TO DAVY JONES S LOCKER II9 



and the plate of bright red shrimps was dark as night: No 

 wonder I thought of the Kght as cool. 



On this and other dives I carefully studied the chang- 

 ing colors, both by direct observation and by means of 

 the spectroscope (Plate IV) . Just beneath the surface the 

 red diminished to one-half its normal width. At 20 feet 

 there was only a thread of red and at 50 the orange was 

 dominant. This in turn vanished at 150 feet. 300 feet 

 found the whole spectrum dimmed, the yellow almost 

 gone and the blue appreciably narrowed. At 350 I should 

 give as a rough summary of the spectrum fifty per cent 

 blue violet, twenty-five per cent green, and an equal 

 amount of colorless pale light. At 450 feet no blue re- 

 mained, only violet, and green too faint for naming. At 

 800 feet there was nothing visible but a narrow line of 

 pale grayish- white in the green-blue area, due of course to 

 the small amount of light reaching my eye. Yet when I 

 looked outside I saw only the deepest, blackest-blue imag- 

 inable. On every dive this unearthly color brought excite- 

 ment to our eyes and minds. 



A few familiar aurelia jellyfish drifted past while 

 we were sinking to 50 feet, and at 100 feet a cloud of 

 brown thimble jellies vibrated by the window. These were 

 identical with those which we had observed in vast swarms 

 in Haiti.^ They are supposed to be surface forms, but here 

 they were pushing against my window 20 fathoms down. 

 They were the first organisms which showed that the 



^ "Beneath Tropic Seas," Linuche jellies, pp. 20-23. 



