ye of the observer. The figures marked on the quadrant give the
latitude of the ship at the moment of meridian. The ship's time is
then made to correspond, that is to say, it must indicate 12 o'clock,
M., after which it is compared with the chronometer's Greenwich time,
and the difference enables the observer to determine the longitude. As
fifteen miles are allowed to the minute, there will be nine hundred
miles to the hour. The importance of absolute correctness in the
chronometer will at once be realized, since, were it only three
minutes out of the way, it would render the calculation as to
longitude wrong by nearly fifty miles, which might be, and doubtless
often has been, the cause of wrecking a ship upon rocks laid down upon
the charts, but supposed to be far away. With the chronometer and the
quadrant observation correctly ascertained, the sailing-master can
prick off his exact situation on the chart. So long as the weather
will permit a clear view of the sun at noon, the ship's precise
location on the wide waste of waters can be known; but when continuous
cloudy weather prevails, the ship's course is calculated by what is
called dead reckoning, depending upon the speed and distance run as
indicated by the log, which is cast hourly under such circumstances,
and becomes the main factor in calculating the position of the ship.
Of course the result cannot be very accurate, but is a dernier
ressort. When land is in sight no observation is necessary, as the
bearing of the ship is then unmistakably defined.

The sea was like molten sapphire as we glided swiftly along the
southern coast of Cuba, watching the gracefully undulating shore. The
mountains rose higher and higher, until they culminated in the lofty
peak of Pico Turquino (blue mountain), over ten thousand feet high, as
lately ascertained by actual measurement. There are coves and bays
along this coast where oysters _do_ grow upon trees, ridiculous as the
assertion first strikes the ear. The mangrove-trees extend their roots
from the shore into the sea, to which the oysters affix themselves,
growing and thriving until plucked by the fishermen. They are small
and of an inferior species compared with those of our own coast, but
are freely eaten in the island. Near the shore hereabouts are many
islets containing from three to five square miles, some of which are
quite barren, while others are delicious gardens, full of tropical
fruit trees, flowers, and odoriferous