e last new performer.
Thus, what is hailed as an original invention is often found to be but
the result of a long succession of trials and experiments gradually
following each other, which ought rather to be considered as a
continuous series of achievements of the human mind than as the
conquest of any single individual. It has sometimes taken centuries of
experience to ascertain the value of a single fact in its various
bearings. Like man himself, experience is feeble and apparently
purposeless in its infancy, but acquires maturity and strength with
age. Experience, however, is not limited to a lifetime, but is the
stored-up wealth and power of our race. Even amidst the death of
successive generations it is constantly advancing and accumulating,
exhibiting at the same time the weakness and the power, the littleness
and the greatness of our common humanity. And not only do we who live
succeed to the actual results of our predecessors' labours,--to their
works of learning and of art, their inventions and discoveries, their
tools and machines, their roads, bridges, canals, and railways,--but to
the inborn aptitudes of blood and brain which they bequeath to us, to
that "educability," so to speak, which has been won for us by the
labours of many generations, and forms our richest natural heritage.

The beginning of most inventions is very remote. The first idea, born
within some unknown brain, passes thence into others, and at last comes
forth complete, after a parturition, it may be, of centuries. One
starts the idea, another developes it, and so on progressively until at
last it is elaborated and worked out in practice; but the first not
less than the last is entitled to his share in the merit of the
invention, were it only possible to measure and apportion it duly.
Sometimes a great original mind strikes upon some new vein of hidden
power, and gives a powerful impulse to the inventive faculties of man,
which lasts through generations. More frequently, however, inventions
are not entirely new, but modifications of contrivances previously
known, though to a few, and not yet brought into practical use.
Glancing back over the history of mechanism, we occasionally see an
invention seemingly full born, when suddenly it drops out of sight, and
we hear no more of it for centuries. It is taken up de novo by some
inventor, stimulated by the needs of his time, and falling again upon
the track, he recovers the old footmarks