40 



WORK OF THE CARNEGIE AND SUGGESTIONS FOR FUTURE SCIENTIFIC CRUISES 



a sounding, and used a considerable amount of our supply 

 of gasoline, it v/ill be apparent how greatly this simple 

 change helped us. 



Another advance in methods was the modification of 

 a Sigsbee reversing frame to contain two thermometers 

 instead of one. This frame was attached to the sounding 

 wire near the bottom snapper, and the original single 

 thermometer gave us only the temperature of the bottom 

 water. This information itself is of great interest to 

 oceanographers. We needed a check on the depth from 

 which the deposit was collected- -a check which would be 

 more reliable than that offered by the length of wire paid 

 out and the angle. Owing to the drift of the vessel and 

 crosscurrents in the deeps, the wire almost never dropped 

 in a straight line to the bottom. We were able to calculate 

 depths accurately from the difference between the readings 

 of two reversing thermometers sent down together. One 

 of them was protected against the enormous pressures at 

 great depths to give the true temperature; the other, being 

 unprotected, gave a reading which represented the tem- 

 perature plus the mechanical "squeezing" of the mercury 

 bulb due to the weight of the water column above it. 



Our echo-sounding device gave us a third check on 

 bottom depths, of course. In scientific work such as we 

 were doing, there are never too many checks. Even the 

 simplest procedure is subject to error at times; and our 

 aim was to attain the highest degree of accuracy possi- 

 ble in every measurement made on board. 



During heavy weather we often found our silk tow- 

 nets torn by a sudden surge of the vessel. These nets 

 were very expensive, and had to be made to order in 

 Washington. So we made every effort to save them. On 

 February 18, we tried attaching the nets to the ship by a 

 long rubber rope commonly used in the landing gear of 

 aircraft. Afterwards, we seldom lost a net. In addition, 

 after February 6, the plankton tows were made from the 

 forecastlehead, thus reducing the danger of fouling the 

 other wires which were lowered from the quarter-deck. 



The work with the pilot balloons was made very 

 successful by the beautiful blue skies we enjoyed after 

 clearing the dense clouds of the Peruvian coast. These 

 flights often lasted thirty to sixty minutes, so one can 

 imagine the severe strain on the muscles holding a heavy 

 sextant for that length of time. It was necessary to de- 

 vise some method for supporting the instrument. One of 

 the deck chairs was fitted with arms and uprights to 

 support an overhead bar. The instrument was suspended 

 from this by a long, thin coil spring. In this way the en- 

 tire weight was removed from the observer's arms; 

 while still allowing freedom of motion. The whole outfit 

 could easily be moved to whatever part of the deck was 

 most favorable for observing the balloon. Captain Ault 

 dubbed the device the "Joshua Chair," in honor of the 

 Old Testament hero who commanded the sun to stand 

 still. He had also suggested that it might better have 

 been named in honor of Moses who at one critical mo- 

 ment in history had to call in the assistance of two men 

 to support his arms. 



Captain Ault says: "With this device we perhaps 

 have carried the matter to an extreme, and caused the 

 balloon to stand still. On at least three occasions, the 

 balloon has suddenly appeared to be fixed in the sky, 

 moving only very slowly in altitude and azimuth. On the 

 first occasion, Torreson, the observer at the theodolite, 

 was observing the balloon for fifteen minutes without get- 

 getting much change. Finally Paul, who had been watch- 

 ing the flight, accused Captain Ault, the sextant man, of 



looking in the wrong direction and of reading altitudes 

 that were far too low. It turned out that the theodolite 

 had gotten sidetracked to Venus, and the difference be- 

 tween its altitudes of 76° and the altitudes by sextant of 

 45°, could no longer be ignored. On the second occasion 

 both observers got sidetracked to Venus." 



It is remarkable how closely a white balloon floating 

 at a great height resembles the planet in the sunshine of 

 the late morning or early afternoon. For most of us it 

 was a great surprise to know that Venus could be seen at 

 all in the middle of the day. Captain Ault told us that he 

 had occasionally used this planet for determining geo- 

 graphical position at sea. This trick appears to have 

 been known to mariners of former times, but has fallen 

 out of use. 



On February 8, Soule and Leyer moved the sonic 

 depth finder from the radio laboratory to the control 

 room on the quarter-deck. This was done to enable us 

 to take additional night soundings without disturbing 

 Jones who slept in the radio room. Paul had learned the 

 technique of using the apparatus and now took a sounding 

 after he had completed his Greenwich Mean Noon mete- 

 orological observations. Jones had by this time resumed 

 a large number of schedules with amateur radio stations 

 and had to get his sleep whenever he could, for he had 

 regular magnetic observations and computations to do in 

 the daytime. 



New equipment was brought on board at San Fran- 

 cisco. Mr. Gish had tested out a new Kolhorster pene- 

 trating radiation apparatus in Pasadena and with Park- 

 inson subjected it to further trials under the waters of 

 Crystal Lake near San Francisco. This instrument 

 registers the quantity of penetrating rays reaching the 

 earth and may be lov/ered into the sea to determine the 

 depth at which this powerful form of energy is absorbed. 

 Mr. Gish also supervised the installation of a photo- 

 graphic conductivity recorder which had just been de- 

 signed and constructed in our shop in Washington. 



Forbush had brought with him several new chro- 

 nometers and a photographic time-signal recorder with 

 which time comparisons could be made accurately to 

 one-tenth of a second and approximately to one -hundreth. 

 These delicate time checks were necessary for the 

 "gravity apparatus." He also brought new silk plank- 

 ton nets for capturing organisms floating in the sea. 



Graham had just come from the Scripps Institution 

 in La JoUa where he had spent a month in studying the 

 methods used in chemical oceanography. He and Dr. 

 Moberg spent most of their time in San Francisco in re- 

 conditioning the oceanographic laboratory and in pre- 

 paring new standard solutions. It was impossible to use 

 the delicate chemical balance on board so these men set 

 up the instrument on the pier. Graham also found time 

 to calibrate the bottles which were to be used in deter- 

 mining the amount of oxygen in sea water, "/e had had 

 such difficulty in obtaining distilled water of sufficient 

 purity for our chemical work that it was decided to buy 

 a small still of our own. Before Graham could take it 

 on board he had to sign five copies of an affidavit that it 

 would not be used for making liquor. 



The gravity apparatus which was installed in the 

 cabin by Dr. Wright was now to be tried out for the first 

 time on a surface vessel. Cruises in Dutch and Ameri- 

 can submarines had shown that it might be expected to 

 give reliable measurements if the roll of the ship did not 

 exceed 10°. Besides this we were not bothered with con- 

 stant vibration due to engines. The pendulum equipment 



