But the sentiments expressed at this dinner were echoes, only, of Tyndall’s thundering voice, to which America listened spellbound when he delivered the last of his course of six lectures on light. In the last part of this lecture, called “Summary and Conclusions,” he first erected what my mother would have called “a temple consecrated to the eternal truth” which we call light, and in that temple he placed what she would have called “the icons of the saints of the science” of light. The names of Alhazan, Vitellio, Roger Bacon, Kepler, Snellius, Newton, Thomas Young, Fresnel, Stokes, and Kirchhoff stood there like so many icons of saints which one sees on the altars of orthodox churches. In this he surpassed, I thought, even Maxwell and La Grange, and that was saying a great deal. He stood in the middle of that temple and challenged the statement once made by De Tocqueville that “the man of the North has not only experience but knowledge. He, however, does not care for science as a pleasure, and only embraces it with avidity when it leads to useful applications.” Tyndall proceeded to draw a clear distinction between science and its applications, pointing out that technical education without original investigations will “lose all force and growth, all power of reproduction,” just “as surely as a stream dwindles when the spring dies out.” “The original investigator,” said Tyndall, “constitutes the fountainhead of knowledge. It belongs to the teacher to give this knowledge the requisite form; an honorable and often difficult task. But it is a task which receives its final sanctification when the teacher himself honestly tries to add a rill to the great stream of scientific discovery. Indeed, it may be doubted whether the real life of science can be fully felt and communicated by the man who has not himself been taught by direct communion with nature. We may, it is true, have good and instructive lectures from men of ability, the whole of whose knowledge is second-hand, just as we may have good and instructive sermons from intellectually able and unregenerate men. But for that power of science which corresponds to what the Puritan fathers would call experimental religion in the heart, you must ascend to the original investigator.”