THE CRUISE 



39 



the plankton pump into operation. This apparatus is 

 lowered three times, to levels corresponding to the depth 

 of the townets. A measured volume of sea water passes 

 through a fine silk net. The number of organisms cap- 

 tured, divided by the number of liters of water pumped, 

 gives the "density of population" at each level. The 

 plankton nets are hauled in after an hour or so. The 

 specimens collected are preserved and labelled for fu- 

 ture study. 



It now remains to bring up the deep series and col- 

 lect the sediment from the bottom sampler. This done, 

 the sails are once more set and we proceed on our way. 

 If everything has gone well there is still an hour before 

 lunch in which to start the chemical work. The delicate 

 hydrogen-ion tests are made first, to avoid the possibil- 

 ity of changes in the samples from contamination by the 

 air or by sunlight. The other chemical characteristics 

 are determined after lunch, along with the salinity. 



These mornings are strenuous. There are many 

 operations going on at once. Wires lead in all directions 

 from the winch. The sun glares on the water, making it 

 necessary to wear dark glasses. And only careful co- 

 ordination saves us from utter confusion. Each man has 

 his appointed tasks, but is always ready to lend a hand 

 should things go wrong for the other fellow. And it was 

 a rare day when something did not go awry. Wires might 

 foul below the ship. Messengers might faU to reverse 

 the bottles; or a "jellyfish" get in the way. The piano 

 wire might snap, or the plankton pump fail to operate. 

 Anything might happen, without warning, to upset the 

 regular order. 



In Barbados we found ideal conditions for trying out 

 our diving helmet, and we made two expeditions to the 

 reefs. For several of the men it was an entirely new 

 experience. Only a poet could imagine the beauty and 

 romance to be found under the waters of a coral reef. 

 And certainly only a poet could describe what we saw in 

 this fairyland of color and form. The dinghy is anchored 

 at the selected spot, preferably in 15 to 30 feet of water, 

 and the observer climbs over the side with a heavy cop- 

 per helmet resting on his shoulders. A hose connected 

 to a hand pump in the boat keeps him comfortably sup- 

 plied with air, and he can wander alwut at will on the 

 bottom. 



One is in a new universe. Everything has a soft, 

 ethereal outline except for the fishes that come to within 

 an inch of the observers' nose to gaze at him in wonder 

 through the plate -glass window. They are the most bril- 

 liantly colored of living creatures. One's sense of per- 

 spective seems to have been lost. Put out your hand to 

 brace yourself on a coral head, and you find it far out of 

 reach. Walking itself seems ridiculous; for in the water 

 one's buoyancy is so great that the slightest spring up- 

 wards on the toes takes one off the bottom for a slow 

 easy flight through space. Gravity has ceased to exist. 

 Captain Ault described what he saw in a letter from 

 which the following words are taken: "... schools of 

 marvellously colored fish . . . forest of submarine trees 

 waving in the water-surges . . . baskets of shell . . . jewel- 

 cases of coral growth . . . grottoes of blue and sapphire . . 

 . .trees of growing coral with jewel tips . . .bristling, 

 black-spined sea-urchins ... a basket made of cocoanut- 

 palm leaves gathered together at the top, perhaps full of 

 treasure left by pirates ... a wonder-world not repro- 

 duced elsewhere, not even in an aquarium." 



Specimens were collected by the observers. A long 

 screw driver and a heavy brass bucket were lowered on 



a rope, and on a signal from below the material was 

 hauled up to the dinghy. Although the coral sand did not 

 promise to be very rich in diatoms, we secured several 

 bottles full for forwarding to Washington. 



In the Pacific, after October 1928, the weather 

 was perfect for pilot-balloon flights. The new equip- 

 ment, supplied by the United States Navy, worked well 

 and observations were made daily. With strong winds 

 we were able to follow the balloon for only fifteen to 

 twenty minutes, but sometimes it would be visible for an 

 hour. By tying two together we could often follow them 

 long after a single one would have been lost to view. In 

 this way we traced the direction and force of the wind in 

 the atmosphere up to heights of from two to six miles. 



Three men take part in a balloon flight- -usually 

 Captain Ault, Torreson, and Scott. A pure rubber bal- 

 loon is inflated with hydrogen from a tank, until it is 

 about three feet in diameter. By "weighing" it we are 

 able to calculate its rate of ascension. The scales oper- 

 ate upside down, of course, for the balloon pulls the pan 

 upwards. At a signal from Scott, the recorder, the glis- 

 tening globe is released. At one -minute intervals Tor- 

 reson reads the azimuth, or horizontal position of the 

 balloon with respect to the ship's heading; and Captain 

 Ault checks the altitude by using an ordinary sextant. It 

 was possible, of course, for Torreson to read off both 

 altitude and azimuth from his theodolite; but the rolling 

 of the ship often caused him to lose track of the object, 

 while it was still clearly visible to the sextant observer. 

 By reading the altitude from the sextant, it was possible 

 for Torreson to sweep the sky at that level until he had 

 again picked up the elusive sphere. 



As a result of a multitude of observations on wind 

 and weather conditions at sea, we have today fairly ac- 

 curate "pilot charts" of the ocean, for the use of mari- 

 ners. Now that transoceanic flying is coming to be a 

 serious enterprise and not merely a stunt, it is highly 

 important that aviators have "pUot charts" as well. 

 They must know the direction and velocity of the wind at 

 many levels, if they are to make successful flights over 

 the great expanse of the ocean. 



The month of February was a notable one for us in 

 that we made several important changes in our instru- 

 ments and methods. Ever since our departure from 

 Washington, an attempt had been made to use the marine 

 earth inductor for determining the strength of the earth's 

 magnetic field in addition to the angle of inclination. All 

 the trials up to the present time had failed to give re- 

 sults as reliable as those obtained with the standard "de- 

 flector." By changing the method slightly we now were 

 getting comparable readings. 



The Carnegie has ever been on the alert for new and 

 simpler methods for making physical measurements at 

 sea. In fact, her contributions in this respect may be 

 considered among the greatest of her achievements for 

 science, because little advance can be expected until re- 

 liable and practical instruments are available. 



In collecting samples of the ocean Ixattom we had 

 been using a "snapper" type of collector, in which a 

 large lead weight surrounding the shaft was made to 

 close the jaws when bottom was struck. It often hap- 

 pened, however, that the apparatus hit at an acute angle 

 and not head-on; in which case it would fail to close. By 

 countersinking the weight so as to bring it down over the 

 spring, the center of gravity was lowered. Thereafter, 

 only one failure was recorded from that cause. When it 

 is realized that it took from two to three hours to make 



