Outboard from the oceanographic winch is a 

 platform, similar to tliat used for heaving a 

 leadman's chains. Over the platform is an A- 

 Frame or davit, from which is suspended a spe- 

 cial block called a meter wheel. This meter wheel 

 has a stainless steel sheave of an exactly meas- 

 ured circumference, which is connected by a spe- 

 cial cable to a counter block (fig. A-4). The 

 oceanographic wire is passed over the meter 

 wlieel sheave, and the amount of wire paid out 

 over the side is indicated by the counter dials. 

 A lead weight of about 100 pounds then is at- 

 tached to the end of the wire. This is lowered 

 over the side, outboard of the platform, after 



the ship is dead in the water. Water sampling 

 bottles, usually of the Nansen type, equipped 

 with deep-sea reversing thermometers, are at- 

 tached to the wire at predetermined intervals 

 as the wire is lowered into the water. After the 

 Nansen bottle cast (or casts) has been com- 

 pleted, the oceanographic winch may be used to 

 lower other samphng devices such as the bottom 

 sediment corer, underwater camera, or plankton 

 nets. 



The time involved in taking a series of ob- 

 servations as described above, in water 4,000 to 

 5,000 meters deep, would be approximately 7 

 liours. If a large coring device, such as the half- 



C 



Figure A-4. Platform, A-Prame, meter wheel, and counter block. 



A-6 



