A NEW OR IMPROVED METHOD OF OBTAINING THE SPONTANEOUS REPRODUCTION OF ALL THE IMAGES RECEIVED IN THE FOCUS OF THE CAMERA OBSCURA
Year: 1839

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, MILES BERRY,
of the Office for Patents, 66, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent, under the Great Seal of Great Britain, bearing date at
Westminster, the Fourteenth day of August, in the third year of Her
reign, and in the year of our Lord One thousand eight hundred and thirty-
nine, did, for Herself, Her heirs and successors, give and grant unto me,
the Miles Berry, Her especial license, full power, sole privilege and autho-
rity, that I, the said Miles Berry, my executors, administrators, and assigns,
and such others as I, the said Miles Berry, my executors, administrators, or
assigns, should at any time agree with, and no others, from time to time and at
all times during the term of years therein mentioned, should and lawfully
might make, use, exercise, and vend, within England, Wales, and the Town
of Berwick-upon-Tweed, and in all Her Majesty's Colonies and Plantations
abroad, an Invention of "A NEW OR IMPROVED METHOD OF OBTAINING THE
SPONTANEOUS REPRODUCTION OF ALL THE IMAGES RECEIVED IN THE FOCUS OF THE
CAMERA OBSCURA," being a communication from a foreigner residing abroad;
in which said Letters Patent is contained a proviso, obliging me, the said
Miles Berry, by an instrument in writing under my hand and seal, particularly
to describe and ascertain the nature of the said Invention, and in what manner
the same is to be performed, and to cause the same to be inrolled in Her

page_text: Majesty's High Court of Chancery within six calendar months next and
immediately after the date of the said in part recited Letters Patent, as in
and by the same, reference being thereunto had, will more fully and at large
appear.
NOW KNOW YE, that in compliance with the said proviso, contained in
the above in part recited Letters Patent, I, the said Miles Berry, do hereby
declare that the nature of the said Invention, and the manner in which the
same is to be performed, are particularly described and ascertained in and by
the following description thereof, reference being had to the Plates of Draw-
ings hereunto annexed, and to the letters and figures marked thereon (that is
to say):-
Before proceeding to the description of this Invention, I think it proper to
make the following remarks.-This Invention or discovery relates to photo-
genic drawing, or the spontaneous reproduction of images, pictures, or repre-
sentations of nature by the action of light, that is, by the process or method
now well known under the name of "daguerreotype." I believe it to be the
Invention or discovery of Messrs. Louis Jacques Maude Daguerre and Joseph
Isidore Niepce, junior, both of the kingdom of France, from whom the French
government have purchased the Invention, for the benefit of that country.
This Invention or discovery was fully communicated to me by a certain
foreigner residing in France, on or about the fifteenth day of July, in the year
One thousand eight hundred and thirty-nine, with instructions immediately to
petition Her Majesty to grant Her Royal Letters Patent for the exclusive use
of the same within these kingdoms, and in consequence thereof I did apply
for such Letters Patent, and Her Majesty's Solicitor-general, after hearing all
parties who opposed the same, was pleased on or about the Second day of
August, now last past, to issue his report to the Crown in favor of the Patent
being granted, and it consequently passed the Great Seal in the usual course,.
being sealed on the day above named, which is some days prior to the date of
the exposition of the said Invention or discovery to the French government
at Paris by Messrs. Daguerre and Niepce, according to the terms of their
agreement.
And I will now proceed to describe this Invention or discovery, as com-
municated to me.
DESCRIPTION OF THE PROCESS.
The reproduction o
magos received at
TOM BU LANG TULUS of the camera unsure
CHIC IUCUS DI
is effected on plates or surfaces of silver, which may be plated on copper,
the copper serving to support the surface or sheet of silver, the combination:

