468 SPECIAL METHODS OF DISCOVERY. 



things, so in examining an unexplored scientific sub- 

 ject, we are certain to .discover new truths, if we properly 

 investigate. 



All geographical discoveries have been made by this 

 method. For instance, Columbus in 1492 crossed the 

 Atlantic and discovered America ; Vasco de Grama sailed 

 round the Cape of Good Hope, and discovered a new route 

 to India ; Cabral discovered Brazil ; Magellan discovered 

 Patagonia, the Straits which bear his name, the South 

 Pacific Ocean, and that our earth is a globe ; and in a 

 similar way others discovered Australia, New Zealand, and 

 many other parts of our world. The discoveries also made 

 by Carpenter, Wyville Thompson, and others, in the sub- 

 ject of deep sea dredging ; and by the numerous investi- 

 gators who have sounded the depths of the oceans, ascer- 

 tained their temperature, composition, currents, &c., in 

 different parts, may all be included under this heading. 



The discovery by Professor Boole, that the same laws 

 which govern algebra govern thought ; the invention of 

 Jevons's ' logical machine,' and the consequent discovery of 

 the possibility of drawing inferences by purely mechanical 

 means, arose from the study of a neglected department of 

 science. Other discoveries might probably be made in 

 the same direction. 



A difficulty in employing this method lies at the very 

 outset, and that is, to determine not so much what are 

 undeveloped parts of science for these lie in nearly all 

 directions but what undeveloped ones are likely to yield 

 important results, and what are sufficiently ripe. But as 

 the subjects of the relative importance and frequency of 

 different kinds of discoveries, and the selection of a suit- 

 able subject of research, have already been treated of in 

 Chapter? XIX., XX., and XXXVIII., I need not again 

 consider them here. Amongst the undeveloped or neg- 



