works through one channel only, that of comradery in research. We are Spudon Xynones—fellow pilgrims in a joyous land—full of glorious scenes, broad outlooks and repaying experiences. But the way we travel is beset with many difficulties both within and without. There are many temptations to turn aside from the main quest, from the large joys to the immediate successes, and the number of those who to the end remain Xynones is far less than the number who first strike out on the trail. These temptations are internal for the most part. The response to them depends on the man, not on anything outside of him. They are the intrinsic factors in his scientific evolution. But there are also extrinsic factors which undermine zeal and discourage enthusiasm. These extrinsic factors are sometimes potent, though relatively few, while the influence of the intrinsic factors decimates our band; wherefore we conclude that the individual in science is more than the environment. Men of research are born more often than made, but those well born may be spoiled or half-spoiled in the making. To prevent this, to keep the ranks firm, it is well for us to stand together, as comrades in zeal, and when necessary, as to-night, we may whistle bravely to keep up our courage.
And in standing together, it is well for men interested in one line of research not to look down on those whose taste or capacity favors some other. So long as it is real, research is the real thing, and one line may come as near the heart of things as another. Whence it is not good for the experimenter to look down on the systematist, the student of exact sciences on the mathematics of the imagination, the physicist on the psychologist, the chemist on the engineer, the engineer on the economist, the biologist who thinks in terms of chemistry only on the biologist who finds vital force a convenient temporary conception while searching for underlying causes, or any class on any other class, each being a loyal follower of the clue which has come into his hands. To be sure, not all is science which takes that name. 'Science falsely so called' is known to all of us as well as to the theologian. Of course, the name of science, even the name of research, is borrowed for purposes utterly at variance with science. Trade-marks which have a value are always imitated. With all that in the long run, there comes to be a science of non-science when even christian science and psychical research will ultimately find a place in the pigeon-holes of investigation.
In general, scientific research may be divided into four or five great classes.
Experiment.—The purpose of experiment is to test laws, to find out how things work. We arrange the conditions, nature does the rest, and our part of the process is to find out what the rest is. In the old days experiment was easy—to let fall an apple, to rub the hair of a cat, to bring a nail near a magnet. Nature would take advantage