page_text: The
of these two metals contributing towards the..perfection of the effect.
silver employed should be without allow, or as pure as possible. The sheet of
copper should be sufficiently thick to preserve the perfect smoothness and
flatness of the plate, so that the images may not be distorted by the warping
thereof, but the copper should not be thicker than what would be required to
attain that end, on account of the weight of the metal. The thickness of the
two metals united need not to exceed that of a stout card.
The process is divided into five, operations. The first consists in polishing
and cleaning the silver surface of the plate in order to properly prepare or
qualify it for receiving the sensitive layer or coating, upon which the action of
the light traces the design. The second operation is the applying that sensitive
layer or coating to the silver surface. The third, in submitting in the camera
obscura the prepared surface or plate to the action of the light, so that it may
receive the images. The fourth, in bringing out or making appear the image,
picture, or representation, which is not visible when the plate is first taken out
of the camera obscura. The fifth and last operation is that of removing the
sensitive layer or coating, which would continue to be affected and undergo
different changes from the action of light; this would necessarily tend to
destroy the design or tracing so obtained in the camera obscura.
DESCRIPTION OF THE FIRST OPERATION.-PREPARING THE SILVER
SURFACE OF THE PLATE.
For this operation are required a small phial of olive oil, some cotton very
finely carded, a small quantity of pounce or pumice powder, ground. extremely.
fine, and tied up in a small bag of muslin, sufficiently thin in texture to allow
the powder to pass easily through when the bag is shaken, a phial of nitric
acid, diluted with pure water, in about the proportion of one part of acid to
sixteen parts of distilled water, a wire frame or stand, on which the plates can
be placed so as to be heated by means of a lamp; lastly, a spirit or other lamp
to heat the plates. The size of the plates or surfaces are limited by the
dimensions of the apparatus. The plates must first be well cleaned and
polished. To effect this, begin by sprinkling. the silver surface with pounce,
by shaking the bag without touching the plate, and then with cotton impreg-
nated with a little olive oil rub it gently on, lightly moving the hand. round
in circles from the centre c (see Fig. 2, Plate 1.) The plates during this
operation should be placed flat on sheets of paper, which must be changed
when necessary. The pounce must be sprinkled several times, and the cotton
changed several times during the operation of rubbing. The pestle and mortar
used for pulverizing the pounce or pumice powder should not be formed either

page_text: of cast iron or copper, but made of porphyry. The pounce should be ground
afterwards on a glass plate, with a glass muller, pure water being used in the
operation. The pounce should be used only when perfectly dry. It will be
readily conceived how important it is that the pounce or pumice powder should
be sufficiently finely pulverized so as not to cause streaks or scratches on the
silver surface, for it is in a great measure upon the fine polish of the surface
of the plate that depends the beauty of the image, picture, or tracing pro-
duced thereon. When the plate is perfectly polished it must then be cleaned.
This is effected by dusting or sprinkling the powder over the surface, and
rubbing it with dry cotton, the movements of the hand being made in circles
and backwards and forward, and up and down, crossing each movement in
order to operate fully on all parts of the surface. This is the best mode of
rubbing to gain the desired result. Next a small knot or tuft is made with
carded cotton, which is to be moistened with a little acid diluted in water, as
above stated. To do this the knot of cotton may be placed on the mouth of
the bottle containing the diluted acid, and pressed thereon, the phial being then
inverted and then placed again upright, so that the centre of the tuft of
cotton may be moistened with acid without deeply impregnating it. Very
little acid is required, and care must be taken not to wet the fingers with
it. With this tuft so charged with acid the surface must be rubbed, care
being taken to carry the acid uniformly over all parts of the surface of the
plate. The cotton should be changed several times, and the rubbing of the
surface be made by moving the hand round and round, and crossing as before,
so as to extend equally the acid, which, nevertheless, ought to do no more
than cover slightly the surface of the plate. It will sometimes happen that
the acid applied on the surface of the plate will be found to accumulate into
small globules; these must be destroyed by changing the cotton, and by
rubbing the plate gently, so as to spread evenly the acid, for on any place
where the acid has been allowed to rest a time, or has not been laid evenly, it
would form spots or stains. It will be seen that the acid is evenly spread upon
the surface of the plate by its appearing covered with a uniform tint, or what
may be termed a thin veil or change of surface. The plate is finally to be
sprinkled with pounce or pumice powder, and cleaned by slightly rubbing it
with a piece of carded cotton. Instead of ordinary pounce, calcined Venetian
tripoli may be used. The plate thus prepared is then to be submitted to a con-
siderable degree of heat. To do this it is placed on a wire frame such as shewn
at Fig. 1 and 1 bis (Plate 1), the silver surface being uppermost; under the plate
is to be placed a lighted lamp, which is to be moved about so that the flame
shall act equally upon all parts; when the plate has been submitted for about

