Leaders. 97 



systematic, and persistent experiment seldom invades in 

 vain. 



Nor do I think we should have to seek long to find 

 probable cause for these failures. In the first place, a 

 single experiment is nothing, since it is a mathematical 

 certainty that in a doubtful case the chances are very 

 many to one that but a negative result will be obtained. 

 Not that a negative result is by any means valueless, 

 since it narrows the field for investigation. The same 

 is true of two or three, or of a few experiments, partic- 

 ularly if conducted in a hap-hazard manner, or with little 

 reflection ; or in the endeavor to carry out an old proc- 

 ess, the essential details of which are ill understood or 

 unknown, and must be guessed at. 



This disposes of all the experiments I know of, my 

 own included, except those of Mr. Orvis described in 

 the article mentioned above, which, though inconclusive, 

 were of a much higher character. It would have been 

 an uncommon fluke of good fortune had success attend- 

 ed any of these experiments but his ; and, as to his, he 

 himself attributes his failure, not to impossibility, but to 

 adverse conditions inherent in his environment. 



Again, it is to be noticed that in every case within my 

 knowledge, Mr. Orvis's included, every one tried to fol- 

 low what they understood to be the Spanish process. 

 They all pickled their worms. Not one of them tried 

 the simple method which Dr. Garlick described in 

 his letters, printed on pages 88 and 94 of this book, as 

 that by which he succeeded. 



The Spanish process, as described, calls for the im- 

 mersion of the worms in " strong vinegar " (lire's " Dic- 

 tionary of Arts and Sciences"), "a strong mixture of 

 vinegar and water " (Imbrie). Other authorities use sub- 



