478 SCIENCE PROGRESS 



bleaching. The experts for the prosecution concerned them- 

 selves with the effects of large amounts of nitrite ; the defence 

 was directed to flours as actually treated by a bleaching plant. 

 The judge found that commercially bleached flour cannot be 

 proved to be different from unbleached flour and that the result 

 of commercial bleaching was merely to alter the colour without 

 altering the nature, substance and quality of the flour so as to 

 render it a different article ! 



A remarkable aspect of the case was the attitude taken up by 

 some of the experts in deducing the behaviour of very small 

 quantities of a substance from what is known of the action of 

 large quantities. This method has been carried to exaggeration 

 by Dr. Wiley in America but that it is entirely fallacious few 

 scientific men will deny. In the first place, it ignores entirely 

 all possibility of selective action, such as is bound to occur when 

 an active agent is brought into contact with so complex a mixture 

 as flour ; secondly, scientific literature is full of well-authenti- 

 cated instances of the beneficial action of traces of substances 

 which in larger quantities act prejudicially ; much has been done 

 of late to put our knowledge of the mode of action of these small 

 quantities on a firm basis : it is therefore disconcerting to find 

 scientists of eminence adopting an attitude in the witness-box so 

 much at variance with proved fact as appears to have been the 

 case in the trial referred to. 



In view of the foregoing considerations, it is obvious that 

 there is grave danger in basing action affecting interests so 

 great as those of the milling trade on the partial opinions of 

 persons who necessarily have only a limited knowledge and 

 experience of the practical side of the question at issue. 