page_text: five minutes to this operation (or until the heat has acted equally upon all
parts of the plate), it will be perceived that the surface of the silver has
obtained a whitish tint or coating, and then the action of the heat must cease.
This effect may be obtained by other means, for instance, the heat of lighted
5 charcoal may be used, which may be preferable, as the operation will be
sooner finished. In this case the wire frame is unnecessary, for the plate may
be laid on the stove, or held with tongs, the silver surface always being
upwards, and it may be moved backwards and forwards on the furnace so as
to heat it equally throughout, until the silver surface becomes covered with a
whitish tint as above stated; the plate is next to be cooled rapidly by placing
it on a cold body or substance, such as a marble slab or stone, or metal
surface; when cooled it must be polished again. This may be quickly done
since it is only necessary to remove the white tint which has been formed on
the silver surface. To effect this, the plate is to be sprinkled with pumice
powder and rubbed in a dry state with a portion of cotton; this should be
done on the surface of the plate several times, taking care to change the
cotton often; when the silver is well polished, it is to be rubbed as above
stated, with acid dissolved in water and sprinkled with a little dry pounce
powder, and rubbed slightly with a knot of cotton. The acid is then to be
laid upon the plate, say three different times, care being taken to sprinkle each
time the plate with powder, and to rub it dry and very lightly with clean cot-
ton; care should be taken not to breathe upon the plate or touch it with the
parts of the cotton touched by the fingers, as the perspiration would produce spots
or stains, and dampness of the breath or of the saliva would produce the same
defects in the drawings. When the plate is not intended for immediate use
or operation, the acid may be used only twice upon its surface after being ex-
posed to the heat. The first part of the operation may be done at any time.
This will allow of a number of plates being kept prepared up to the last
slight operation. It is, however, considered indispensable that just before the
moment of using the plates in the camera, or the reproducing the design, to
put at least once more some acid on the plate, and to rub it lightly with
pounce as before stated; finally the plate must be cleaned with cotton from
all pounce dust which may be on the surface or its edges.
SECOND OPERATION.-COATING THE SURFACE..
For this operation are required the following implements:-The box repre
sented in Plate 2, Figures 1 and 2; the thin board or frame shewn in Plate 1,
Figs. 3; four small metallic bands, of the same metal as the plates (seen also
in Figs. 3); a small handle as at Fig. 5, Plate 1; and a box of small nails or

page_text: tacks; a phial of iodine. After having fixed the plate upon the thin board or
frame (the silver surface uppermost), by means of the metallic bands and the
small nails which are forced into the board by the handle, some iodine is then
to be put into the cup or dish D, placed in the bottom of the box, Plate 2,
Fig. 1. It is necessary to divide the iodine into pieces, in order to render the
exhalation more extensively and equally diffused, otherwise on the middle of
the plate will be formed circles, or a kind of iris, or appearance of a rainbow,
in prismatic colours, which would prevent the plate froin receiving a uniform
impression. The thin board with the plate is then placed with the silver
surface undermost, upon small brackets or supports at the four angles of the
box; its cover G is then closed. In this position the plate must be left until
the surface of the silver be covered with a fine golden tinge, which is caused
by the evaporation of the iodine condensing upon the surface of the silver. If
the plate were allowed to remain too long, this golden yellow colour would
turn purple or violet colour, which must be avoided, because in this state the
coating is not so sensitive to the effect of light; on the contrary, if this coating
is too pale or not sufficiently yellow, the image taken from nature would be
very deficiently or faintly reproduced, therefore a coating of a golden yellow is
particularly desired, because it is the most favorable to the production of the
effect. The time necessary for this operation cannot be stated, because it de-
pends on several circumstances; one is the temperature of the room wherein
the operation is conducted; another the state of the apparatus, for this process
should be left to itself, and not be affected by the addition of any other heat
than that of the room. It is very important in this operation that the
temperature inside the box be equal to that outside; if such were not the case
on the plate being passed from a cold to a warm atmosphere, it would become
covered with condensed moisture from the atmosphere, which would do
great injury to the effect. This operation should be left entirely to the
spontaneous evaporation of the iodine; also the more this box or appara-
tus is used the less time is required to effect the object, because the
interior sides of the box become penetrated with vapour of iodine, and as
it is the nature of this vapour always to evaporate, it will arise from all
the internal parts of the box, and therefore will spread more evenly and
more quickly on the surface of the plate, which is very important; therefore
it is proper to leave a little iodine in the cup on the bottom of the box, and
also to keep the box free from damp. It is therefore evident that the appa-
ratus will operate better after being used several times. From the causes
above stated it is not possible to fix precisely the time necessary for obtaining
the coating of golden yellow tint, as the same may vary from five to thirty

