Tlie Presidents'' Addresses. 20 



pen tine or petroleum, the cause of foliation, the stable or 

 unstable geographical relationships of continent to ocean, 

 the probable rate of geological time, the conditions of cli- 

 mate in the ages of maximum ice, the probable centres of 

 life-dispersion, the unity or multiplicity of the human race, 

 the evolution of species, be babbled over by men, the amount 

 of whose efficient work in any branch of science is measur- 

 able with a foot-rule ; while those, whose entire lives have 

 been but one exhausting struggle with the shapes which 

 people the darkness of science, speak with bated breath 

 and downcast eyes of these great mysteries ?" 



Young scientists test the value of old truths by new dis- 

 coveries, but veterans reverse the rule and try new discov- 

 eries by well-established principles. The progress of science 

 depends on the interaction of these mode of procedure. 

 " Not by the mere increment in number of facts learned, 

 not by the mere multiplication of discoverers, teachers and 

 students of those facts, but by the elevation of our aims, by 

 the enlargement of our views, by the refinement of our me- 

 thods, by the ennoblement of our personalities, and by these 

 alone can we rightly discover whether or not our Associa- 

 tion is fulfilling its destiny by advancing science in Am- 

 erica." 



Professor Lesley concluded bis address by insisting on the 

 absolute necessity for more " Dead-work" being done by the 

 true scientist. This department of science " comprises the 

 collection, collation, comparison and adjustment, the elimin- 

 ation, correction and re-selection, the calculation and re- 

 presentation — in a word, the entire, first, second, and third 

 handling of our data in any branch of human learning, — 

 wholby perfunctory, preparatory, and mechanical, wholly 

 tentative, experimental, and defensive, — without which it 

 is dangerous to proceed a single stage into reasoning on the 

 unknown, and futile to imagine that we can advance in 

 science ourselves, or assist in its advancement in the world." 



In regard to this, five propositions were laid down : " (1) 

 That without a large amount of this dead-work there can 

 be no discovery of what is rightly called a scientific truth. 

 (2) That without a large amount of dead-work on the part 



