246 



SCIENCE-GOSSIP, 



[Nov. 1, 1865. 



Popular Science Review^ where I knew there was an 

 article by the celebrated naturalist, De Quatrefages, 

 on this very subject. The article is far too long for 

 reproduction in Science Gossip; but some of the 

 readers may perhaps feel interested in knowing that 

 M. De Quatrefage's experiments tend to show that 

 the luminous appearance is owing to the presence of 

 living creatures, called Noctilucce. Many theories 

 seem to have obtained credence from time to time. 

 The article in question says, "Ancient navigators 

 appear to have attributed the light which is developed 

 on the surface of the water to what may be termed 

 ' ordinary causes,' and they believed it to be due to 

 various atmospheric phenomena. To them phos- 

 phorescence was the meteor of the sea. Abbe Nollet 

 sees in it nothing more than a modification of elec- 

 trical phenomena. Bujon refers it to a disengage- 

 ment of electricity. Tingry compares it to the 

 fluorescence of the diamond,, and thinks that the sea 

 absorbs solar light during the day, which is liberated 

 at night. It has also been attributed to ' phosphoric 

 fires,' and to the ignition of bubbles of hydrogen 

 bursting at the surface of the water, &c., &c. As 

 far back, however, as 1705, Professor Viviam, of 

 Genoa, discovered fourteen species of luminous 

 animalculse. To their presence he attributed the 

 phosphorescence of the seas of his country. In our 

 day everything tends to prove that the sea possesses 

 its phosphorescent fauna, as does the land." 

 Some of M. De Quaterfages' experiments were 

 very striking. He says, " 1 took some water from a 

 very brilliant wave, and with it filled a tube one 

 decimetre (about four inches) in height. After it 

 had been permitted to stand a few minutes, the 

 layer formed by the aggregation of Noctiluae was 





V 



one and a half centimetres in thickness; conse- 

 (lueutly, the auimalculse constituled a seventh of the 

 whole mass of fluid," He also says, "1 have 

 subjected luminous water to filtration (a rather fine 

 handkerchief suffices for the experiment). The 

 Koctilucte remained in the linen, to which they 

 ijiiparted a brilliant light, whilst, on the other hand, 

 the filtered liquid presented no signs of phos- 

 phorescence, notwithstanding every means employed 



to promote it," Some of our readers may, perhaps, 

 be interested in his description of the animal. He 

 says, " The Noctilucce are microscopical animalculae, 

 bearing a pretty general resemblance to little melons 

 deeply indented at one end. Near this depression 

 is fixed an appendage, which the animalcule moves 

 slowly to and fro, swaying from right to left. The 

 body is so completely transparent as to admit of its 

 structure being studied in its minutest details. Near 

 the appendage these membranes present a minute 

 orifice, which serves as the outlet for a little mass of 

 pellucid, homogeneous, and finely granulated sub- 

 stance, which is prolonged into the internal part of 

 the body. Prom the mass which forms, as it were, 

 a centre, there radiate in every direction a number 

 of extensions, which become more and more ramified 

 as they proceed, and of which the ultimate in- 

 definitely multiplied ramifications spread themselves 

 over the wliole inner surface of the animal." M. De 

 Quatrefages then describes the animal very minutely, 

 and adds, "Examined by a power of twenty or 

 thirty diameters, the illuminated portion of the body 

 of the Noctiluc(B presents a uniformly bright aspect. 

 With sixty diameters, a number of small but 

 brilliant scintillations become visible, detaching 

 themselves, as it were, from parts of what appears 

 to be a pale luminous background, and these scin- 

 tillations come and go with the rapidity of lightning. 

 An enlargement of one hundred and fifty diameters, 

 however, reveals the true character of the phe- 

 nomenon. It then becomes obvious that the light 

 emitted from the whole body, or any of its parts, 

 is composed of a vast number of instantaneous 

 scintillations, closely approximating to one another 

 at the centre of the "phosphorescent" portions 

 but disseminated and clearly distinguishable at the 

 edges. Occasionally there may be seen isolated 

 sparks at the extreme limit of the luminous part, or 

 even beyond it. Those of our readers who care to 

 go fui-ther into this subject will do well to consult 

 M, Quatrefages' article. 



BROMLEY : AND WHAT I EOUND 

 THERE. 



"11/1" ANY and many a visit has the writer paid to 

 -LvX this pretty neighbourhood, and very many 

 have been the microscopical treasures there found. 



One day last summer, being unable to get a com- 

 panion, he set out alone, resolved to make the best 

 of circumstances, such as they were. No sooner 

 had the train started than it began to rain, and it 

 continued raining, sometimes heavily, during the 

 rest of the day ; being provided, however, with a 

 waterproof cape, the inconvenience was not great. 



Diptera, &c., being scai'ce in such weather, there 

 was no alternative but to search the horseponds and 

 ditches in the vicinity of the path, iu the hope of 

 obtaining aquatic larvae. 



