VIII. 



KNOWLEDGE AND OPINION. 



" What is the use," say many good people every 

 day in the present age, "of these new-fangied 

 modern scientific men ? No two of them ever 

 tell us the same thing twice ruiniing. One of 

 them advises us to eat nothing at all but bread 

 and vegetables ; another assures us we are eter- 

 nally and immutably constructed for a mixed diet 

 of beef and mutton. Doctor No. 1 declares that 

 cholera is due to a small creature, which he calls 

 by some terrific name or other, three times its 

 own length, a bacterium, or a microbe, or a bacil- 

 lus (as if he wanted to frighten us) ; Doctor 

 No. 2 informs us solemnlv that it is due to noth, 

 ing of the sort, but merely depends upon that 

 convenient medical Jack-of-all-trades, 'atmospheric 

 conditions.' Astronomer the first is profoundly 

 convinced that the spots in the sun are electric 

 storms on its disturbed surface ; astronomer the 

 second laughs him in the face because he ventures 

 to assert that the red sunsets we all so much 

 admire are ultimately dependent on the volcanic 



dust from the eruption of Krakatoa more than a 



90 



