The Sun.
London, England, 1839-01-26 00:00:00

PAIILEY'S TALES ABOUT MYTHOLOGY.

In One Volume, square 16m0., embellished with Seventy-seven
Cuts, price 4s. 6d. bound,
TALES ABOUT the MYTHOLOGY of
GREECE and ROME.

By PETER PARLEY,
Author of the Tales about Greece, Rome, &c.
London : Printed for Thomass Tegg, 73, Cheapside ; and may
be procured, by order, of all other Booksellers.

Just published, price Is.
A LETTER on the proposed PROTESTANT
LI.. MEMORIAL to CRANMER, RIDLEY and LATI-
MER, addressed to the Subscribers and promoters of that under-
taking.

By A. W. PUGIN.
London : Booker and Dolman, 61, New Bond-street.

CHEMICAL AND OPTICAL DIS-

COVERY.

( From the Constitutionnet )

. ,
At tie) last sitting of the Academy of Sciences, M. Arago
announced one of the most important discoveries in the fine
arts that have distinguished the present century, the author of
which has already acquired universal reputation by his miracu-
lous diorama—M. Daguerre. It is well known that certain
chemical substances, such as chlorate of silver, have the pro-
perty of changing their colour by the mere contact of light;
and it is by a combination of this nature that M. Daguerre
has succeeded in fixing upon paper prepared with it the rays
that are directed on the table of the camera obscure, and ren-
d-ring the optical tableau permanent. The exact representa-
tion of whatever objects this instrument is directed to is, as
everybody is aware, thrown down with vivid colours upon the
white prepared to receive them, and the rays of light that are
thus reflected have the power of acting in the way above al-
luded on chlorate of silver, or certain preparations of it. In
this manner an exact representation of light and shade of what-
ever object may be wished to be viewed is obtained with the
precise accuracy of nature herself, and it is stated to have all
the softness of a fine aquatint engraving. M. Daguerre had
mode this discovery some years ago, but ho had not then sue-
c,;eded in raakii4; the alteration of colour permanent on the
chemical substatiee. This main desideratum he has now ac-
comilished, and in this manner has been able, among other in-
tances, to make a permanent chemical representaticn of the
Louvre, taken from the Pont des Arts. M. Arago, in com-
menting upon this most extraordinary discovery, observed,
that a patent would be by no means able to preserve the rights
of the discoverer sufficiently to reward him for his efforts;
and he therefore urged the propriety of an application being
made to the legislature for a grant of public money as a recom-
pence. M. Biot, on the same occasion, compared M. Da-
guerre's discovery to the retina of the eye, the objects being
represented on one and the other surface with almost equal
accuracy.
What is the secret of the invention? What is the sub-
stance endowed with such astonishing sensibility to the rays of
light, that it not only penetrates itself with them, but pre-
serves their impression ; performs at once the function of the
eye and of the optic nerve—the material instrument of sensa-
tion, and the sensation itself? In good sooth we know nothing
about it. Figure to yourself, says a Parisian contemporary,
a mirror which, after having received your image, gives you
back your portreit, indelible as a picture, and a much more
exact resemblance. Such is the miracle invented by M. Da-
guerrc. His pictures do not reproduce colour, but only out-
line, the lights and shadows of the model. They are net
; aintint.,s, they are drawings: but drawings pushed to a degree
of verfection that art never can reach.
One has heard of writing by steam, but drawing by sunshine
(or moonshine) is a novelty for which the world is indebted to
M. Daguerre, of Paris, the diorama painter. M. Arago and
M. Biot, who have made reports to the Academy of Sciences
on the effects of M. Daguerre's discovery, have given up all
attempts to define its causes. The complaisance of the inven-
tor has permitted us to see these chef:v. d'ceuvre, where nature has
delineated herself. At every picture placed before our eyes we
were in admiration. What perfection of outline—what effects
of chiaro oseura—what delicacy —what finish l But how can we
be assured that this is not the work of a clever draughtsman?
As a sufficient answer, M. Daguerre puts a magnifying glass
in our hand. We then see the minutest folds of drapery,
the lines of a landscape, invisible to the naked eye. In
the mass of buildings accessories of all kinds, imperceptible
accidents, of which the view of Paris from the Pont des Arts
is composed, we distinguish the smallest details, we count the
stones of the pavement, We see the moisture produced by rain,
we read the sign of a shop. Every thread of the luminous
tissue has passed from the object to the surface retaining it.
The impression of the image takes place with greater or less
rapidity, according to the intensity of the light; it is produced
quicker at noon than in the morning or evening, in a summer
than in a winter. M. Daguerre has hitherto made his experi-
ments only in Paris; and in the most favourable circumstances
they have always been too slow to obtain complete results,
except on still or inanimate nature. Motion escapes him, or
leaves only vague and uncertain traces. It may be presumed
that the sun of Africa would give him instantaneous images of
natural objects in full life and action.