is often adduced by different writers as the most con- 

 vincing proof in favour of directly opposite views of the 

 histoiy of the world. These discrepancies are sufficient 

 to prove to any unprejudiced mind that the requisite 

 materials for constructing a perfectly natural system are 

 not yet accumulated, and that in every department of 

 Natural History patient observers are still required, 

 who will be contented to store up facts, and to work out 

 such parts of a general system as they find to be within 

 their legitimate reach, abstaining from all general views 

 that are not warranted by the amount, either of their 

 own knowledge, or of that of the scientific world in gene- 

 ral. Bold minds will now and then run a-head of abso- 

 lute discoveries, and by lucky anticipation will some- 

 times point in the right direction. Deeply informed and 

 comprehensive intellects will discover glimpses through 

 the haze, like the looming of distant land, where com- 

 mon observers can see no indications of a solution, and 

 their " guesses at truth," being built partly on real in- 

 duction, partly on skilfully-applied analogies, often open 

 up to us correct views of the order of Nature which sub- 

 sequent discoveries only confirm and strengthen. Such 

 minds will ever be cautious in advancing theories : but 

 how many hasty observers, admiring the brilliant re- 

 sults attained by the skilful " guesser," ignorant of the 

 liabilities to error, and therefore despising caution, rush 

 forward on their course, and propose to the world their 

 fanciful schemes as important discoveries. In the re- 

 public of science there is no longer a recognised head. 

 Each panter after fame may set up a system of his own. 

 There is no controlling power but the slow-working 



