A PILOT'S NEEDS.

125

And how easily and comfortably the pilot's memory does its
work; how placidly effortless is its way; how unconsciously it lays
up its vast stores,
hour by hour, day
by day, and never
loses or mislays a
single valuable
package of them all!
Take an instance.
Let a leadsman cry,
* Half twain ! half
twain ! half twain !
half twain ! half
twain!' until it be-
come as monotonous
as the ticking of a
clock; let conversa-
tion be going on all
the time, and the
pilot be doing his
share of the talking,
and no longer con-
sciously listening to
the leadsman; and
in the midst of
this endless string
of half twains let
a single ' quarter
twain ! ' be inter-
jected, without
emphasis, and then
the half twain cry
go on again, just as
before: two or three
weeks later that pilot can describe with precision the boat's position in
the river when that quarter twain was uttered, and give you such a lot
of head-marks, stern-marks, and side-marks, to guide you, that you

1 LET A LEADSMAN CRY, " HALF TWAIN." '