656 FRAGMENTS OF SCIENCE. 



after describing the most distant of well-defined objects, 

 he should give utterance also to some of the subjective 

 impressions which he is conscious of receiving from regions 

 beyond; if he should depict possibilities which seem open- 

 ing to his view; if he should explain why he thinks this a 

 mere blind alley and that an open path; thenthe fault and 

 the loss would be alike ours if we refused to listen calmly, 

 and temperately to form our own judgment on what we 

 hear; then assuredly it is we who would be committing the 

 error of confounding matters of fact with matters of opin- 

 ion, if we failed to discriminate between the various ele- 

 ments contained in such a discourse, and assumed that 

 they had been all put on the same footing." 



While largely agreeing with him, I cannot quite accept 

 the setting in which Professor Virchow places the confess- 

 edly abortive attempts to secure an experimental basis for 

 the doctrine of spontaneous generation. It is not a doctrine 

 " so discredited " that some of the scientific thinkers of 

 England accept " as the basis of all their views of life/' 

 Their induction is by no means thus limited. They have 

 on their side more than the "reasonable probability" 

 deemed sufficient by Bishop Butler for practical guidance 

 in the gravest affairs that the members of the solar system 

 which are now discrete once formed a continuous mass; 

 that in the course of untold ages, during which the work of 

 condensation, through the waste of heat in space, went on, 

 the planets were detached; and that our present sun is the 

 residual nucleus of the flocculent or gaseous ball from 

 which the planets were successively separated. Life, as 

 we define it, was not possible for aeons subsequent to this 

 separation. When and how did it appear? I have already 

 pressed this question, but have received no answer.* If, 

 with Professor Knight, we regard the Bible account of the 

 introduction of life upon the earth as a poem, not as a 

 statement of fact, where are we to seek for guidance as to 

 the fact? There does not exist a barrier possessing the 

 strength of a cobweb to oppose to the hypothesis which 

 ascribes the appearance of life to that " potency of matter" 



*In the ''Apology for the Belfast Address," the question is rea- 

 soned out. 



