66 



including some luminous substance. Jt was sometime, 

 indeed, before the existence of any foreign body could 

 be recognised : at length the shadow of an animal, in 

 rapid movement, appeared depicted on the bottom of 

 the basin, itself almost as transparent as the medium 

 in which it floated. The animal, when at rest, exhi- 

 bited a somewhat crescent form, and in swimming, 

 described a tortuous motion ; the verge or fringe 

 seemed to be that from whence the light was derived, 

 but of which the whole body occasionally partook, and 

 had every appearance of being a species of medusa. It 

 died a few minutes after we had received it, which was 

 attributed to the light of the candle rather than to 

 an increment of temperature in the medium. When 

 taken up on the point of a probe, it had the ap- 

 pearance and nearly the consistency of jelly : it 

 was diaphanous, and presented a spherical figure of 

 about one sixth of an inch in diameter. A further 

 quantity of sea water presented to us another, though 

 larger medusa, about three fourths of an inch in dia- 

 meter : it also died very shortly after we brought it 

 home ; and perhaps the light, as in the former case, 

 was the cause. Mr. Macartney observes, that the 

 medusa always retreats from the surface as soon as the 

 moon rises ; he also states that exposure to daylight 

 deprives them of the power of shining. 



By agitating the salt water containing a luminous 

 body occasional gleams were exhibited ; and being 

 transferred to a basin of fresh water, it sunk to the 

 bottom like a falling star. The effect here was of the 

 most beautiful description ; there appeared strings 

 of minute beads of fire, like a chain illuminated by 

 electricity. On stirring the fluid, these luminous points 

 were disentangled, and displayed a hemisphere of mimic 

 stars : the floating lights soon, however, ceased to illu- 



