ctly coincides with one of the
lines representing a point of the compass.

The first master of the Young America worked the ruler down to a
diagram, and found that it coincided with the line indicating east by
north; or one point north of east.

"That's the course," said Thomas Ellis, the third master--"east by
north."

"I think not," added Foster. "If we steer that course, we should go
forty or fifty miles south of Cape Sable, and thus run much farther than
we need. What is the variation?"

"About twelve degrees west," replied Martyn.

The compass does not indicate the true north in all parts of the earth,
the needle varying in the North Atlantic Ocean from thirty degrees east
to nearly thirty degrees west. There is an imaginary line, extending in
a north-westerly direction, through a point in the vicinity of Cape
Lookout, called the magnetic meridian, on which there is no variation.
East of this line the needle varies to the westward; and west of the
line, to the eastward. These variations of the compass are marked on the
chart, in different latitudes and longitudes, though they need to be
occasionally corrected by observations, for they change slightly from
year to year.

"Variation of twelve degrees,"[1] repeated Foster, verifying the
statement by an examination of the chart. That is equal to about one
point, which, carried to the westward from east by north, will give the
course east-north-east.

[Footnote 1: These calculations are merely approximate, being intended
only to illustrate the principle.]

The process was repeated, and the same result being obtained, the first
master reported the course to Mr. Fluxion, who had made the calculation
himself, in the professors' cabin.

"Quartermaster, make the course east-north-east," said the first master,
when his work had been duly approved by the instructor.

"East-north-east, sir!" replied the quartermaster, who was conning the
wheel--that is, he was watching the compass, and seeing that the two
wheelmen kept the ship on her course.

There were two other compasses on deck, one on the quarter-deck, and
another forward of the mainmast which the officers on duty were required
frequently to consult, in order that any negligence in one place might
be discovered in another. The after cabin and the professors' cabin were
also provided with "tell-tales," which are inverted compasses, suspended
under the skylights, by which the officers and instructors below coul