page_text: minutes, but rarely longer, unless the weather be very cold. It is necessary
to look at and examine the state of the plate from time to time, to ascertain
whether it has attained the golden yellow tint required; but it is important that
the light should not be allowed to fall or strike directly upon its silver surface.
It may happen that the plate be more colored or tinted at one end than at
the other; in that case, in order to equalize the tint, care must be taken in re-
placing the plate to turn it endways or side for side. In order to accomplish
these repeated examinations without injuring the sensitive ground or coating,
this process should be conducted in a darkened room, into which light is ad-
mitted sideways, not from the roof. The box should be placed in a dark room
where the light enters but feebly, as through a door left ajar. When the
plate is to be inspected, the operator raises the lid of the box, when the board
may be taken by its edges with the two hands and turned up rapidly, very
little light being required to shew the true colour of the coating, and if the plate
has not obtained the golden yellow tinge, it must be immediately replaced in the
box and there kept until it attains the proper gold colour; if on the contrary
the colour is deeper, then the coating will not be of any use and the plate is to
be repolished and cleaned, the first operations being recommenced from written
description. This operation may seem difficult and tedious, but with a little
practice, an intelligent operator would be enabled to judge accurately of the time
required to obtain the desired golden yellow tint, and also to inspect rapidly
the plate, so as not to give the light sufficient time for acting upon the coating;
when the surface of the plate has attained the proper colour, the board with
the plate must be introduced into the frame represented at Figs. 1, 2, 3, 4,
Plate 3, which frame is adapted to the camera obscura. In this transference
care must be taken to prevent the light striking on the surface of the plate, and
for this purpose the camera obscura may be lighted with a wax taper, the light
of which has much less effect upon the coated surface; even this light ought
not to be allowed to strike too long on the plate, as it will cause marks or
traces on the same if allowed to continue a long time. After this second opera-
tion is completed, the plate is to be passed to the third operation, or that of
the camera obscura; whenever it is possible the one operation should imme-
diately follow or succeed the other. The longest interval between the two
should not exceed an hour; beyond this time the action of the iodine and
silver surface will lose their requisite photogenic properties. But previous
to passing to the third operation I would add the following remarks or
observations.

page_text: only open on one of its sides. The board saturated with iodine may be made
to serve to coat several plates during a whole day, or even several days,
without the necessity of replacing it in the iodine or saturated box.
I will now proceed to describe the next operation.
THIRD OPERATION.
THE CAMERA OBSCURA.
As before stated, the operation should proceed as quickly as possible from
the second to the third operation, as this time the combination between the
iodine and the silver has no longer the same property. The apparatus
necessary for this operation is the camera obscura (see Plate 4, Figures 1
and 2) adapted and fitted to receive the prepared plates and their boards.
This third operation is that in which by means of light acting through the lens
of the camera obscura, nature reflects or impresses (to use figurative language)
an image of herself, of all objects enlightened by the sun on the surface of
photographic or prepared plates. The objects (of which the image is to be
retained upon the surface of the plate) should be as much as possible lighted
by the sun, because then the operation is more expeditious. It is easy to
conceive that this operation being produced only by the agency or effect of
light, that the action is the more rapid according as the objects are more
brilliantly lighted up or illuminated, or in their nature are more intensely white
or present bright lines or surfaces. After having placed the camera obscura
opposite to or in front of the objects of which it is desired to fix or retain the
image, or obtain a representation, it is essential first to properly adjust the
focus of the camera obscura so that the objects be represented perfectly clear
and distinct; this is easily done by moving forward or backward the frame of a
plate of ground glass in the camera, which glass receives the images of the
objects from the lens. When this frame is brought to the proper position,
this moveable part of the camera obscura is fixed by means of screws applied
for that purpose; the ground glass is then removed from the instrument, care
being taken not to move the camera obscura, and in the place of the ground
glass is substituted the apparatus carrying the prepared metallic plate or
surface (see Figures 1, 2, 4, and 5, Plate 3), which apparatus exactly fits the
place of the ground glass plate on its frame; during the time the apparatus
with the prepared surface is being fastened in to the instrument by small brass
buttons or other fastenings, the camera obscura is closed. The obscuring
shutters or doors B, B, of the apparatus are then opened by means of the two
semicircles A, A; the plate is then in a proper position to receive and retain
the impression of the image of the objects chosen. Nothing more need be done

page_text: but to open the aperture of the camera obscura, and to consult a watch to
reckon the minutes the prepared surface shall be under the action of the light.
This operation is of a very delicate nature and should be carefully attended to,
because nothing is visible, and it is quite impossible to state the time necessary
for the reproduction of the image, as it depends entirely on the intensity of light
received by or from the objects, the image of which is intended to be repro-
duced, the time may vary from three to thirty minutes. It must likewise be
remarked that the seasons as well as the hours of the day have great influence
on the rapidity of the operation. The most favorable hours are from seven
in the morning till three in the afternoon. The process of reproduction, which
may require from three to four minutes in the months of June and July, will
require from five to six in the months of May and August, from seven to eight
in April and September, and so on in proportion as the seasons advance. This
is only a general and approximate statement for objects strongly lighted, as it
often happens that twenty minutes are necessary for the operation in the most
favorable months, that is, when the objects are partially in shadow or dark-
ness. It will be seen from what has been stated that it is impossible to name
exactly the time necessary for obtaining images or tracings from nature (or
photographic designs), but by a little practice it may be easily ascertained;
practise is the only sure guide, and with this advantage an operator will
readily assertain the required time correctly. Latitude of the situation is, of
course, to be considered; for example, it is conceived that in the south of
'France, and generally in all the countries where the light is very intense, as in
Spain or Italy, the plates will receive the impression much more rapidly; it is,
however, very important not to allow more time to pass than what is necessery
for the reproduction, because the clear parts would no longer be or remain
white or clear, they would be darkened by the prolonged action of the light
allowed to strike upon the iodine on the surface. If, on the contrary, the time
allowed is not sufficient, then the proof or image would be vague, and without
'proper details. Supposing the operator has failed in one proof, it being
imperfect on account of its having been withdrawn too soon or left to remain
too long, another may be begun immediately, a plate having been previously
prepared, the operator is then more certain of obtaining the proper effect, the
second operation being corrected by the first. It is desirable and useful, in
order to acquire a proper practice, to make some experiments of this kind,
the plate or surface having been submitted to the action of the light the
'required time.
Tosed to dozasike the fourth operation

