It was found adrift by a fishing vessel on 

 December 23, 1958, position 13°57' N., 99°07' 

 W., and returned to the Scripps Institution. 



Skiff #8 was moored without instruments on 

 November 9, 1958, in IZ2 fm. near the head of 

 the Gulf of Tehuantepec, position 15°43.6' N., 

 95°04.6' W. It was revisited and instrumented 

 on November 17. On November 27 it was again 

 visited and the instrumentation (malfunction- 

 ing) was removed. It was not found when sought 

 repeatedly during January and February 1959 

 (cruise TO-59-1) and remains unaccounted for. 



In each case (except skiff #8, about which 

 nothing is known) it was found that the painter 

 had parted. The investigators concluded, from 

 the condition of the painters and from other 

 circumstances (including experience with other 

 skiffs which had no thermistor strings and 

 were under better surveillance, and performed 

 much better), that some of the painters were 

 probably cut accidentally by passing vessels, 

 and some probably broken in bad weather after 

 having become entangled with the thermistor 

 strings. 



The longest series of recorded data was 

 an 1 1 -day series from skiff #21, and even 

 this was incomplete because the depth ele- 

 ment and bottom thermistor did not work. 

 Other series were likewise incomplete for 

 some channels of information, some for most 

 channels. This indicated failures in the in- 

 strumentation even before the skiffs went 

 adrift. 



Moored station type B (J. I). Isaacs, K. F. Holt, 

 G. B. Schick, and C. P. Jennings).- Simple home- 

 water mooring experiments were begun in 

 July 1959 to find ways to improve the parts 

 of the station assembly between the hull and 

 the subsurface float, i.e., the painter and 

 thermistor string. There are no grounds for 

 dissatisfaction with the previously used hull 

 or the taut-wire part of the mooring from 

 the anchor up to the subsurface float. 



The idea that seemed initially most attrac- 

 tive, and which has persisted in one form or 

 another up to the present, is that the upper 

 portion of the mooring should be a rubber 

 shock-absorbent cord that would be almost 

 vertical in the water in most kinds of weather 

 in which other craft would be likely to ap- 

 proach the skiff, and that this cord should 

 also support the thermistor string; we think 

 that in this way the causes of past failures 

 would be eliminated. The idea now is that 

 there should be a single extensible shock- 

 cord (Bungee) between the subsurface float and 

 the skiff and that the thermistor string should 

 be attached along it in a series of loops: an 

 additional advantage of this combination is 

 expected to be the maintenance of each ther- 

 mistor at a constant depth. The system is 



shown in diagrammatic form in fig- 

 ure 3. 



The first such mooring, made near the 

 Scripps Institution on April 8, 1960, failed when 

 the Bungee cord parted on May 30, Com- 

 mencing June 23, further series of similar 

 moorings were made with complete success, 

 which has continued, as mentioned above, 

 through December I960. 



During these tests the system was much 

 improved by the use of a modified subsurface 

 float, called the self-reeling subsurface float. 



The self-reeling subsurface float was con- 

 ceived to enable an instrument cable or a 

 mooring line, between a subsurface point of 

 attachment and a surface float, to be main- 

 tained free from slack with changing sea 

 conditions. This system also allows the cable 

 or wire to be retrieved and replaced without 

 disturbing the remainder of the mooring. The 

 self-reeling float consists of a spherical 

 buoyant tank which is modified by the addition 

 of three parallel reels having the same geo- 

 metrical axis of rotation. Two of these reels 

 are fixed to the sides of the sphere and a 

 larger reel is fixed about the center. The 

 ratio of the radii of these reels is designed 

 to give the desired balance of forces and cause 

 the float to wind itself up or down as the ten- 

 sion changes. When the tension on the surface 

 line exceeds a predetermined value, the float 

 winds itself down paying out a quantity of line. 

 If the tension in the center line is less than 

 a certain predetermined amount, the float will 

 wind itself up, reeling in the excess center 

 line. Its action may be compared to that of 

 a "yo-yo," and the float is now known by that 

 name. 



The relatively large extensibility of the 

 center line is affected mainly by the reeling 

 action of the subsurface float and to a much 

 smaller extent by the vertical motion of this 

 float. 



The two side reels wind and unwind two 

 stainless steel cables leading down to a 

 spreader bar and thence to the top of the 

 lower (taut-wire) part of the mooring, and 

 the center reel winds and unwinds a length 

 of nylon leading up to the lower end of the 

 shock-cord. The effect when used with Bungee 

 is to add to the extensibility of the upper 

 part of the mooring. The difference between 

 this system and the previously mentioned one 

 is shown diagrammatically in figure 3 (B3). 



A photographic method of recording has 

 been designed. The equipment consists of a 

 watertight and light-tight box containing a 

 camera, light source, timing motor, etc., 

 and a panel on which are mounted the various 



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