28, 
data from the testing; 
The velocity through brown, slightly muddy, fine quartz sand 
from a depth of 2840 fms, (5190 m.) was 5400 ft/sec, (1650 m/sec. ), 
One core section from 350 fms, (600 m,) contains green medium 
sand, slightly muddy, poorly sorted, with shells of foraminifera and 
other calcareous debris making up about half of the sediment, the remain- 
der and finer fraction being mostly quartz; through this type of sediment 
the velocity was 5300 ft/sec, (1615 m/sec.), 
The velocity through gray,rather muddy, poorly sorted, very 
fine sand, mostly quartz, was 5250 ft/sec. (1600 m/sec. ); the core was 
from a depth of 735 fms, (1435 m.). 
Through light chocolate brown lutite, very uniform, with a med- 
ian particle diameter of 1 1/2 microns from a depth of 2900 fms. (5310 m,) 
the velocity of sound was 4920 ft/sec. (1500 m/sec.). 
The last core section which was tested contained uniform dark 
gray lutite. This sediment has a larger calcium carbonate content and 
greater median particle diameter than the chocolate brown lutite (also 
called "red clay") mentioned above, The density of this core section was 
1,31, and water content: 57% by weight and 74, 8% by volume, The core 
was from a depth of 2610 fms, (4700 m.). The velocity of sound through 
this last tested core section was 4670 ft/sec, (1425 m/sec.) 
The frequency of the ultrasonic pulses was about 65, 000-200, 000 
cps. The accuracy of these preliminary measurements is about 5%, 
The data are important for the understanding of the transmission 
and reflection of sound, Perhaps these sound velocities are also typical 
