THE CONQUEST OF NATURE 



OTHER INDUSTRIAL PROBLEMS OF TO-DAY AND 

 TO-MORROW 



In attempting to suggest the importance of science 

 in its relation to modern industries, I have thought it 

 better to cite three or four illustrative cases in some 

 detail rather than to attempt a comprehensive summary 

 of the almost numberless lines of commercial activity 

 that have a similar origin and ^ dependence. 



To attempt a full list of these would be virtually 

 to give a catalogue of mechanical industries. It may 

 be well, however, to point out a few familiar instances, 

 in order to emphasize the economic importance of 

 the subject; and to suggest a few of the lines along 

 which present-day investigators are seeking further 

 conquests. 



Very briefly, then, consider how the application of 

 scientific knowledge has changed the aspect of the 

 productive industries. Thanks to science, farming is 

 no longer a haphazard trade. The up-to-date farmer 

 knows the chemical constitution of the soil ; understands 

 what constituents are needed by particular crops and 

 what fertilizing methods to employ to keep his land 

 from deteriorating. He knows how to select good seed 

 according to the teaching of heredity; how to combat 

 fungoid and insect pests by chemical means; how to 

 meet the encroachments of the army of weeds. In 

 the orchard, he can tell by the appearance of leaf and 

 bark whether the soil needs more of nitrogen, of pot- 

 ash, or of humus; he uses sprays as a surgeon uses 



