ON IMPROVING NATURAL KNOWLEDGE 21 



our State are but the ripples and the bubbles upon the 

 surface of that great spiritual stream, the springs of 

 which only, he and his fellows were privileged to see; 

 and seeing, to recognise as that which it behoved them 

 above all things to keep pure and undefiled. 



It may not be too great a flight of imagination to 

 conceive our noble revenant riot forgetful of the great 

 troubles of his own day, and anxious to know how 

 often London had been burned dow*n since his time, 

 and how often the plague had carried off its thousands. 

 He would have to learn that, although London con- 

 tains tenfold the inflammable matter that it did in 

 1666; though, not content with filling our rooms with 

 woodwork and light draperies, we must needs lead in- 

 flammable 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, we should have to explain that the improve- 

 ment 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 experimenter" 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 opera- 

 tions of which have been rendered possible only by 

 the progress of natural knowledge in the direction of 

 mathematics, and the accumulation of wealth in vir- 

 tue of other natural knowledge. 



