WORK. I2 - 



book, in which it turned out to be inaccurately given. He 

 had a chemical balance which dated from the days when he 

 worked at chemistry with his brother Erasmus. Measure- 

 ments of capacity were made with an apothecary's measuring 

 glass : I remember well its rough look and bad graduation, 

 With this, too, I remember the great care he took in getting 

 the fluid-line on to the graduation. I do not mean by this 

 account of his instruments that any of his experiments suffered 

 from want of accuracy in measurement, I give them as exam- 

 ples of his simple methods and faith in others faith at 

 least in instrument-makers, whose whole trade was a mystery 

 to him. 



A few of his mental characteristics, bearing especially on 

 his mode of working, occur to me. There was one quality of 

 mind which seemed to be of special and extreme advantage 

 in leading him to make discoveries. It was the power of never 

 letting exceptions pass unnoticed. Everybody notices a fact 

 as an exception when it is striking or frequent, but he had a 

 special instinct for arresting an exception. A point appar- 

 ently slight and unconnected with his present work is passed 

 over by many a man almost unconsciously with some half- 

 considered explanation, which is in fact no explanation. It 

 was just these things that he seized on to make a start from. 

 In a certain sense there is nothing special in this procedure, 

 many discoveries being made by means of it. I only mention 

 it because, as I watched him at work, the value of this 

 power to an experimenter was so strongly impressed upon 

 me. 



Another quality which was shown in his experimental 

 works was his power of sticking to a subject ; he used almost 

 to apologise for his patience, saying that he could not bear to 

 be beaten, as if this were rather a sign of weakness on his 

 part. He often quoted the saying, " It's dogged as does it ; " 

 and I think doggedness expresses his frame of mind almost 

 better than perseverance. Perseverance seems hardly to ex- 

 press his almost fierce desire to force the truth to reveal itself. 

 He often said that it was important that a man should know 



