PRECESSION OF THE EQUINOXES. The slow backward motion of the equinoctial points along the ecliptic, at the rate of 50.1" annually, caused by the action of the sun, moon, and planets upon the protuberant matter about the earth's equator, in connection with its diurnal rotation; it is so called because either equinox, owing to its westerly motion, comes to the meridian sooner each day than the point it would have occupied without the motion of precession, and thus precedes that point continually.-Webster's Dictionary, 1892.

Our contemporary, the Daily Union, of September 7, 1893, in an article, on "When the Days and Night are Equal," makes a mistake in stating that "the equinoxes move westward, the movement amounting to nearly 1° a year." If so the complete circuit of the the heavens. would be accomplished in less then 360 year; whereas the great revolution takes place in something less than 26,000.

THE CATEGORIES. What are the categories, in the logical sense? WALDO E. LEWIS. The following is the statement of the categories given in Fleming's "Vocabulary of Philosophy," second edition, p. 73 :

The categories are the highest classes to which all the objects of knowledge can be reduced, and in which they can be arranged in subordination and system. Philosophy seek to know all things. But it is impossible to know all things individually. They are, therefore, arranged in classes, according to properties which are common to them. And when we know the definition of a class, we attain to a formal knowledge of all the individual objects of knowledge contained in that class. Every individual man we cannot know; but if we know the definition of man, we know the nature of man, of which every individual of the species participates; and in this sense we may be said to know all men. The attempt to render knowledge in some sense universal, has been made in all ages of philosophy, and has given rise to the categories which have appeared in various forms. They are to be found in the philosophy of Eastern nations, as a classification of things and ideas. The categories of the followers of Pythagoras have been preserved by Aristotle in the first book of his 'Metaphysics." Those, ascribed to Archytas are now regarded as apocryphal, and as having been fabricated about the beginning of the Christian era, to lower the reputation of Aristotle, whose categories are well known. They are ten in numbers, namely: substance, quantity, quality, relation, place, time, situation, possession, action, and suffer ing. The mnemonic lines which contain them, are these:

Arbor sex servos ardore refrigerat ustos

Cras rure stabo, sed tunicatus ero.