page_text: The operator must hasten to submit the surface of the plate to the fourth
operation, as soon as it is withdrawn from the camera obscura; not more than
one hour ought to be allowed to expire between the third and fourth operations,
and it is much more certain to obtain good proofs or tracings of nature when
the fourth operation takes place immediately after the third; for this
fourth operation are required the following implements, first, a pliial containing
a quantity of mercury or quicksilver; second, a spirit or other lamp; third,
the apparatus represented in Plate 5, Figures 1, 2, 3; fourth, a glass funnel
with a long neck. By means of the funnel the mercury is poured into the
cup C, situated in the bottom of the apparatus (shewn in the Figures), and in
a sufficient quantity to cover the ball or globe of the thermometer F; from
this time no daylight must be admitted, and the room must be darkened, and
the light of a candle or taper only be used to enable the operator to inspect
the progress of the operation. The board on which is fixed the plate must be
withdrawn from the apparatus already mentioned as adapted in the camera,
(see plate 3, Fig. 4), which apparatus preserves it from the contact of light:
The thin board with the plate is then introduced in the grooves or ledges of
the blackened board B, plate 5,' Fig. 1; this black board is then replaced in
the box or apparatus, which maintains it at an inclination of 45 degrees, the
prepared metal surface being placed undermost, so that it may be seen through
the side glass G; the cover A of the box must be put down gently to prevent
any particles of mercury flying about in consequence of the compression of the
air; when the whole is thus prepared, the spirit lamp is lighted and placed
under the cup containing the mercury, and allowed to remain until the
thermometer (the ball of which is immersed in the quicksilver bath, the tube
extending outside the box) indicates a temperature of sixty degrees centi-
grade, the lamp then must be renioved. If the thermometer has rapidly risen
it continues to rise even when the lamp is removed, but it should not be
allowed to rise above seventy-five degrees contigrade. The impression of the
image of nature now actually exists on the plate, but it is not visible; it is only
after several minutes of time has elapsed that faint tracings of the objects begin
to appear, as may be readily ascertained by inspecting the operation or looking
through the glass, assisted by the light of a candle or taper, which must not be
allowed to strike too long on the plate, because it would leave marks on the
same. The plate should be left in the box until the thermometer has fallen forty-
five degrees, then the plate is to be taken out, and this operation is finished when
the objects or articles (the reproduction of the images of which it is intended

page_text: to be produced) have been highly illuminated, and the light has acted a little
too long in the camera obscura; this fourth operation will be finished
even before the thermometer has gone down to fifty-five degrees; this effect
may be perceived by looking through the glass G. It is necessary after each
operation to wipe or clean well the interior of the apparatus, in order to
remove the slight coating or layer of mercury which generally covers or adheres
to it. The black board or frame B must likewise be carefully wiped, that it
may not retain any particles of quicksilver. When the apparatus is to be
packed up for carrying it from place to place, the mercury which is in the cup
must be poured into the phial, this is done by inclining the box so as to let
the mercury escape through the small cock E at the side of the apparatus.
The picture or plate may now be inspected by means of a weak light, in order to
ascertain whether the operation has succeeded or not. It may be taken off
from the thin board by removing the metallic bands or straps, which bands
should be cleaned carefully from any iodine or mercury they may have received
by means of pounce and a little water; this should be done after each tracing
is taken, or plate operated upon. It will be readily conceived that this
cleaning is necessary, since not only these small bands are covered with a
coating of iodine, but they have also received a portion of the tracing from
nature. The plate is then to be placed in a box provided with a cover and
grooves, as represented in Plate 2, Fig. 3, until it can undergo the fifth and
Jast operation. This operation need not be effected immediately, for the plate
or sketch may be kept in this state for several months without undergoing any
alteration, provided, however, it be not frequently inspected or exposed in the
open daylight. I will now proceed to the last operation, viz., the-
FIFTH OPERATION.-FIXING THE TRACING, DELINEATION, OR PICTURE.
The object of the fifth operation is to remove from the surface or plate the
coating of iodine, which otherwise, on its being exposed too long to the action
of light, would continue to be decomposed, and would thereby destroy the
picture or tracing. For this operation are required the following articles :-
First, water saturated with sea salt or a weak solution of byposulphite of pure
soda; secondly, the apparatus represented in (Plate 6, Figs. 4 and 4 bis);
thirdly, two troughs of metal, as shewn in (Plate 6, Figs. 2 and 2 bis);
fourthly, a vessel or jug full of distilled water, as (Plate 6, Fig. 4). In order
to remove the coating of iodine, the operator must take the common salt, and
put it into a bottle with a large mouth, the bottle being filled with pure water.
To accelerate the dissolving of the salt, the bottle may be shaken from time to
time when the water is completely saturated (that is, when it will dissolve no

