318 NATURAL SCIENCE. May, 



views of the ancients, beginning with the Phoenicians whose mercantile 

 expeditions were of such astonishing range, and the Greeks who first 

 directed attention to the scientific problems of the ocean, and of the 

 views entertained during the Dark Ages, the Middle Ages, and the 

 Renaissance ; next, with the progress of knowledge from Magellan to 

 Cook — from Cook to the " Challenger " and the subsequent expedi- 

 tions. This account, filling over a hundred of the familiar pages of 

 the " Challenger " Reports, is most clearly and attractively written. 

 It is illustrated with a series of coloured maps showing the progress 

 of our knowledge, the world-maps of the ancients being of particular 

 interest. I should greatly like to see this account made accessible to 

 many readers as a separate publication. From its simple and fasci- 

 nating style it would even make a school-book of the kind that com- 

 pels study. A school-boy, to my knowledge, broke off a bloodthirsty 

 tale for the attractions of this chapter accidentally discovered, and he 

 read it all. It is a triumph of the literary exposition of a subject 

 that might have been a dreary piece of pedantry. It is to be hoped 

 that Dr. Murray may be prevailed upon to adapt this wonderful 

 narrative to a wider circle than the readers of " Challenger " Reports. 

 If there were added to it a more extended account of the modern 

 voyages of research, it would make a book of the sea of the highest 

 educational effect on a maritime people. 



These great voyages of discovery did nothing for the deep-sea 

 until the middle of this century, and both biologists and geologists 

 have to thank telegraphic enterprise for the first impulse towards a 

 systematic exploration of the floor of the ocean. The desire to effect 

 telegraphic communication between Europe and America led to the 

 birth of the modern science of oceanography, which until then 

 reckoned only with the surface and imperfectly with circulation. 

 The apparatus of deep-sea work had to be invented, and with steady 

 progress in this invention very exact observations can be made, 

 though in all cases such observations are, from the nature of the case, 

 indirect. No better example is likely to be found of the influence of 

 progress in one science on progress in another than this exploration 

 of the ocean resulting from discoveries in telegraphy. Let it not be 

 forgotten, however, that telegraphy was only the opportunity. The 

 first self-registering thermometer was made about 1757 by Cavendish, 

 who suggested that it might be applied to ascertaining " the temper 

 of the sea at great depths." It was so applied by Irvine in 1773. 

 De Saussure and others continued such observations. Again, 

 specimens from the great depths were obtained by Sir John Ross in 

 his voyage to Baffin's Bay 181 7-1 8, and by his famous nephew, Sir 

 James Ross and Dr. (now Sir Joseph) Hooker on the Antarctic 

 voyage, who carried out remarkable deep-sea soundings. 



There follows next a general summary of the scientific observa- 

 tions and results at each of the " Challenger " observing-stations, 

 making, in fact, a scientific log of the voyage. This log, as we may 



