Star.
London, England, 1812-03-02 00:00:00

Rona INSTITUTION.

Mr. DAVY'S Birth Lecture was delivered on Satur-
day, the 29th of February. It related to radiant or
etherial substances, those forms of matter which are
known only in motion, and by their effects, and which
cannot be weighed or measured. The well known
agencies of radiant matter are of three kinds-Ist,
those agencies which produce vision-2d, those which
occasion heat—and 3d, those which occasion chemi-
cal changes. If a beam from the Sun, said he, be
passed through a prism, it is separated into rays,
which produce different colours, such as red, orange,
,yellow, green, blue, and violet; and into rays which
'produce heat, and rays which occasion particular
chemical effects ; the invisible rays which produce
heat, are more refrangible ; and those which occasion
chemical changes, /az refrangible than the coloured
rays. Rays that produce heat and light, and proba-
bly chemical effects, are disengaged in the combus-
tion of bodies; and rays that produce heat, seem to
be constantly emitted by bodies at the surface of the
earth, but in quantities smaller as their temperatures
are low. Mr. Davy exhibited an experiment in
which gunpowder was fired in the focus of a mirror
placed at ten or twelve feet from a small pan of char-
coal ;—and another experiment in which there was
an apparent radiation of cold from ice, but which he
exrlained by stating, that ice radiated less heat than
the air which it displaced. Metallic vessels,he said, as
Mr. Leslie had strewn, radiate less heat than porcelain,
or ',lass vessels, and heacc they are more fitted for
preserving liquids or meats hot ; pipes for heating
rooms, he said, should be polished where they arc in-
tended to retain heat, and covered with black pgint
or varnish where they are intended to give it off.—
He referred to the analogy between the powers of
radiant matter and electrified bodies, the most re-
frangible rays in the coloured spectrum, are analo-
gous in their powers to those of positive electricity,
theleast refrangible rays to theseof negative electricity.
*ll.. Davy seemed inclined to adopt, in preference to
all other views respecting radiant matter, those of
Newton. This great man supported them to be par-
ticles emitted from bodies having certain figures,
possessed of attractions and repulsions. But, said,
Mr. Davy, we are still in the infancy of this branch
of science, which promises in its extension to connect
together mechanical and chemical philosophy, and to
afford simple and sublime principles to this part of '
science: The agencies exerted by radiant matter,
said Mr. Davy, produce a number of important effects
in Nature, and by their relations to vision, give, as
it were, a language to the external world :-&•-without
this effect, said he, we should be limited to otsr own
globe t but by hi means we are incited to raise our
thoughts to the great scheme of the universe. to pass
from our transient and temporary existence, to laws,
which appear eternal in their operation—to recog-
nize one order in the immensity of space, and to in-
dulge hopes, that in the future progression of our be-
ing, we shall behold fully that magnificent system,
which we now see darkly and at a distance.

The new Comet passed Aldebaran in Tooth about
the 15th of January, and, was then advancing north-
ward, nearly at the rate of a degree per day. It was
very faint, and is supposed to have passed its perihe-
lion. The great Comet of 1811 is now completely '
'out of sight.
While Messrs. Bett and LANCASTER are fsriottsiy
contending for the honour of an ancient invention of
the Hindoos, the genuine British, and truly national,
ISystem of Teaching by interrogatories, is modestly
making its way iuto all our independent seminaries,
in the. Universal Preceptor of Blair, the British Geo.
Igraphy of Goldsmith, the Historical Questions of
Adak, gip &Aiwa gi Darrow.