Nitrate of silver 30 grains.
Glacial acetic acid 1 drachm.
Distilled water[7] 1 ounce.
If the weather is warm, 6 drops of gallic acid to the 10 of aceto-nitrate
will suffice, and enable the prepared excited paper to be kept longer.
This exciting fluid may be applied either directly {599} by means of the
glass rod, or by floating, as before, and then the glass rod. But if
floating is resorted to, then a larger quantity must be prepared. As soon
as it is applied the paper should be blotted off by means of blotting-paper
(which should never be used more than once in this way, although preserved
for other purposes), and put into the dark frames for use.[8] It is not
requisite that the paper should be perfectly dry. This exciting should be
conducted by a very feeble light; the paper is much more sensitive than is
generally supposed; in fact, it is then in a state to print from by the aid
of gas or the light of a common lamp, and very agreeable positives are so
produced by this negative mode of printing.
I would advise the aceto-nitrate of silver and the solution of gallic acid
to be kept in two bottles with wooden cases differing in their shape, so
that they may not be mistaken when operating, in comparative darkness. A
1/4 of an ounce of gallic acid put into such a 3-ounce bottle, and _quite_
filled up with distilled water as often as any is used, will serve a very
long time.
I would also recommend that the paper should be excited upon the morning of
the day upon which it is intended to be used; no doubt the longer it is
kept, the less active and less certain it becomes. I have, however, used it
successfully eight days after excitement, and have a good negative produced
at that length of time. The general medium time of exposure required is
five minutes. In the negatives exhibited, the time has varied from three
minutes to eight, the latter being when the day was very dull.
The pictures should be developed by equal quantities of the aceto-nitrate
of silver and the saturated solution of gallic acid, which are to be mixed
and immediately applied to the exposed surface. This may be done several
hours after the pictures have been removed from the camera. Care should be
taken that the back of the picture does not become wetted, as this is apt
to produce a stain which may spoil the printing of the positive.
If upon the removal of the paper from the dark frame, the picture is very
apparent, by first applying little gallic acid, and immediately afterwards
the _mixed_ solutions, less likelihood is incurred of staining the
negative, which will be more evenly and intensely developed. If a browning
take place, a few drops of strong acetic acid will generally check it.
Should the picture be very tardy, either from an insufficient exposure,
want of light, or other cause, a few drops of a solution of pyrogallic
acid, made with 3 grains to the ounce of water, and a drachm of acetic
acid, will act very beneficially. It sometimes gives an unpleasant redness
upon the surface, but produces great intensity upon looking through it.
Until the pyrogallic solution was added, there was scarcely anything
visible upon the specimen exhibited, the failure having in the _first_
instance happened from the badness of the iodized paper.
As soon as the picture is sufficiently developed it should be placed in
water, which should be changed once or twice; after soaking for a short
time, say half an hour, it may be pinned up and dried, or it may at once be
placed in a solution almost saturated, or quite so, of hyposulphite of
soda, remaining there no longer than is needful for the entire removal of
the iodide, which is known by the disappearance of the yellow colour.
When travelling it is often desirable to avoid using the hyposulphite, for
many reasons (besides that of getting rid of extra chemicals), and it may
be relied on that negatives will keep even under exposure to light for a
very long time. I have kept some for several weeks, and I believe Mr.
Rosling has kept them for some months.
The hyposulphite, lastly, should be effectually removed from the negative
by soaking in water, which should be frequently changed.
Some prefer to use the hypo, quite hot, or even boiling, as thereby the
size of the paper is removed, allowing of its being afterwards readily
waxed.[9] I have always found that pouring a little boiling water upon the
paper effectually accomplishes the object; some negatives will readily wax
even when the size is not removed. A box iron very hot is best for the
purpose; but the most important thing to attend to is that the paper should
be perfectly dry, and it should therefore be passed between blotting-paper
and well ironed before the wax is applied. Negatives will even attract
moisture from the atmosphere, and therefore this process should at all
times be resorted to immediately before the application of the wax.
Some photographers prefer, instead of using wax, to apply a solution of
Canada balsam in spirits of turpentine. This certainly adds much to the
transparency of the negative; and, in some instances, may be very
desirable. Even in so simple a thing as white wax, there is much {600}
variety; some forming little flocculent appearances on the paper, which is
not the case with other samples. Probably it may be adulterated with
stearine, and other substances producing this difference.
Before concluding these remarks, I would draw attention to the great
convenience of the use of a bag of yellow calico, made so large as to
entirely cover the head and shoulders, and confined round the waist by
means of a stout elastic band. It was first, I believe, used by Dr.
Mansell. In a recent excursion, I have, with the greatest ease, been
enabled to change all my papers without any detriment whatever, and thereby
dispensed with the weight of more than a single paper-holder. The bag is no
inconvenience, and answers perfectly well, at any residence you may chance
upon, to obstruct the light of the window, if not protected with shutters.
I would also beg to mention that a certain portion of the bromide of silver
introduced into the iodized paper seems much to accelerate its power of
receiving the green colour, as it undoubtedly does in the collodion.
Although it does not accelerate its _general_ action, it is decidedly a
great advantage for foliage. Its best proportions I have not been able
accurately to determine; but I believe if the following quantity is added
to the portion of solution of iodide of silver above recommended to be
made, that it will approach very near to that which will prove to be the
most desirable. Dissolve separately thirty grains of bromide of potassium,
and 42 grains of nitrate of silver, in separate half-ounces of distilled
water; mix, stir well, and wash the precipitate; pour upon it, in a glass
measure, distilled water up to one ounce; then, upon the addition of 245
grains of iodide of potassium, a clear solution will be obtained; should it
not, a few more grains of the iodide of potassium will effect it. It may be
well to add that I believe neither of the solutions is injured by keeping,
especially if preserved in the dark.
