I.] ABVISABLENESS OF IMPROVING NATURAL KNOWLEDGE. 7 



It may not be too great a flight of imagination to 

 conceive our noble revenant not forgetful of the great 

 troubles of his own day, and anxious to know how often 

 London had been burned down since his time, and how 

 often the plague had carried off its thousands. He would 

 have to learn that, although London contains tenfold the 

 inflammable matter that it did in 1GG6 : though, not 

 content with filling our rooms with woodwork and light 

 draperies, we must needs lead inflammable and explosive 

 gases into every corner of our streets and houses, we 

 never allow even a street to burn down. And if he 

 asked how this had come about, w T e should have to 

 explain that the improvement of natural knowledge has 

 furnished us with dozens of machines for throwing water 

 upon fires, any one of which would have furnished the 

 ingenious Mr. Hooke, the first "curator and experi- 

 menter" of the Royal Society, with ample materials for 

 discourse before half a dozen meetings of that body ; 

 and that, to say truth, except for the progress of natural 

 knowledge, we should not have been able to make even 

 the tools by which these machines are constructed. 

 And, further, it would be necessary to add, that although 

 severe fires sometimes occur and inflict great damage, 

 the loss is very generally compensated by societies, the 

 operations of which have been rendered possible only 

 by the progress of natural knowledge in the direction of 

 mathematics, and the accumulation of wealth in virtue 

 of other natural knowledge. 



But the plague ? My Lord Brounckcr's observation 

 would not, I fear, lead him to think that Englishmen of 

 the nineteenth century are purer in life, or more fer- 

 vent in religious faith, than the generation which could 

 produce a Boyle, an Evelyn, and a Milton. He might 

 find the mud of society at the bottom, instead of at the 

 top, but I fear that the sum total would be as deserving 



