484 THE POPULAR SCIENCE MONTHLY. 



the luminous beam to be optically pure and therefore germless. 

 Having worked at the subject both by experiment and reflection, on 

 Friday evening, the 2lst of January, 1870, I brought it before the 

 members of the Royal Institution. Two or three months subse- 

 quently, for sufficient practical reasons, I ventured to direct public 

 attention to the subject in a letter to the Times. Such was my first 

 contact with this important question. 



This letter, I believe, gave occasion for the first public utterance 

 of Dr. Bastian in relation to this question. He did me the honor to 

 inform me, as others had informed Pasteur, that the subject " pertains 

 to the biologist and physician." He expressed " amazement " at my 

 reasoning, and warned me that before what I had done could be un- 

 done " much irreparable mischief might be occasioned." With far 

 less preliminary experience to guide and warn him, Dr. Bastian was 

 far bolder than Pouchet in his experiments, and far more adventurous 

 in his conclusions. With organic infusions he obtained the results of 

 his celebrated predecessor, but he did far more the atoms and mole- 

 cules of inorganic liquids passing under his manipulation into those 

 more "complex chemical compounds" which we dignify by calling 

 them " living organisms." ' For five years, or thereabouts, Dr. Bas- 

 tian ploughed the field without impediment from me, and, now that 

 one can overlook the work, I am bound in truth to say that very won- 

 derful ploughing it has been. As regards the public who take an 

 interest in such things, and apparently also as regards a large portion 

 of the medical profession, he certainly succeeded in restoring the 

 subject to a state of uncertainty similar to that which followed the 

 publication of Pouchet's A r olume in 1859. 



It is desirable that this uncertainty should be removed from the 

 public mind, and doubly desirable on practical grounds that it should 

 be removed from the minds of medical men. In the present article, 

 therefore, I propose discussing this question face to face with some 

 eminent and fair-minded member of the medical profession who, as 

 regards spontaneous generation, entertains views adverse to mine. 

 Such a one it would be easy to name ; but it is perhaps better to rest 

 in the impersonal. I shall therefore simply call my proposed co-in- 

 quirer my friend. With him at my side I shall endeavor, to the best 

 of my ability, so to conduct this discussion that he who runs may 

 read, and that he who reads may understand. 



Let us begin at the beginning. I ask my friend to step into the 

 laboratory of the Royal Institution, where I place before him a basin 

 of thin turnip-slices barely covered with distilled water kept at a 

 temperature of 120 Fahr. After digesting the turnip for four or 



1 " It is further held that bacteria or allied organisms are prone to be engendered as 

 correlative products, coming into existence in the several fermentations, just as inde- 

 pendently as other less complex chemical compounds." (Bastian, "Transactions of the 

 Pathological Society," vol. xxvi., p. 258.) 



