Figure A-2. USNS Silas Bent ( AGS-26) Oceanographic survey ship. 



measuring instriunents, and numerous other 

 types of equipment ( fig. A-3) . 



One of the smallest winches is the hathy- 

 ther mo graph (BT) winch. This winch is used 

 to lower the BT, both while underway and when 

 lying-to on station. The winch carries 2,500 to 

 3,000 feet of %2-inch diameter stainless steel 

 wire. It is sometimes used in shallow water for 

 taking small bottom samples when underway 

 with a specially designed bottom sampler called 

 a "scoopfish.'' Mechanical current meters and 

 vertical hand plankton nets are sometimes 

 lowered from the BT winch. 



A special-purpose electri-cal. cable winch 

 equipped with 9,000 feet of 4-HO electrical 

 cable is carried on some survey ships. This 

 winch is used for lowering the transmitting 

 current metere and the sound velocimeter. 



The newer research ships with the Ship- 

 board Oceanographic Survey System aboard 

 also carry an intermediate loinch. This wincli 

 will hold 30,000 feet of 0.380-inch diameter 

 electrical cable in lieu of original i/o-^ich cable. 

 The Shipboard Survey System on-station fish 

 is operated from this winch. 



A-12 Laboratory and Storage Facilities.— 



An oceanographic sun-ey ship should have 

 laboratory, office, and storage spaces. A deck 

 laboratoiy is necessaiy in which instruments are 



A-4 



prepared for operation and some analyses are 

 carried out. It should be located near the ocean- 

 ographic winch. Other laboratory spaces are 

 needed where chemical, biological, and geologi- 

 cal analyses can be performed, where electronic 

 recording equipment can be installed, and where 

 photographic developing and printing can be 

 done. In addition to these laboratories, office 

 and drafting room space is needed to carry out 

 the reduction of data and preparation of pre- 

 liminary reports. Dry storage space for ocean- 

 ographic equipment and storage for samples 

 obtained during the cruise are a necessity. 

 Racks to stow cases of sea water samples, cases 

 of biological specimen jars, and core samples 

 also are required. 



A-13 Taking Oceanographic Observa- 

 tions. — Oceanographic observations are made 

 from a ship while underway, while lying-to on 

 station, and on occasion while the ship is an- 

 chored. An expedition for the collection of these 

 da-ta comprises an oceanographic cruise. Ob- 

 servations taken underway include bathyther- 

 mograph lowerings, occasional shallow water 

 bottom samplings, magnetometer tows, gravity 

 measurements, seismic profiles, current observa- 

 tions, plankton tows, pyrheliometer readings, 

 meteorologic observations, and sea and swell 

 observations. For special surveys, hull-mounted 

 recording devices are installed for obtaining 



