be made. The Doctor and his lady having
resumed their positions, we again observed,
upon the ground glass of the camera, the
artistic effect of the group in an inverted
miniature, coloured of course. This observation
was made with the head thrust under a
black velvet pall. Upon the ground glass we
saw drawn four squares, one within another,
and we remembered well what pictures we
had seen of trines and squares and houses of
the planets drawn by Albertus Magnus and
Agrippa. These were, however, squares, the
adept told us, corresponding respectively in
size to the plates, differing in price, on which
it is in the choice of the sitter to have a
likeness taken. A frame corresponding to
each size has the plate so fixed in it that,
when placed in the camera, it occupies
precisely the position of the square marked on
the glass. Our picture was to be of the third
size—the third square was to be the house
of Mars and Venus—and the object of the
operator was to arrange the sitters and the
camera in such a way as to procure a telling
group within the boundaries of that third
square upon the glass. This having been
done, and a fixed point supplied, on which the
eyes should feast, the velvet pall was thrown
over the back of the camera to exclude the
light, and a black stopper (the obturator) was
clapped over the glass in front, making
the chamber of the box quite dark. The
frame was then inserted in its place, the slide
removed, and the prepared silver reposing in
the darkness was laid open to receive the
meditated shock upon its sensibility. The sitters
were requested then to close their eyes for a
minute, that the eyelids might be rested,
then to look fixedly in the direction indicated
by a little picture pinned against a screen.
Then "Now, quite still; try to look pleasant
—a little pleasanter!" The cap was off, and
the two figures, fixed as statues, shone upon
the magic mirror in the camera, rigidly
pleasant. In half a minute,—counted accurately
by the operator—suddenly, the stopper
was again clapped over the glass in front;
the slide was let down over the tablet, upon
which light, having done its work, must
shine no more until the plate was light-proof.
Mars and Venus in conjunction having
entered the third house, we retired into the
necromancer's den to observe what would
follow.

The necromancer there addressed us in
manner following: "The chemical action of
light has decomposed the delicate compound
formed upon this tablet between the silver
and the chlorides of iodine and bromine.
The decomposition has been greatest, of
course, where the light has been most intense,
and its action has been manifested everywhere
by the piercing of the sensitive surface
with minute holes. Where the light has
been the strongest, the number of these
microscopic holes, contained upon a space
equal to the area of a pin's head, is greater
than in those parts on which the chemical
action of the light has not been so intense.
The portrait is thus minutely and delicately
dotted out, dots signifying light. That is the
sun picture which I now hold in my hand."
After this brief parliamentary address the
adept went on with his labour.

Still hiding his dark deeds from the face
of day he took the plate to a small bath of
quicksilver, from which a subtle vapour
slowly ascended, the quicksilver being placed
over the faint blue flame of a spirit-lamp.
Suspended over this bath it received upon its
polished surface the fine vapour; which,
penetrating into the minute holes formed by
light upon the plate, and there condensing
into microscopic drops, tinged out with its
own substance the surface on which light
had fallen—more abundant where its action
had been greatest, and less marked where
the decomposition had been less. When this
process was complete, the picture was
complete; all the lights being expressed and
graduated by a white metal, and the shadows
by the darker ground. There were the allied
images of gentleman and lady revealed
suddenly before us with a startling accuracy,
only unnaturally sensitive and altogether
wanting in stability of character.

Nothing remained then but to fix the
picture; to destroy the sensitiveness of the
surface. This was done by pouring over it
some dilute pyrogallic acid, and finally
submitting it to the action of a salt of gold;
of which a solution was washed over the plate,
and warmed upon it for one or two minutes.
The portrait was in this way perfectly spellbound.
It might be carried about loose in the
pocket and indiscriminately handled, without
suffering more hurt to its charms than can
be worked by those ugly disenchanters, grease
and dirt and scratches. For protection, however,
against these, and for the better setting
off of the picture, it will be delivered to its
owner as a well known imp was once sold, in
a bottle under glass; and as the Moors were
arch magicians, with traditions of Bagdad
about them, it will very fitly be enclosed in
a morocco case.

Truly, a fine picture it is. The lady's dress
suggests upon the plate as much delicate
workmanship as would have given labour for
a month to the most skilful of painters. The
lilies that we did not like upon the cape,
how exquisite they look here in the picture!
But as this group was destined to be coloured,
we were courteously invited to the colouring
room, a tiny closet in which two damsels
were busily at work, one upon a lady's dress,
the other upon the forehead of a gentleman,
putting in the yellow rather lavishly, but
with a good effect. "The faces," she informed
us, "must be coloured strongly, or they will
be put out by the bright blue sky." We
pointed to a small box labelled "Sky,"
remarking that the fair painters were magicians,
to carry the sky in a wafer-box. To which one