IXXX PROCEEDINGS. 



had deisgned it with loving care, and it was in my eyes pala- 

 tial. There I did my J5rst experimenting. As I recall the 

 equipment he had then been able to gather together after 

 about ten years of effort, it seems truly pitiful that such a 

 man should have had such lack of tools. You could put it 

 all in a good-sized wardrobe. Most of my work was dene 

 with a primitive lamp-and-scale galvanometer and Wheat- 

 stone's bridge and a Kohlrausch box of coils, with some 

 spools of wire, sealing wax, etc. I spent months rewinding 

 the galvanometer, resilvering its crippled mirror, and cali- 

 brating a stretched piece of German-silver wire to act as a 

 potentiometer. Then another three months weie given to 

 finding the inversion point of a thermo-couple. I must not for- 

 get formidable efforts which I made to rehabilitate an Atwood's 

 machine, whose warped supports, upright in name only, not 

 in morals, and cogwheels stained with verdigris, pathetically 

 called for rejuvenation. I got it so that it would go on 

 Saints' days, when one called out all his patience and 

 other virtues. This was MacGregor's laborator}', and yet 

 out of it came all that series of researches, as complete a list 

 of which as I could make in a hurry I have appended to this. 

 He had to cut his pattern therefore to suit his cloth; and had 

 to choose lines of research which could be done with a few 

 chemicals, glass tubing, a balance, a thermometer, and pluck, 

 determination and brains. Most of his work at this stage of 

 his career was in connection with the new ionization theory, 

 which he did much to advance from certain standpoints. He 

 always complained to me of the way he felt hampered by his 

 lack of a thorough grasp of mathematical physics; when I 

 came back from Johns Hopkins he would frequently tell me 

 how envious he was of the training I had received on that side 

 of physics. But I think he did himself an injustice, though 

 it is true he never trusted himself in that region of investiga- 

 tion or with that implement of attacking physical problems. 