I would here offer a caution against too great reliance being placed upon
the use of gutta-percha vessels when travelling, as during the past summer
I had a bottle containing distilled water which came into pieces; and I
have now a new gutta-percha tray which has separated from its sides. This
may appear trivial, but when away from home the greatest inconvenience
results from these things, which may be easily avoided.[10]
Dishes of zinc painted or japanned on the interior surface answer better
than gutta-percha, and one inverted within another forms, when travelling,
an admirable lid-box for the protection of glass bottles, rods, &c. On the
Continent wooden dishes coated with shellac varnish are almost entirely
used.
[Footnote 2: In a communication I formerly addressed to my friend the
Editor of "N. & Q.," one of the arguments I used in favour of the collodion
process was, that the operator was enabled at once to know the results of
his attempts; and was not left in suspense concerning the probable success,
as with a paper picture requiring an after development.
I made that observation not only from the partial success which had then
attended my own manipulations, but from the degree of success which was
attained by the majority of my photographic friends. But that objection is
now almost entirely removed by the comparative certainty to which the paper
process is reduced.]
[Footnote 3: The effect was illustrated in two negatives of the same
subject, taken at the same time, exhibited to the meeting, and which may
now be seen at Mr. Bell's by those who take an interest in the subject.]
[Footnote 4: For this purpose, strips of wood from 1 inch to 1-1/2 square
will be found much more convenient to pin the paper to than the tape or
string usually recommended. The pressure of a corner of the paper to the
wood will render it almost sufficiently adherent without the pin, and do
away with the vexation of corners tearing off.]
[Footnote 5: Some difference of opinion seemed to exist at the reading of
the paper, as to the propriety of preparing iodized paper long before it
was required for use, and I have since received some letters from very able
photographers who have attributed an occasional want of success to this
cause. I have, however, never myself seen good iodized paper deteriorated
by age. Many friends tell me they have used it when several years old; and
I can confirm this by a remarkable instance. On Tuesday (Dec. 6) I was
successful in obtaining a perfectly good negative in the usual time from
some paper kindly presented to me by Mr. Mackinly, and which has been in
his possession since the year 1844. I should add, the paper bears the mark
of "J. Whatman, 1842," and has all the characters of Turner's best
photographic paper. It appears to be a make of Whatman's paper which I have
not hitherto seen, and, from its date, was evidently not made for
photographic purposes.]
[Footnote 6: The paper may be iodized by pouring over it 30 minims of the
iodizing solution, and then smoothing it over with the glass rod. Care must
however be taken not to wet the back of the paper, as an unevenness of
depth in the negative would probably be the result.]
[Footnote 7: Much more attention should be paid to the purity of the
distilled water than is generally supposed. In the many processes in which
distilled water is used, there is none in which attention to this is so
much required as the calotype process. I mention this from having lately
had some otherwise fine negatives spoiled by being covered with spots,
emanating entirely from impurities in distilled water purchased by me
during a late excursion into the country.]
[Footnote 8: It is very requisite that the glasses of the frames should be
thoroughly cleansed before the excited papers are put into them. Although
not perceptible to the eye, there is often left on the glass (if this
precaution is not used) a decomposing influence which afterwards shows
itself by stains upon the negative.]
[Footnote 9: If boiling water is carefully poured in the negative in a
porcelain dish, it will frequently remove a great deal of colouring matter,
thereby rendering the negative still more translucent. It is astonishing
how much colouring matter a negative so treated will give out, even when to
the eye it appears so clean as not to require it.]
[Footnote 10: MR. SHADBOLT suggested a remedy for the disasters referred to
by DR. DIAMOND with regard to the gutta-percha vessels. Gutta-percha is
perfectly soluble in chloroform. MR. SHADBOLT therefore showed that if the
operator carries a small bottle of chloroform with him, he would be able to
mend the gutta-percha at any moment in a few seconds. It was not necessary
that the bottle should hold above half an ounce of chloroform.]
* * * * *
Replies to Minor Queries.
_Belike_ (Vol. viii., p. 358.).--The reasoning by which H. C. K. supports
his conjecture that "belike" in _Macbeth_ is formed immediately by
prefixing _be_ to a supposed verb, _like_, to lie, is ingenious, but far
from satisfactory. In the first place, we never used _to like_ in the sense
of _to lie_, the nearest approach to it is _to lig_. And in the next place,
the verb to _like_, to please, to feel or cause pleasure, to approve or
regard with approbation, as a consequential usage (agreeably to the Dutch
form of Liicken (Kilian), to _assimilate_), is common from our earliest
writers. Instances from Robert of Gloucester, Chaucer, and North, with
instances also of _mislike_, to displease, may be found in Richardson and
others in Todd's _Johnson_.
Now, when we have a word well established in various usage (as _like_,
similis), from which other usages may be easily deduced, why not adopt that
word as the immediate source, rather than seek for a new one? That _like_,
now written _ly_, is from _lic_, a corpse, _i.e._ an essence, has, I
believe, the merit of originality; so too, his notion that _corpse_ is an
_essence_, and the more, as emanating from a rectory, which probably is not
far removed frown a churchyard.
H. C. K., it is very _likely_, is right in his conception that all his
three _likes_ "have had originally one and the same source;" but he does
not appear inclined to rest contented with the very sufficient one in our
parent language, suggested by Richardson (in his 8vo. dictionary), the
Gothic _lag-yan_; A.-S. _lec-gan_, or _lic-gan_, to lay or lie.
I should interpret _belike_ (for so I should write it with H. C. K.) by
"approve."