272 THE POPULAR SCIENCE MONTHLY. 



which raised the temperature of the mind, though it refused to accept 

 shape, personal or otherwise, from the intellect. Perhaps the able 

 critics of the Saturday Review are justified in speaking as they some- 

 times do of Mr. Carlyle. They owe him nothing, and have a right to 

 announce the fact in their own way. I, on the other hand, owe him a 

 great deal, and am also in honor bound to acknowledge the debt. Few, 

 perhaps, who are privileged to come into contact with that illustrious 

 man have shown him a sturdier front than I have, or in discussing mod- 

 ern science have more frequently withstood him. But I could see that 

 his contention at bottom always was that the human soul has claims and 

 yearnings which physical science cannot satisfy. England to come will 

 assuredly thank him for his affirmation of the ethical and ideal side of 

 human nature. Be this as it may, at the period now reached in my 

 story, the feeling above referred to was indefinitely strengthened, my 

 whole life being at the same time rendered more earnest, resolute, and 

 laborious, by the writings of Carlyle. In this relation I cared little for 

 political theories or philosophic systems, but I cared a great deal for the 

 propagated life and strength of pure and powerful minds. At school 

 I had picked up some mathematics and physics ; my -stock of both was, 

 however, scanty, and I resolved to augment it. But it was really with 

 the view of learning whether mathematics and physics could help me 

 in other spheres, rather than with the desire of acquiring distinction in 

 either science, that I resolved, in 1848, to break the continuity of my 

 life, and to devote the meagre funds I had then collected to the study 

 of science in Germany. 



But science soon fascinated me on its own account ; and I could see 

 that, to carry it duly and honestly out, moral qualities were incessantly 

 invoked. There was no room allowed for insincerity — no room even 

 for carelessness. The edifice of science had been raised by men who 

 had unswervingly followed the truth as it is in Nature ; and in doing 

 so had often sacrificed interests which are usually potent in this world. 

 Among these rationalistic men of Germany conscientiousness in work 

 was as much insisted on as it could be among theologians. And why, 

 since they had not the rewards or penalties of the theologian to offer to 

 their disciples ? Because they asslimed, and were justified in assuming, 

 that those whom they addressed had that within them which would re- 

 spond to their appeal. If Germany should ever change for something- 

 less noble the simple earnestness and fidelity to duty which in those 

 days characterized her teachers, and through them her sons generally, 

 it will not be because of rationalism. Such a decadent Germany might 

 coexist with the most rampant rationalism without their standing to 

 each other in the relation of cause and effect. 



My first really laborious investigation landed me in a region which 

 harmonized with my speculative tastes. It was essentially an inquiry 

 in molecular physics, having reference to the curious, and then perplex- 

 ing, phenomena exhibited by crystals when freely suspended in the 



