surf beats as the waves generated and propagated from the storm centers, 
and intensive study being made of the prevailing meteorological conditions 
in this connection. 
Recently Unoki (74) published a very important paper on the fluctuations 
of sea level caused by the variation of atmospheric pressure. He derived 
that the bottom friction of sea water can be considered proportional to the 
velocity of the water near the bottom and applied this conclusion for ex- 
plaining the lag between the travelling pressure disturbances and resulting 
level fluctuations, the agreement between theory and observations being 
satisfactory. 
Internal Waves. As to the study of internal waves, we may mention Ichie's 
recent work. He examined theoretically the effect of bottom configuration 
upon the internal waves, assumption being made that the undulations of bottom 
are small compared to the depth of the water. 
Under Water Illuminations. The cay oceanographer engaged in marine 
optics in this country is Takenouti. He 76) made a series of measurements of 
underwater illuminations by the use of photronic cells and color filters, and 
explained the results theoretically. He was thus able to determine the 
diffusion ratio of underwater illuninations. 
Submarine Deposits. Tayama(77) pave a chart of the bottom deposits in 
the adjacent seas of Japan. Niino also made a great contribution to the 
submarine geology in the adjacent waters of Japan. 
Instruments. S. Watanabe is a very able thermometer maker in this 
country and has supplied thousands of reversing thermometers for home use up 
to the present. Last year the writer recommended his products to Dr. Sverdrup, 
Norway, to Dr. T. G. Thompson, Seattle, and to Dr. Revelle, of the Scripps 
Institution of Oceanography, La Jolla, California. Dr. Dale Leipper, of the 
Agricultural and Mechanical College of Texas, uses Watanabe's thermometers 
for the hydrographic survey of the Gulf of Mexico. Dr. Thompson is now re= 
questing an additional supply for his laboratories. 
In 1949, another Watanabe(79) constructed resistance thermometers for 
hydrographic use and discussed on the Joule effect which brings difficulty 
for using this instrument at sea. Kohei Ono, of the Hydrographic Office, 
Maritime Safety Agency, devised an electric current recorder which can be 
used suspended from an anchored buoy. This instrument will be the sole 
current recorder now in practical use in this country. 
Shizuo Ishiguro (80) is a very able hydrographic mechanician and de- 
vised many instruments. In 1949 he constructed an electrical recorder for 
sea wave pressure. Recently he constructed two types of wave recorders for 
Wind waves and swell and an apparatus for the stroboscopic analysis for 
preparing the wave spectrum. He also constructed an electric remote wave 
recorder in which the pressure element is used submerged on the bottom of the 
sea near the coast, 
