I 



ADDKESS. O 



a very large share of the work of advancing Science, and is fully entitled 

 to be periodically represented in the Presidency of the whole Association. 



I trust also I shall prove to you that applications of Science, and 

 discoveries in pure Science, act and re-act the one upon the other. 

 I hope in this to carry the bulk of my audience with me, although there 

 are some, I know, whose feelings, from a false notion of respect for 

 Science, would probably find vent in the ' toast ' which one has heard in 

 another place — this ' toast ' being attributed to the Pui-e Scientist — 

 ' Here's to the latest scientific discovery : may it never do any good to 

 anybody ! ' 



To give an early illustration of this action and re-action, which I con- 

 tend occurs : take the well-worn story of Galileo, Torricelli, and the pump- 

 maker. It is recorded that Galileo first, and his pupil Torricelli afterwards, 

 were led to investigate the question of atmospheric pressure, by observing 

 the failure of a pump to raise water by ' suction,' above a certain level. 

 Perhaps you will say the pump-maker was not applying science, but was 

 working without science. I answer, he was unknowingly applying it, and 

 it was from that which arose in this unconscious application that the mind 

 of the Pure Scientist was led to investigate the subject, and thereupon to 

 discover the primary fact, of the pressure of the atmosphere, and the 

 subsidiary facts which attend thereon. It may appear to many of you 

 that the question of the exercise of pressure by the atmosphere should 

 have been so very obvious, that but little merit ought to have accrued to the 

 discoverer ; and that the statement, once made, must have been accepted 

 almost as a mere truism. This was, however, by no means the case. 

 Sir Kenelm Digby, in his ' Treatise on the Nature of Bodies,' printed 

 in 1658, disputes the proposition altogether, and says, in effect, he is 

 quite sure, the failure of the pump to raise water was due to imperfect 

 workmanship of some kind or description, and had nothing to do with 

 the pressure of the air ; and that there is no reason why a pump should 

 not suck up water to any height. He cites the boy's sucker, which, when 

 applied to a smooth stone, will lift it, and he says the reason why the 

 stone follows the sucker is this. Each body must have some other body 

 in contact with it. Now, the stone being in contact with the sucker, 

 there is no reason why that contact should be broken up, for the mere 

 purpose of substituting the contact of another body, such as the air. It 

 seems pretty clear, therefore, that even to an acute and well- trained 

 mind, such as that of Sir Kenelm Digby, it was by no means a truism, 

 and to be forthwith accepted when once stated, that the rise of water on 

 the ' suction side ' of a pump was due to atmospheric pressure. T hardly 

 need point out that the pump-maker should have been a member of ' G.' 

 Galileo and Torricelli, led to reflect by what they saw, should have been 

 members of ' A ' of the then ' Association for the Advancement of 

 Science.' 



But, passing away from the question of the value of the application 