page_text: more salt), it is to be filtered through blotting-paper that no extraneous
matters may remain in it, and that it may be perfectly clear; water saturated
with salt may be prepared in sufficient quantity beforehand, and kept in
corked bottles; by this means the necessity and inconvenience of preparing it
every time is avoided. Into one of the troughs the salt water is to be poured
until it is about an inch in depth, the other trough is to be filled with pure
water. These two liquids are warmed or heated in temperature, though not
to the boiling point. In place of the solution of salt may be substituted a
solution of byposulphite of pure soda; this latter is even preferrable, because
it completely removes the iodine, which is not always the case when sea salt
is used, especially if the designs or tracings have been obtained some time, and
laid aside between the fourth and fifth operations. The mode of operation,
however, is the same for the two solutions, although the solution of hyposul-
phite does not require to be warmed, and a less quantity of it is required than
of the salt and water, since it is sufficient that the plate should be covered
with the same when laid on the bottom of the trough. The plate is first to
be immersed in the pure water contained in one of the troughs; it must only.
be dipped in and drawn out immediately; it is sufficient that the surface of
the plate be covered with water, and then without allowing it to dry it is to be
plunged immediately in the salt water. If the plate is not dipt in pure water,
before immersing it in salt water or in the solution of hyposulphite, these solu
tions would make marks or spots on the surface of the plate. To facilitate the
action of the salt water, or of the hyposulphite, which absorbs the iodine, the
plate should be moved about in the liquid by means of the small hooked
instrument, as shewn at (Fig. 3, Plate 6), the end of it being placed under
the plate, so as to raise it and let it drop several times, thus producing a gentle.
washing of the surface. When the yellow colour or tint of the iodine is entirely
removed from the surface of the plate, it is to be removed and carefully taken
by the edges, so as not to touch or injure the drawing, and then dipt imme-
diately in the first trough of pure water. The apparatus shewn in Plate 6,
Fig. 4 and 4 bis, and the vessel, Fig. 5, are then brought into use; these
must all be perfectly clean, and the vessel, Fig. 5, filled with distilled water,
which should be hot, but not boiling; the plate on being withdrawn from the
trough of water is to be placed immediately on the inclined plane, E, Fig. 4,
Plate 6, and without allowing it time there to dry. The operator is then to
pour upon the surface bearing the drawing the hot distilled water, beginning
at the top of the plate, and pouring the water over it in such manner that it
shall flow over the surface, and carry away with it all the solution of sea salt
or of hyposulphite, which has been already considerably weakened by the immer-

page_text: sion of the plate in the first trough. If the hyposulphite solution has been used;
the distilled water to be poured over the surface need not be so hot as for the
common salt solution. Not less than a quart of hot distilled water is required
for thus washing the surface of a plate measuring eight or nine inches long by
six or seven inches wide. It sometimes will occur, that after having poured
warp water on the surface, some drops or globules of water will remain on the
plate. In this case they must be removed before they have time to dry, as they
might contain some particles of sea salt or iodine, and injure the drawing; they
are readily removed by strongly blowing on the plate. It will be understood how
important it is that the water used for this washing should be perfectly pure,
for part of it will dry on the surface of the plate, notwithstanding the rapidity
with which it may have passed over it; and if it contains extraneous matter,
then numerous and indelible spots would be formed on the drawing or tracing.
In order to ascertain that the water is suited for this washing, a drop may be
heat, it leaves no
let fall on a burnished plate, and if, when evaporated
stain or mark behind, it may be employed without fear; distilled water is
When this
always sufficiently pure for this operation without testing it.
washing is completed, the picture, drawing, or tracing is finished; the only
thing now to be done is to preserve the surface from being touched, also from
dust and from vapours which tarnish silver. The mercury which traces the
images, or in other words by the action of which the images are rendered
visible, is partly decomposed, it adheres to the silver; it resists the washing by
the water poured upon it by its adhesion, but it will not bear any rubbing or
touching. To preserve these drawings they must be covered with glass, securely
placed a little above the surface, both the edges of the glass and plate
secured by pasted paper or other means, and they are then unalterable, even
by the light of the sun. It may happen that in travelling the operator may
not be able conveniently to thus secure the plates; they may be preserved by
enclosing them in a box, similar to the one represented, Plate 2, Fig. 3; for
greater safety, small bands of paper may be pasted over the junction of the
box and its cover. It may be necessary to state that the silver surfaces may
be used several times in succession, provided the silver be not polished or
ground through to the copper. And it is very important to remove after each
time of using the mercury traced on or adhering to the surface, which is to be
done, as before described, by means of pounce or pumice powder and oil, and
by changing the cotton often, otherwise the mercury would finally adhere to
the silver, and the proofs obtained on that combination would always be
imperfect, because they would be deficient both in vigour and clearness..

