the paper, turned over and laid down again,--the so-called "method of
superposition," now generally regarded as quite allowable. Of course, a
figure can be treated in this way only in imagination and for this season,
probably, the method was not employed by Euclid. Its use, however, leads
always to true results, as anyone may see; and it was quite characteristic
of Professor Newcomb that he should have taken it up, not having the fear
of the Greek geometers before him.

Such was Newcomb; it will be long before American science sees his equal.
Mathematical genius is like an automobile,--it is looked upon in two
opposing fashions as one has it or has it not. A noted educator not long
ago announced his belief that the possession of a taste for mathematics is
an exact index of the general intellectual powers. Not much later, another
eminent teacher asserted that mathematical ability is an exotic,--that one
may, and often does, possess it who is in other respects practically an
imbecile. This is scarcely a subject in which a single illustration
decides, but surely Newcomb's career justifies the former opinion rather
than the latter; the amount and kind of his mental abilities along all
lines seemed to run parallel to his mathematical genius, to resemble it in
quantity and in kind.

The great volumes of astronomical tables without which no astronomer may
now venture upon a computation are his best monument; yet the general
reader will longer remember, perhaps, the lucid expositor, the genial
essayist, the writer of one of the most readable autobiographies of our
day.