old or it never could have occurred to one so little versed in
science as myself; and knowing that it is sometimes pleasanter to
meet the old under slightly changed conditions, than to go through
the formalities and uncertainties of making new acquaintance. At the
same time, I should say that whatever I have knowingly taken from any
one else, I have always acknowledged.

It is plain, therefore, that my book cannot be intended for the
perusal of scientific people; it is intended for the general public
only, with whom I believe myself to be in harmony, as knowing neither
much more nor much less than they do.

Taking then, the art of playing the piano as an example of the kind
of action we are in search of, we observe that a practised player
will perform very difficult pieces apparently without effort, often,
indeed, while thinking and talking of something quite other than his
music; yet he will play accurately and, possibly, with much
expression. If he has been playing a fugue, say in four parts, he
will have kept each part well distinct, in such a manner as to prove
that his mind was not prevented, by its other occupations, from
consciously or unconsciously following four distinct trains of
musical thought at the same time, nor from making his fingers act in
exactly the required manner as regards each note of each part.

It commonly happens that in the course of four or five minutes a
player may have struck four or five thousand notes. If we take into
consideration the rests, dotted notes, accidentals, variations of
time, &c., we shall find his attention must have been exercised on
many more occasions than when he was actually striking notes: so
that it may not be too much to say that the attention of a first-rate