Savannah morning news. [volume] (Savannah) 1868-1887, 1885-04-28
THE SOLAR ECLIPSE OF 1886.
Papers Read Before the Washington
Academy of Sciences.

From the Esqo York Tribune.
WASHINGTON, April 24.-The first pa
per read before the National Academy TO-
day was by Prof, E. D. Cope, on "Phylo-
geny of the Placental Mammalia." 1t
was intended to express Prof. Cope's
views as to the genetic conditions of the
orders of placental mammalia and the pc
Rod Of divergence. Some Of these he
showed to have been specialized att much
earlier period than has been generally
supposed. The paper was discussed by
Messrs. Gill and Morse, Mr.. Morse ex-
pressing great admiration and Mr.. Gill
criticising and slightly dissenting from
the conclusions reached. Mr.. Gill felt
quite certain that man was derived from
genus Of apes a good deal like the
gorilla, the point of divergence being the
early part of the miocene period.
Mr.. Skinner offered some suggestions as
to the best manner Of observing the solar
eclipse Of Aug. IS, 1886. The shadow
starts from the West India Islands. passes
easterly by the coast of South America
to the coast of Guinea in Africa. On
leaving the West Indies the duration of
the shadow would he minues - seconds,
and in mid-Ocean minutes 30 seconds.
Over much of the track there are no pos
sible points Of observation, but where the
shadow strikes the African shore it is
11G miles broad. 1t would be unwise and
expensive to seek a location in the inte-
riOr, as all burdens must be carried on
the backs of men. On the coast there is a
good harbor miles broad. There is,
however, no fresh water. Staying there
long enough to secure results would prGba
ably involve the risk of African fever.
Prof. Young, Of Princeton, asked at what
season this eclipse would occur, and Mr.
Skinner replied that it was at the close of
the dry season, generally supposed to be
the most healthy.
Prof. Remsen read an interesting paper
on the "Chemical Action in a Magnetic
Fluid" Metal carefully adjusted being
placed within coils, the action and dsso-
luton of the metal was found to be con-
siderably retarded. A less marked re-
tardation was found when an electro
magnet was Ised instead of coil.
A. Graham Bell read a paper on the
measurement of Hearing Power" At
a recent convention of "articulate''
teachers in New York the startling state
ment was made that 10 per cent. of the
pupils in the State Deaf and Dumb Insti-
tuition could be taught to speak by the
use of the speaking tube, while the re-
ports of DR.. Sexton in regard to the pub
lie school children of the city Of New
York show that 10 per cent. of
the children are sufficiently deaf to
need TO be placed in front benches.
with the best ear toward the teacher,
while per cent. need a special
institution. Proper arrangements for
such children cannot be made until hear
ing can be measured, and Prof. Bell was
appointed one of a committee to find a
way. He showed the telephone instru-
ment used, where the child himself is
taught to distinguish the point at which
hearing stops as he increases the distance
between the primary and secondary coils.
He had made an examination of 727 cases
in the Franklin school of Washington
city. The audiOmeter registered the
hearing of the best ear. There was an
immense difference between the two ears.
In deaf and dumb asylums
there are pupils who hear better than the
worst cases in the public schools. In the
schools there are children who need the
specialized teaching of the asylum. There
is no broad line OF demarkatiOn between
the deaf and the hearing children.
They shade into each other. Many chill
dren are thought to be very stupid at
school only because they do not hear, and
need only change of seat, while in the
asylum are many who should be called
hard Of hearing speaking children instead
Of deatmutes.
An interesting paper was presented by
Prof. Gill and Mr.. Ryder on the ''Evolu-
ton and HomOlogies of the Flukes of
Cetaceans and Sirenians." A. Graham
Bell followed Mr.. Ryder with an account
of the experiments of Mr.. Frank De La
Tore, in Baltimore, il obtaining echoes
from the ships in the harbOr by means of
a new kind of fog signal, which would
make it possible to discover a ship in a
fog at half a mile distance. Prof. Bell had
recently been in Baltimore, where the ex-
periments had been made to the sat
isfactiOn of Prof. Rowland and himself.
A speaking-tube was attached to a gun.
Blank cartridges were fred and distinct
echo obtained at the distance of a mile. A
small tug gave the echo at a quarter of
mile. One source of error might be found
in low thunderous sound returned by
the ripples little after the echo.