establishment of fog signals on the coast of England. Indeed, his studies branched out toward the practical in a variety of directions; chief among them being his investigations concerning the nature of the dust particles in the air, and their relation to the germ theory of disease.
It is said that he had from youth a faculty of examining his premises with extreme minuteness, so that he was hardly ever known to proceed on a false assumption; and no theory ever propounded by him as the result of mature deliberation has been upset or seriously controverted. Another of his characteristics was that a research once entered upon, the work was carried on with the unflagging industry and persistence of an enthusiast. He has himself furnished the explanation of this in the following passage taken from his later writings:
My going to Germany had been opposed by some of my friends as quixotic, and my life there might perhaps not be unfairly thus described. I did not work for money; I was not even spurred by the "last infirmity of noble minds." I had been reading Fichte and Emerson and Carlyle, and had been infected by the spirit of these great men. The Alpha and Omega of their teaching was loyalty to duty. Higher knowledge and greater strength were within reach of the man who unflinchingly enacted his best insight. It was a noble doctrine. It held me to my work, and in the long, cold mornings of the German winter, defended by a Schlafrock lined with catskin, I usually felt a freshness and strength—a joy in mere living and working derived from perfect health—which was something different from the malady of self-righteousness.
Again he says of this German experience:
I risked this expenditure of time and money not because I had any definite prospect of material profit in view, but because I thought the cultivation of the intellect important—because, moreover, I loved my work and entertained the sure and certain hope that, armed with knowledge, one can successfully fight one's way through the world. And I must not omit one additional motive, which was a sense of duty. Every young man of high aims must, I think, have a spice of this principle within him. There are sure to be hours in his life when his outlook will be dark, his work difficult, and his intellectual future uncertain. Over such periods, when the stimulus of success is absent, he must be carried by his sense of duty.
But it was his power as a scientific expositor that gave Prof. Tyndall his worldwide reputation, and it is on this that his fame chiefly rests. His ability to present even abstruse subjects to a popular audience was unexcelled. The vividness of his imagination, which enabled him to form clear mental pictures of the phenomena he sought to explain, and his aptness in illustration led him to translate abstract ideas into their concrete equivalents.
On this point, the Athenæum remarks:
His lectures were not merely marked by logical reasoning expressed in forcible language, but they were models of method: nothing was left to chance;
