ulated for the effect to be produced.
Opposite the vacant space left by the two cores, there is a small
piece, t, of rectangular form, and also of soft iron, fixed to a
vibrating strip of firwood, L, of about 4 inches section. The
periodical breaking of the circuit produced by the transmitter causes
a variation in the magnetization of the iron cores of the five
receivers and makes the firwood strips vibrate energetically. These
vibrations are received and poured forth as it were in front of the
telephone pavilion, by large brass trumpets arranged in front of each
receiver, as shown in Fig. 3.

[Illustration: FIG. 3.--THE ADER FLOURISH OF TRUMPETS]

It would be difficult for us to pass any judgment whatever upon the
musical and artistic value of these transmissions of trumpet music to
a distance; we prefer to confess our incompetency in the matter. But
it is none the less certain that these experiments are having the same
success that they had at their inception in 1881 at the Universal
Exposition of Electricity, and they allow us to foresee that there is
a time coming in which it will be possible to transmit speech to a
distance with the same intensity that the present trumpet flourishes
have. Although all the tentatives hitherto made in this direction have
not given very brilliant results, we must not despair of attaining the
end some day or other. Less than fifteen years ago the telephone did
not exist; now it covers the world with its lines.--_La Nature._

[Illustration: Fig. 4.--DETAILS OF THE RECEIVER.]

* * * * *

NOTES ON DYEWOOD EXTRACTS AND SIMILAR PREPARATIONS.

By LOUIS SIEBOLD, F.I.C., F.C.S.

During the last ten years there has been an enormous increase in the
production of these preparations, and the time will come when their
application in dyeing and calico printing will become so general as to
completely supersede the employment of the raw materials. The
manufacture of these extracts, to be thoroughly successful, requires
to be so conducted as to secure the perfect exhaustion of the dyewoods
without the slightest destruction or deterioration of the coloring
matters contained in them; and though nothing like perfection has been
reached in the attainment of these objects, it is certain that the
processes of extraction and evaporation now employed by the best
makers are a very great improvement on the older methods. Indeed,
there is no difficulty nowadays in pr