12 ABT. 3. SEIICHI KAWAMÜBA : 



for about two minutes and became invisible after two and a half 

 minutes more. Then the specimen was taken out into the external 

 air, in which it was seen to commence emitting light after thirty 

 seconds and to recover original light intensity after one minute. 

 A gill which was kept in the temperature of 50°C. for twenty 

 minutes never recovered its power of producing light. 



(h) 60°C. A gill in 60 C C. temperature began to show dimi- 

 nished light after thirty seconds ; after one minute only a feeble 

 light remained ; and after one minute and ten seconds, the light 

 was invisible. The specimen was then taken out into the air of 

 19.3 C C. Thereupon it became again luminous after fifteen seconds, 

 and completely recovered the original strength of luminosity after 

 thirty seconds. On the other hand, a gill taken out from the test- 

 tube fifteen minutes after it ceased to be luminous, did not emit 

 light again. 



(B) Experiments in water of various temperatures. 



My next attempt was to observe changes in luminosity in 

 water of various temperatures. Crushed ice or water of different 

 temperatures was put into a wide-mouthed bottle of 500 cc. capa- 

 city. Into this was thrown a piece of highly luminous gill, keep- 

 ing up a constant temperature during the experiments. 



(a) 0°C. In crushed ice the light began to decline in intensity 

 after five seconds and became invisible in half an hour. The gill 

 was then quickly taken out, whereupon after one minute it began 

 to emit a feeble light and recovered full luminosity in five 

 minutes. 



(b) 10.7°C. In the water of 10.7°C. the light became feeble 

 after ten minutes. As the water was stirred, the light temporarily 

 revived, to begin again to fade on being kept still for five seconds. 

 After half an hour from the beginning, the light was reduced, 

 roughly speaking to about one third of the original strength. 



