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 ...

JUST as “one shove of the bayonet” was truly said to be more effective than any number of learned discussions on the art of war:— this really practical work, giving genuine quaternion solutions of new ...

HAVING a vivid recollection of the pleasure I derived born Prof. Gibbs's attacks upon the quaternionic system in the rather one-sided discussion that took place about two years ago in this journal, I ...