12 



WORK OF THE CARNEGIE AND SUGGESTIONS FOR FUTURE SCIENTIFIC CRUISES 



in the agreement between the overlapping temperatures 

 has since been noticed. 



Only on rare occasions does a deep-sea reversing 

 thermometer fail to function. Two or three of the un- 

 protected ones required replacement. The water bottles 

 all reversed and locked properly except on one occasion 

 when five of the shallow series were reversed too soon 

 for some unknown reason. 



The Pettersson plankton pump fails to operate 

 occasionally and must be sent down again. It was com- 

 pletely overhauled on February 19. Considerable pa- 

 tience is required to operate it and the ingenuity of Sei- 

 well and Leyer is being taxed to the utmost to keep it in 

 condition and to improve its operation. The results 

 should be an extremely valuable addition to the qualita- 

 tive as well as the quantitative data on plankton life and 

 distribution. 



During some of the ocean stations when the vessel 

 was rolling and pitching more than usual, the silk tow- 

 nets were torn by the quick jerking of the ship's motion. 

 Use then was made of the airplane rubber rope, the in- 

 board end of the towline being secured to a 20-foot 

 length of rubber rope to ease the strain on the towline 

 when the vessel surges. The rubber rope would increase 

 its length to twenty-eight feet at times. The nets have 

 not torn since using this device, but the seas have been 

 much smoother. 



The balloon work by Torreson, Scott, and Ault has 

 been unusually successful, owing to clear skies and mod- 

 erately smooth motion. Some thought has been given to 

 possible improvements to increase the efficiency of the 

 theodolite when it is to be used in stormy latitudes. The 

 use of the sextant for measuring altitudes increases the 

 time of following the balloon considerably, especially on 

 rough days. It permits the observer at the theodolite 

 (Torreson) to keep one hand on the counterweight below 

 to assist in keeping the instrument level, while the other 

 hand operates the horizontal-circle screw. If the bal- 

 loon is lost to the theodolite, the sextant gives its alti- 

 tude and Scott can give Torreson the approximate bear- 

 ing of the balloon by the direction of the sextant pointing. 



In view of the length of time one must hold up the 

 sextant and of the weight of the new balloon sextant, it 

 became necessary to devise some method for supporting 

 the instrument. One of the deck chairs was provided 

 with arms and two upright pieces supporting an overhead 

 bar. A coil spring was suspended from this bar, and the 

 sextant is now used hanging from this spring. The en- 

 tire weight is supported at the height of the observer's 

 eye and the freedom of motion is in no wise restricted. 

 The chair can be moved to the most advantageous posi- 

 tion on deck for observing the balloon; the use of the sex- 

 tant nov/ involves no strain on the observer's arms (fig. 

 30). 



On February 12, occasion was taken to have Parkin- 

 son secure pictures from the dinghy of the vessel under 

 sail, this time in the early morning with the sails full of 

 sunlight. Pictures were taken also after the vessel was 

 hove to for an ocean station. 



Soon after leaving the Peruvian coast the trade wind 

 was found to be more southerly than was expected, so we 

 could not at first follow exactly the route planned. Later 

 the part of the 1916 track from 112° west and 12° south 

 to 122° west and 17° south was followed exactly. At the 

 latter position it was decided to head west, directly for 

 Tahiti, through the Tuamotu Islands, instead of continu- 

 ing south around this group. This would increase the 



value of the oceanographic work, by giving a long cross 

 section almost due west from the coast of Peru to Tahiti, 

 and by giving additional data as to depths in the Tuamo- 

 tu group. Tatakoto Island was sighted early on March 7, 

 and on March 8 the vessel was hove to off Amanu Island 

 while the scientific staff made a visit ashore. About two 

 hundred and seventy people live on Amanu, chiefly en- 

 gaged in gathering copra. They appear healthy, happy, 

 and prosperous, and of a very high class of South Sea Is- 

 lander. There are no white people on the island. They 

 gave us a large number of coconuts, and when we re- 

 turned to the vessel in the afternoon, the chief and a 

 boatload of men and women accompanied us to see the 

 ship. 



The oscillator has given excellent service since re- 

 pairs at Callao, and a valuable series of soundings has 

 been taken by Soule, Jones, and Paul. On February 8 the 

 depth finder receiver was moved from the radio roomto 

 the control room, to decrease the crowded condition of 

 the radio room and to provide for an enlarged program 

 of depth finding, without disturbing the radio operator at 

 all times of the day and night. The change has worked 

 out well and has increased the comfort and efficiency all 

 around. On February 19, Soule, assisted by Leyer, com- 

 pletely overhauled the depth finder and substituted spare 

 parts for worn ones, At his request, Paul was instruct- 

 ed in the use of the depth finder in order to secure a 

 sounding in the early morning in connection with his 

 meteorological observations at Greenwich mean noon. 



On February 16, at 17h 19m ship's time, latitude 

 15fl south, longitude 98°3 west, the depth shoaled rapid- 

 ly from 5380 meters to 3403 meters, after which it again 

 deepened to 4530 at 17h 29m, when again there was a 

 gradual decrease to 4080 meters. The deep thus re- 

 vealed was named "Bauer Deep" in honor of Director 

 Louis A. Bauer. Throughout the cruise from Callao to 

 Papeete the bottom has been very irregular, as evidenced 

 also by the many echoes, as many as six surfaces being 

 indicated. 



While passing through the Tuamotu Group, many 

 soundings were taken in order to develop the bottom con- 

 tour in this region. Thirteen soundings were taken on 

 March 7, eleven on March 8, and nine on March 9, giving 

 a valuable contribution to our knowledge of the formation 

 in the vicinity of both Tatakoto and Amanu islands. A 

 new ridge, 2000 meters above the general contour was 

 discovered at 17° 40' south and 141° 37' west, between 

 Amanu and Hikueru islands. A few miles later, at the 

 ocean station, we had hard bottom, with a few fragments 

 of black lava, with no trace of ooze, showing the possi- 

 bility of fairly recent volcanic origin. 



Jones found unusually good radio conditions prevail- 

 ing after leaving Callao and was able to arrange frequent 

 schedules with amateurs in various parts of the United 

 States, Honolulu, Jamaica, and Panama. Later it became 

 necessary to communicate with the American Radio Re- 

 lay League station WIMK at Hartford, Connecticut, which 

 has been so continuously helpful on this cruise, through 

 two relays, namely, Yosemite, California (W6CIS) and 

 Fort Madison, Iowa (W9BCA). Thus it was possible to 

 keep the office fully informed of the daily progress and 

 of urgent needs. 



During the passage from Callao to Papeete, observa- 

 tions were obtained as follows: 63 declination measure- 

 ments, 17 inclination and horizontal-intensity stations; 

 3 and 1/2 eye-reading, 24-hour atmospheric-electric 

 series; 23 complete 24-hour potential gradient records; 



