t the most
refractory iron or steel is melted to thin fluidity and so much excess
of heat imparted, that the mass will remain fluid, without further
heat, a considerable time. The temperature of the flame is not known,
though 4,000 or 5,000 deg. Fahr. has been suggested as an approximation.
This does not vitiate Prof. Langley's experiment, for he used it merely
as one of the most powerful artificial sources of light obtainable. His
method was to compare its light with that of the sun by an arrangement
that resembled a camera obscura, the light from the sun and the flame
being repeatedly superposed upon each other. The arrangement worked
admirably, and the observer was able to note the spots on the sun. He
found that the intensely hot flame was like a dark spot compared to the
sun's light and that the latter must be at least 2,168 times hotter
than the flame. This carries the result in favor of the largest
estimates. The flame of the convertor is not so hot as the melted
steel from which it comes, but it offers better opportunities for
observation. The steel itself as it was poured from the convertor was
found to be not more than one-sixty-fourth as hot as the sun.

DEAF MUTES IN POLAND.

Mr. George Darwin has brought forward statistics to prove that the
intermarriage of near relations does not have the unfavorable effect
upon offspring which is commonly supposed. But the director of the
Warsaw Institute for Deaf Mutes and the Blind combats this theory, and
says that the registers kept at that and similar institutions support
the popular opinion. The system of instruction at this asylum is very
perfect. Mimic language being almost totally prohibited, the pupils are
taught to understand the motion of the lips and to speak more or less
distinctly; and after a four years' residence in the Institute, they
generally attain in both a high degree of perfection. With great
judgment the managers have made the technical instruction at the school
of the best kind, so that the pupils readily find situations on
leaving, and indeed there are never enough to fill all the situations
offered. This appears to be the true method with students who would
otherwise find themselves at a disadvantage with more favored
competitors.

THE COMPASS PLANT.

The well-known dispute as to the "compass plant" has recently been
settled by Mr. Meehan in a manner which recalls the opinions of
judicial officers who deal with other than s