Round about the Canary Islands the mean specific
gravity was fonnd to be 1 ‘02730 ; to tbe westward it
rises steadily until in longitude 28° W. it has reached
1-02762. Between longitude 28° W. and 54° W. the
mean specific gravity is 1-02773, the maximum hdng
1-02781. On approaching the M"est Indies it rapidly
falls off to an average of 1-02719 in the neighbourhood
of St. Thomas’s ; and if we take into account
all the observations made on the western side of the
Atlantic, from St. Thomas’s northward to the edge of
the cold water which separates the Cnlf-stream irom
the coast of Ameidca, we obtain the same average,
1-02719. Between Bermudas and the Azores an
almost perfectly uniform specific gravity was observed,
the mean heing 1-02713, and the extremes
1-02694 and 1-02727. As Madeira is approached the
specific gravity rises nntil it reaches 1-02746 close to
the island itself. The mean specific gravity on the
eastern side of the North Atlantic, between tbe
latitude of St. Tbomas’s and tbat of tbe Azores, is
1-02727, or slightly bigber than that of the water on
the Avestern side.
After leaving the Cape-Verde Islands, the ship s
course lay almost parallel to the African coast, and
at an average distance of about 200 miles from it.
Proceeding thus in a south-easterly direction, the
specific gravity fell rapidly from 1-02692 off St. lag o
on the 10th August, to 1-02632 on the 12th, after
which it retained the low mean specific gravity of
1-02627 until the 21st August, when the course Avas
changed to a Avesterly one along the equator. The
specific gravity of the Avater on this day Avas the
lowest hitherto registered for a surface-Avater; it Avas