page_text: EXPLANATION OF THE DRAWINGS HEREUNTO ANNEXED OF THE APPARATUS USED
IN THESE PROCESSES OR OPERATIONS OF THE DAGUERREOTYPE.
Plate 1, Fig. 1, represents a plan view of a wire frame; Fig. 1 bis is a
side view of the same; this frame serves to receive the plates when they are
to be heated by the spirit lamp, as shewn at B, Fig. 6; A, being its cover or
stopper to prevent the spirit evaporating when the lamp is not in use; Fig. 2
represents a plate with a silver surface, upon which the tracing is to be taken.
Its size may be varied at pleasure. To make tracings of large dimensions the
focus of the object glass must be increased, as also all the other parts of the
apparatus; Fig. 2 bis shews the edge or thickness of the plate; it may be very
thin, but it is essential it should have a very flat surface; Fig. 3 is a plan view
of the thin board or tablet on which is fixed the plate for the subsequent
operations. The plate is secured on it by means of four thin metal bands B
(one of them being shewn detached above, Fig. 3 bis), plated with silver'; they
should be of the same thickness as the plate; these bands are fixed on the
board by small nails, forced or driven into the board through holes D, by
pressing the handle, shewn at Fig. 5, upon them; the surface of these bands
being nearly level with that of the plate, retain it by small projections or pièces
soldered on them, as seen in the Drawings. These metallic bands have two
offices to perform, one to secure the plate, and the other to facilitate the
equalization of the coat of iodine, which might otherwise be more intense on
the edges or borders of the plate than on its centre; Fig. 3 bis shews the board
and plate, as seen edgeways; Fig. 4 represents the muslin bag containing the
pounce or pumice powder.
Plate 2, Fig. 1, is a vertical section of the iodine box or apparatus taken
in, the line A, B, Fig. 2, wherein the coating of iodine is obtained upon the
silver surface; Fig. 2 is a plan view of the same; C is an interior cover closing
the lower part of the box; it serves when the apparatus is not. in opération
to concentrate the evaporation of the iodine, which condenses on the wooden
surface of this part of the box; D is the cup or dish for containing the iodine;
E is the thin board to which is fixed the plate (as represented in Plate 1, Fig. 3.),
the silver surface. being downwards, it is thus placed in order to obtain the
coating of iodine as the vapour thereof. rises, upwards. The board rests. on
brackets F placed at the four angles of the box, the cover C. being previously
removed; G is the lid or cover of the box, which should. be kept shut;
excepting when the plate is taken out: for examination; H, I, are small
rods at the four corners of the inclined lining K of the box to support the.
cover C; J represents a disc or sieve of wire or other gauze, which is to be

