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Frautschy has described at this conference the details of the design of a 

 new, exceptionally promising winch which is being developed at the Scripps Insti- 

 tution. The importance of a fast, reliable winch cannot be overemphasized, for 

 on its reliable performance the success of the entire sampling program is de- 

 pendent. The winch should be relatively fast. Ships' time is extremely expen- 

 sive, and inexpensive slow winches can soon become very costly by viture of the 

 excessive time they consume. The day should soon come when a core can be 

 taken in any depth in an hour or less. Over 90% of the more than 600 deep sea 

 cores in the Lamont Geological Observatory collection were obtained during 

 short periods of spare time on cruises made for other purposes. Faster, more 

 reliable winches could have multiplied this figure. All oceanographers have ex- 

 perienced winch breakdowns or seen the wire part with valuable gear over the 

 side. Heavier better designed winches which take better care of the wire could 

 cut down the occurrence of such disasters. It is, conceivable that in the near 

 future heavier instruments such as heavier cores, heavy robot drilling rigs or 

 other weighty gear may be developed. It is therefore desirable that winches 

 using heavier tapered cable be developed; winches which would use heavier wire 

 than the presently used 3/8" to 3/4" sizes. 



In 1948 Professor Maurice Ewing and Mr. Angelo Ludas of Columbia 

 University modified a Hvorslev-Stetson free-fall corer to use tubes of greater 

 diameter (Zj" diameter) and to take a piston according to the principle described 

 by Kullenberg (1947). In subsequent years they have further improved and mod- 

 ified the instrument. Figure 1 is a drawing of this apparatus as constructed at 

 present. Figure 2 (modified Hvorslev, 1949) diagramnnatically shows its oper- 

 ation. From the experience of using the piston corer to obtain over 600 cores 

 (figure 3) in the North Atlantic it has been modified and improved until now it is 

 an efficient, convenient instrument. One of these improvements is the wire 

 clamp by which the tripping mechanism is attached to the main trawl wire. Be- 

 fore the addition of this clamp a serious problem was encountered in getting the 

 apparatus aboard after it was brought back from the ocean floor since the coring 

 head was hanging about 60 feet below the tripping device on a separate wire. 

 Now all that is necessary is to remove the clamp and winch in the wire. 



Telling when instruments are on bottom is extremely difficult and often 

 next to impossible. With the free-fall corer this problem is usually not serious. 

 As long as the core trips properly and the dynamometer is working, even in 

 very deep water an experienced man can have little doubt when contact is made. 

 A careful observer can observe the tripping of a free-fall core if the weight of the 

 the core equals or exceeds approximately 10% of the weight of the wire. Figure 

 4 is a reproduction of a tension vs. wire paid out plot of a type made on each 

 lowering on Lamont Geological Observatory cruises. A great advantage of the 

 free-fall core is the sharpness of the contact signal nnade by the momentary re- 

 lease of the entire weight of the core from the trawl which sends a jerk up the 

 wire. This principle might be employed in other gear such as dredges where 

 the release of the weight might serve no other purpose than to produce the con- 

 tact signal. The, length of the cores taken with the 1000-lb. rig (figure 3) varied 

 from chips of rock or a few inches of stiff clay to 50 feet in softer sediments. 

 Important advances may be made by taking longer cores. The fact that the pen- 

 etration of a 40-ft. coring tube driven by a 1000-lb. weight is often only a frac- 

 tion of the tube length indicates that a heavier weight is needed to increase pene- 

 tration. This requires heavier trawl wire and heavier winches since the winches 

 in use on most research vessels cannot handle appreciably greater loads. In 

 the localities where 40-50 foot cores have been taken (northern Gulf of Mexico, 

 upper continental rise off New England, the Azores plateau, etc.) it is likely 

 that cores may be taken up to and perhaps exceeding 100 feet with the present 

 1000-1500 lb. rigs. Indications are that these localities are ones of rapid sedi- 



