WYVILLE THOMSON 49 



cally sealed up a thick glass tube, wrapped it in flannel, and 

 enclosed it in a wide copper tube with perforated ends, and 

 then lowered the whole to a depth of 2,000 fathoms and 

 hauled it up, when it was found that the copper tube was 

 flattened by the pressure, and the glass tube inside the flannel 

 was reduced to a fine powder like snow. This process was 

 referred to by Sir Wyville Thomson as an " implosion," the 

 converse of an explosion. The most delicate animals, how- 

 ever, are able to exist under these enormous pressures, as 

 their tissues are permeated by fluids under the same pressure, 

 and are consequently supported equally on the inside and the 

 outside. It is only when some animal is brought up too 

 suddenly from a great depth to the surface that the release 

 of pressure has a disastrous effect. Some fishes arrive with 

 their eyes burst out of their heads, their scales forced off, and 

 other parts of the body horribly distorted. 



The temperature in these great depths is at or about 

 freezing-point ; and, as the sunlight probably only penetrates 

 for a few hundred fathoms, there must be total darkness with 

 the exception of occasional dim, ghostly glimmers of light 

 given out by phosphorescent animals. 



Moseley gives an amusing account of their tame and some- 

 what dilapidated parrot, who, from his perch on one of the 

 wardroom hat-pegs, talked away constantly and amused 

 them during the whole voyage. His great triumph, we are 

 told, was frequently to repeat : " What ! 2,000 fathoms and 

 no bottom ! Ah, Dr. Carpenter, F.R.S. ! " 



On the return of the expedition, Wyville Thomson was 

 appointed Director of the " Challenger " Expedition Commis- 

 sion, located in Edinburgh, for the purpose of seeing to the 

 distribution and investigation of the vast collections, and the 

 publication of the results ; and from that time onwards for 

 about twenty years Edinburgh was the centre of oceano- 

 graphic research and the Mecca towards which marine 

 biologists from all over the world turned to inspect the 

 novelties of the wonderful collections and to discuss results. 