page_text: placed over the cup in order to equalize the dispersion of the evaporation of
the iodine; it serves also to prevent, in case the box should be closed too
rapidly, the compressed air from driving out of the cup particles of iodine
which might adhere to the plate and cause spots on the drawing; K is the
wooden lining, formed with inclined sides in the shape of a square funnel.
This shape assists to diffuse equally the vapours of iodine which spread
as they rise.
.
.
Fig. 3 represents a magazine box or case and its cover, in which may
be enclosed the plates or surfaces before and after the drawings have been
taken. The plates are introduced into and secured by small grooves in the
insides, so that they cannot rub against one another, they being at the same
time preserved from dust. By pasting strips of paper on the junctions of the
cover and box they may be preserved from all injurious vapours, but this
is requisite only for plates or drawings completely finished, or in case the box
should not close well.
Plate 3: This plate represents four different views of the frame which
receives the thin board carrying the plate or silver surface, and serves to
preserve it from the effect of light as soon as it has received the coating
of iodine in the box, shewn in plate 2. Fig. 1 is an edge view; Fig. 2,
a front view, shewing the covers or doors to shade the silver surface; Fig. 3 is
a section, shewing the doors in the position they will be in when the plate
is exposed to the action of the light in the camera; Fig. 4 is a view of the
back side, the reverse of Fig. 2. A, A, are semicircular pieces for opening the
doors B whenever this frame with the plate is placed in the camera obscura;
C is the thin board on which is fixed the plate; D, D, are buttons on both
sides of the frame to fasten the board; and the doors E shews the thickness of
the frame; F is the plate or surface intended to receive the picture. Fig. 3
represents the frame with the doors open, as they are at the time when
a tracing is taken in the camera obscura.
The camera obscura process.-Plate 4, Fig. 1, is a vertical section, taken
through a camera obscura adapted for the process of daguerreotype or photo-
genic delineation, furnished with a frame for carrying the plate of ground glass A.
The distance this glass plate is to be from the object glass or lens is the same
as the distance at which the surface intended to receive the image is placed,
with the frame and shading doors, as shewn in C, Fig. 2, which Figure is
a horizontal section of the camera obscura. B is a mirror for observing the
effect of objects and selecting points of view; this mirror serves to enable the
operator to choose the scenery the image of which is to be reproduced; it
should be inclined about forty-five degrees to the horizon by means of. the rod

page_text: L. In order to bring the objects precisely in the focus, the ground glass should
be completely exposed, and the objects looked at as reflected on the ground
glass. The image of the objects is easily brought into the proper focus by
moving forward or backward the sliding box D, taking hold of it at the bottom
with both hands by the projections E, Fig. 2, and forcing it to or from the
operator. When the focus is properly adjusted, the thumb screw H is turned
to fix the parts in this position. The mirror is kept closed by means of two
hooks at F, which take into small eyes at G; the frame and ground glass plate
is withdrawn, and in its place is substituted the frame carrying the prepared
plate or surface, which is so represented in Fig. 2, with the shading doors B
open in the camera obscura. These doors should be internally lined with
black velvet as well as the sliding box D; to avoid all reflection of light
the object glass is achromatic and periscopic; the concave part must be
outside of the camera obscura, its diameter is about three and a half inches, and
its focus about thirteen inches. A diaphragm is placed before the object glass
at a distance of about three and a half inches, and its aperture may be closed
by means of a plate on a pivot. This camera obscura reverses the objects from
right to left, which is not of much consequence in a great number of cases;
but if it is desired to have an image, or drawing, or tracing in the natural
position of the object, a flat looking glass or mirror is to be placed on the
outside beyond the aperture of the diaphragm, as at K to J, Fig. 2, it being
fixed by means of a screw at K; but as this arrangement of reflexion
occasions a loss of light, and injures the photogenic process, therefore about
one third more time must be allowed to obtain a tracing or drawing.
. The mercurial process.-Plate 5 represents the apparatus in three different
views. Fig. 1 is a vertical section of the apparatus; Fig. 2, front elevation;
and Fig. 3 is a side view, shewing the thermometer. A is the cover of
the apparatus; B, the black board with grooves to receive the board
H carrying the silver surface or metallic plate; C, the cup containing the
mercury or quicksilver; D is the spirit lamp; E is a small cock through
which the mercury may be withdrawn, the apparatus being inclined on one side
for that purpose; F is the thermometer; G is a glass window through which
the progress on the silver surface may be inspected; II is the board carrying
the metallic plate which has received the image or design; I is a stand
or support for the spirit lamp held by the ring K, so that its flame may play
on the centre of the cup. All the interior parts of this apparatus ought to be
blackened and varnished.
The washing apparatus.-Plate 6, Fig. 1, represents a funnel lined with
blotting paper, in order to filter the solution of water and sea salt, or the
"

page_text: solution of hyposulphite of soda; Fig. 2 is a plan view of one of the troughs,
made of copper tinned; in the bottom of this is represented the plate B with
a drawing on it; two such troughs are required, one for the salt water and one
for the pure water. Fig. 2 bis is a side view of one of them; Fig. 3 represents
a small hook of copper tinned, which serves to raise the plate in the basins, to
agitate it, and to draw it out more easily; Fig. 4 is a front representation of
the washing apparatus, made of tin varnished. To wash the designs on the
plates they are placed on the stand or angular ledge D; E is a ledge to con-
duct the water to the receptacle C; and Fig. 4 bis is a side elevation of this
washing apparatus; Fig. 5 shews the jug or vessel with a large spout or lip,
it may serve to heat the distilled water in, and to pour it on the drawing when
placed on the ledge D, as seen at B, Fig. 4.
In witness whereof, I, the said Miles Berry, have hereunto set my hand
and seal, this Fourteenth day of February, One thousand eight hundred