nd raise the mirror, M, by turning the button, B, and then
expose the plate. The sensitized plates are introduced into the apparatus
through the door, I, and are always brought automatically to the focus of
the objective through the pressure of the springs, R. The shutter of the
frame, B, opens through a hook, H, with in the pocket, N. After exposure,
each plate is lifted by means of the extractor, K, into the pocket,
whence it is taken by hand and introduced through a slit, S, behind the
springs, R, and the other plates that the frame contains. All these
operations are performed in the interior of the pocket, N, through the
impermeable, triple fabric of which no light can enter.

An automatic marker shows the number of plates exposed. When the
operations are finished, the objective is put back in the interior of the
camera, the doors, P and E, are closed, and the pocket is rolled up. The
apparatus is thus hermetically closed, and, containing all the
accessories, forms one of the most practical of systems for the itinerant
photographer.--_La Nature._

* * * * *

METEORITES.

In our SUPPLEMENT No. 529 we gave an abstract of Prof. Dewars recent
series of lectures on the above subject at the Royal Institution. We now
present an abstract of the last and concluding lecture.

THE DHURMSALA. METEORITE.

After the conclusion of his last lecture, Prof. Dewar distributed among
the younger listeners small pieces of a portion of the Dhurmsala
meteorite, which had been broken up for presentation to them by Mr. J.R.
Gregory, whose collection of rare minerals was recently to some extent
described in these pages. The lecturer stated that Sir F. Abel had given
him a large piece of a large meteorite, because he thought that the
speaker's piece ought to be bigger than theirs.

Professor Dewar also presented the listeners with a printed detailed
account of the fall of the Dhurmsala meteorite, including the report of
the occurrence sent to the Punjaub Government, and dated July 28, 1860.
The following are the main facts:

"On the afternoon of Saturday, the 14th of July, 1860, between the hours
of 2 and 2:30 P.M., the station of Dhurmsala was startled by a terrific
bursting noise, which was supposed at first to proceed from a succession
of loud blastings or from the explosion of a mine in the upper part of
the station; others, imagining it to be an earthquake or very large
landslip, rushed fr