tag line. Once the mooring wire has the strain, the manila tag line is eut and the 
winch operator starts lowering away under power. After several hundred meters 
of wire are out, the winch is stopped, the motor is disengaged, and the remainder 
of the lowering is done using only the brake. The optimum lowering rate is be- 
tween 150 and 200 meters per minute. The winch operator has to be extremely 
alert, taking into account the roll of the ship and working with it. Failure to do 
this may cause a sharp jerk, which might pretrip the bottom-detecting device or 
even part the wire. Sudden slack in the wire may cause it to jump the sheave, 
usually at the level wind at the winch. If the wire does not part when it jumps 
this sheave, there is a very good chance that it will part in the process of getting 
the wire back into the sheave. It usually takes about 30 minutes to lower the 
mooring wire on a 2,500-fathom station. 
The wire must be very close to vertical when approaching the bottom. If there 
is a noticeable wire angle, the winch is stopped until the ship can maneuver to 
eliminate it. 
Paying particular attention to the amount of wire out and to the depth, the 
winch operator begins slowing down about 200 meters off the bottom so that he ean 
stop the winch quickly but smoothly when the implosion of the glass ball is heard 
on the loud-speaker. If the bottom-detecting device fails to function for any reason, 
then the winch operator must “braille” for bottom by noting the slackening of the 
wire when the anchor touches bottom. A dynamometer for this purpose is useful, 
but a good winch operator can detect the reduced tension immediately. As there 
is a time lag for the bottom-detector signal to reach the surface, plus the operator’s 
personal reaction time, if the bottom-detecting device hits the bottom accidentally 
before the winch is slowed down, it is assumed that approximately 20 meters of 
the pilot line between the anchor and the bottom detector are lying on the bottom 
when the lowering stops. Thus, as soon as the winch is stopped, a meter reading 
of the amount of wire out is taken and then the winch operator hauls in 20 meters. 
A sounding is taken at this time and recorded. At this point, the bottom-detecting 
device is on the bottom with the anchor suspended on the mooring wire 150 feet 
above it. 
The special wire clamp is now secured to the standing part of the mooring wire, 
then the 10-foot wire-rope pennant from the subsurface float is shackled into the 
special clamp. The shackle is moused and the whole assembly coated with plumbers’ 
black mastic. The wire pennant and the nylon pennant leading to the skiff are all 
rigged outboard and clear. The weight is still on the mooring wire. 
On signal from the work platform, the winch operator lowers away slowly under 
power and the subsurface float is eased into the water by tag line. As soon as the 
float becomes water-borne, the load on the winch is greatly reduced. The winch 
operator continues to pay out until the anchor is on bottom, at which time it may 
be determined if the subsurface float is down to the proper depth. This may be 
roughly gauged by the 50-foot markers on the nylon pennant. In the event that 
