MY remark about Prof. Willard Gibbs was meant in all courtesy, and I am happy to find it so taken by him. The question between us, being thus a scientific one only, can afford to wait for a fortnight ...

Imagine winding the hour hand of a clock back from 3 o’clock to noon. Mathematicians have long known how to describe this rotation as a simple multiplication: A number representing the initial ...

SINCE the publication of Hamilton's “Elements of Quaternions,” in which the great mathematician developed his new calculus with admirable skill and clearness, more than thirty years have passed away, ...