genuine scientific man is, from the common point of view, almost always uneventful. Engrossed with the paramount claims of inquiries raised high above the domain of mere human passions, he is with difficulty tempted to come forward in political discussions even when they are of national importance, and he regards with surprise, if not with contempt, the petty municipal squabbles in which local notoriety is so eagerly sought. To him the discovery of a new law of nature, or even of a new experimental fact, or the invention of a novel mathematical method, no matter who has been the first to reach it, is an event of an order altogether different from, and higher than, those which are so profusely chronicled in the newspaper. It is something true and good forever, not a mere temporary outcome of craft or expediency. With few exceptions, such men pass through life unnoticed by, almost unknown to, the mass of even their educated countrymen. Yet it is they who, far more than any autocrats or statesmen, are really molding the history of the times to come. Man has been left entirely to himself in the struggle for creature comforts, as well as for the higher appliances which advance civilization; and it is to science, and not to so-called statecraft, that he must look for such things. Science can, and does, provide the means; statecraft can but more or less judiciously promote, regulate or forbid their use or abuse. One is the lavish and utterly unselfish furnisher of material good; the other the too often churlish and ignorant dispenser of it."
His next book was written in conjunction with Prof. Kelland, An Introduction to Quaternions, 1873. Kelland was the professor of mathematics, and it was his custom to expound to his senior class the elements of quaternions along with advanced algebra. Tait, so far as I know, never lectured on the subject at the University of Edinburgh. The volume in question grew out of Kelland's lectures, and was revised and supplemented by Tait. Kelland was much the older man, and had stood to Tait in the relation of instructor. In the preface, which was written by Kelland, light is thrown on the relation between the joint authors and colleagues: "The
