president's address. 25 



one stage, and that they prove nothing more than that precau- 

 tions which hitherto have been regarded as sufficient to destroy 

 the germs of such organisms are not so in reality. It may be 

 that we have got to the point at which we must admit some 

 modification in our views as to what constitutes a germ, and it 

 is even possible that germ functions are performed by bodies not 

 recognisable as such by the microscope. One eminent algologist, 

 Dr. Ferdinand Cohn, gives it as his opinion after many years of 

 patient research that sufficient is not yet known of the conditions 

 relating to the life of Bacteria to establish an argument in favour 

 of spontaneous generation upon it. 



Again it must be borne in mind, that in a case of this sort, 

 admitting the reasonableness of a germ theory, and therefore the 

 primary importance of precautionary measures, negative results 

 have at least an equal value with positive. If two observers, 

 working under the same general conditions, adopt precautions 

 agreed upon for the exclusion of sources of error, it is manifest 

 pari passu if their results be different, the one whose precautions 

 have succeeded is the more reliable. These and many others of 

 Dr. Bastian's processes have been repeated by trustworthy mani- 

 pulators with entirely negative conclusions. 



But, after all, if everything Dr. Bastian brings forward in his 

 two volumes were confirmed, he would still only be at the very 

 outset of an enquiry, upon the results of which the practical 

 value of these preliminary researches must depend. Standing as 

 they do his laborious observations are of comparatively little 

 value. Such things as he describes cannot come about without 

 Law. We have in his book no glimmering of explanation, not 

 even an attempt to construct a theory consistent with what he 

 regards as established facts. 



There is still a lingering and not unnatural distrust amongst 

 many thoughtful persons if studies such as those to which the 

 two works I have just noticed relate, and, admitting the unphi- 

 losophical excesses of some partisans on cither side, in the heat 

 of controversy, I am bound to say a word in defence of the studies 

 themselves. Truth has nothing to fear from science. Surely 

 the story of Galileo has still a lesson for us. His theory of the 



