Septembeb 25, 1908] 



SCIENCE 



399 



can not be done by every analyst, but we 

 must admit that every analyst is capable of 

 using an analytical method and also of 

 proving its value or the reverse: otherwise 

 he is not worthy the name of analyst. 



The great majority of analytical chem- 

 ists are not inventors of analytical meth- 

 ods, they are only users of them. Usually 

 when an analyst says: "I use a method of 

 my own," he means that he has perhaps 

 substituted a porcelain for a platinum 

 crucible or one form of burette for another 

 or altered the time of precipitation— in 

 other words, introduced an unimportant 

 variation into a standard method and 

 named it his own. And thus we have in 

 laboratories working in the same line a 

 host of modifications of standard methods, 

 which, while they do not necessarily cause 

 a great difference in analytical results, do 

 introduce a dangerous principle. And in 

 some cases the application of this principle, 

 that every analyst is privileged to modify 

 methods as he chooses, leads to absolutely 

 incorrect methods, as numerous cases which 

 might be cited prove. 



The remedy for this state of affairs is the 

 recognition of the principle that no chemist 

 is privileged to use any method or modifi- 

 cation of a method which has not the ap- 

 proval of a representative committee of his 

 brother chemists, authoritatively appointed 

 by a chemical society to investigate the 

 method. Further, that when a method is 

 adopted by such a committee, no deviation 

 from it should be allowable in the practise 

 of any individual. In short, we should 

 have standard methods of analysis and ad- 

 here to them. 



The argument against these ideas will be 

 that we do not want cook-book recipes in 

 place of general analytical methods. If 

 analytical chemistry is to be developed 

 in a scientific way it must be made to 

 yield absolute and not comparative results. 



There is much justice in these views. They 

 were the views I held for a number of 

 years. But it should be understood that 

 these principles in their application and 

 these general methods in hands less expert 

 than they should be, have brought down 

 upon the heads of chemists much indiscrim- 

 inate criticism. A merely practical or 

 business man does not have and can not be 

 expected to have any particular insight 

 into chemical methods, nor can he be ex- 

 pected to be able to judge of chemists. So 

 long as he deals with one chemist only, and 

 if this one happens to be a good analyst 

 and to have good jiidgment, his faith in 

 the profession may remain unchallenged. 

 But if, for the sake of checking results he 

 sends out ten identical samples to ten dif- 

 ferent chemists and receives ten reports of 

 varying degrees of disagreement, his faith 

 is likely to receive a shock. If he repeats 

 the experiment and fares no better and if 

 he finds that succeeding repetitions do not 

 bring reasonable agreement, he may come 

 to have in time nothing but cynical remarks 

 to make about chemists and the science of 

 chemistry. Of course the inaccurate and 

 inexperienced analyst is a factor in the 

 problem and must be considered, and while 

 other means must be devised to eliminate 

 this factor, as a practical necessity the 

 large chemical societies must take up con- 

 sistently and determinedly the problem of 

 the unification of methods of analysis. 

 The time has come when no analytical 

 method can be left to individual judgment. 

 Individual differences and individual pref- 

 erences must be abandoned in favor of the 

 greater good which will come from con- 

 certed action and unification in methods of 

 analysis. 



Something has already been done in the 

 line I have suggested. The Agricultural 

 Chemists, the Mechanical and Civil Engi- 

 neers, the Leather Chemists' Association, 



