170 M iscellanies. 
years, and having at length attained his object has declared his discove- _ 
ries and claimed the invention as his own. Full and satisfactory deserip- 
tions are promised by M. Arago and two other scientific engineers ap- 
pointed to report on the subject, and in the interval a slight outline has 
been given in the French papers, fiom which the following account is 
tak ; 
en. 
A polished metallic plate is the substance made use of, and being pla 
ced within the apparatus is in a few minutes removed and finished by a 
slight mechanical operation. The sketch thus produced is in appearance 
something similar to aquatint, but greatly superior in delicacy ; and such 
is the extraordinary precision of the detail that the most powerful micros- 
cope serves but to display the perfection of the copy. The first efforts of 
the inventor were directed towards architectural subjects, and a view of 
the Louvre and Notre Dame are among the most admired of these engra- 
vings. In foliage he is less successful ; the constant motion in the leaves 
rendering his landscape confused and unmeaning ; and the same objection 
necessarily applies to all moving objects, which can never be properly de- 
lineated without the aid of memory. But in the execution of any station 
ary subject, buildings, statues, flowers, the leaves of plants, or the bodies 
of animals, the fac-simile is perfect; and the value of the invention may 
therefore be easily conceived. 
Several eminent artists have examined the designs, and were equally 
delighted with the precision and delicacy of the representation. Am 
the sketches exhibited by the projector was a marble bas-relief and plas 
ter imitation; the first glance was sufficient to detect the difference be- 
these two; and in three views of a monument taken in the morlr 
ing, noon, and evening, the spectators easily distinguished the hours at 
which they were executed, by the difference of the light, though in the 
first and last instances, the sun was at an equal altitude. 
But perhaps the anatomist or zoologist will derive the greatest advan- 
tages from the discovery, the form of the animal being as easily studied 
from the drawing as from the original, and the most powerful microscopes 
not having hitherto detected the smallest deficiency in the details. Not 
is the invention devoid of interest to the astronomer, for the light of the 
moon is sufficient to produce the usual results, requiring only additional 
time for its operations. The following extract from “ Le Commerce” 18 
sufficient to substantiate its value in this respect :—‘ The experiments on 
the light of Sirius have confirmed the testimony of natural philosophy, and 
abundantly proved that the stars are bodies of the same nature as the sun ; 
at the request of M. Biot, M. Daguerre has submitted his apparatus t0 the 
influence of the light of the moon, and has succeeded in fixing the image 
of that luminary. We observed that the image had a trail of light some 
thing like the tail of a comet, and we ascribe it to the movement of the 
body during the operation, which is of much longer duration than that + 
the light of the sun.” 
