Figure L-15. 



Dynamometer attached to retractable 

 A-Frame. 



When using gravity corers without a release 

 mechanism, the corer should be lowered at the 

 maximmn payout rate of the winch; however, 

 as soon as an indication ( reduction in wire ten- 

 sion) is observed that the corer has reached the 

 bottom, stop the winch immediately to prevent 

 excessive wire being layed on the bottom. 



L-30 Applying Wax to Core Sample Lin- 

 ers. — An electrically heated vertical wax bath 

 (fig. L-16) is used by the U.S. Naval Oceano- 

 graphic Office for coating CAB (Cellulose Ace- 

 tate Butyrate) plastic seduuent core liners. The 

 vei-tical bath is constructed of copper sheet, and 

 its main cylinder has an inside diameter of 

 about 7 cm. The bath is approximately 130 cm. 

 high and holds about 3.6 kg. of wax. It is heated 

 by a sturdy flexible mantle approximately 180 

 cm. long by 6 cm. wide that operates on 110 

 volts a.c. Victory Brown-155 microcrystalline 

 wax is used. 



The operation of the wax bath aboard ship is 

 as follows : A liner is withdrawn from the core 

 barrel, capped, wijoed dry, labeled, and dipped 

 quickly into the bath. If the core liner is longer 

 than the wax bath and is not completely coated, 

 the remainder can be coated using a brush. Care 

 should be taken to heat the wax only a few de- 

 grees above its melting point of 68.33° C. as 

 excess heating changes the projierties of the 

 wax. 



As a field expedient when wax bath equip- 

 ment is not available aboard ship, CAB (Cellu- 

 lose Acetate Butyrate) plastic sediment core 

 liners can be wrapped with several layers of a 

 plastic wrap such as "Saran" Wrap to reduce 

 desiccation. 



Figure L-16. Applying wax to a plastic liner. 



L-31 Snapper or Grab Samplers. — Various 

 snapper or grab samplers are used to obtain 

 small samples of the superficial layers of the 

 ocean bottom. These samplers are excellent for 

 sampling surface sediments, but they do not 

 provide an undisturbed sample showing struc- 

 ture and microlayering. The sampling opera- 

 tions using snapper or grab bottom samplers 

 are recorded on Oceanographic Log Sheef>-M; 

 the samples are stored and shipped in sample 

 jars; and the samples are labeled with the Bot- 

 tom Sediment Label. The recording, labeling, 

 and shipping procedures are explained in para- 

 graphs L-39, L-40, and L-41. Examples of 

 these bottom samplers include the Orange Peel 

 bucket sampler, the Clamshell snapper, the Van 

 Veen bottom sampler, and the underway 

 Scoopfish. 



L-32 Orange Peel Bucket Sampler.— The 



Orange Peel bucket sampler is one of the grab 

 samplers used by the U.S. Naval Oceano- 

 graphic Office. It derives its name from its re- 

 semblance to the segments of a peeled orange 

 (fig. Lr-17) . The sampler weighs 45 pounds and 



L-14 



