American Hand Book of the Daguerreotype Part 11

[From Humphrey's Journal, vol. ii 1851]

As a general thing, however perfect any invention may be deemed by the inventor or discoverer, it falls to the lot of most, to be the subject of improvement and advancement, and especially is this the case with those new projects in science which open an untrodden field to the view of the artisan. Such has been, in an eminent degree, the case with the discovery first announced to the world by Mons. Jean Jaques Claude Daguerre, of Paris, in the year 1839, and which excited unbounded astonishment, curiosity and surprise. It may be questioned had any other than Daguerre himself discovered a like beautiful combination, whether the world would have been favored with details exhibiting so much care, patience and perseverance as the Daguerreotype on its introduction. Shortly after, these details reached the United States, by Professor S. F. B. Morse, of New York, who was, at the time of the discovery, residing in Paris. By this announcement, the whole scientific corps was set in operation, many repeating the experiments, following carefully the directions pointed out by Daguerre, as being necessary to success. Among the number in the United States, was Alexander S. Wolcott (since deceased) and myself; both of this city.

On the morning of the 6th day of October, 1839, I took to A. Wolcott's residence, a full description of Daguerre's discovery, he being at the time engaged in the department of Mechanical Dentistry, on some work requiring his immediate attention, the work being promised at 2 P.M.

that day; having, therefore, no opportunity to read the description for himself (a thing he was accustomed to do at all times, when investigating any subject). I read to him the paper, and proposed to him that if he would plan a camera (a matter he was fully acquainted with, both theoretically and practically), I would obtain the materials as specified by Daguerre. This being agreed to, I departed for the purpose, and on my return to his shop, he handed me the sketch of a camera box, without at all explaining in what manner the lens was to be mounted. This I also undertook to procure. After 2, P.M., he had more leisure, when he proceeded to complete the camera, introducing for that purpose a reflector in the back of the box, and also to affix a plate holder on the inside, with a slide to obtain the focus on the plate, prepared after the manner of Daguerre. While Mr. Wolcott was engaged with the camera, I busied myself in polis.h.i.+ng the silver plate, or rather silver plated copper; but ere reaching the end preparatory to iodizing, I found I had nearly or quite removed the silver surface from off the plate, and that being the best piece of sliver-plated copper to be found, the first remedy at hand that suggested itself, was a burnisher, and a few strips were quickly burnished and polished.

Meantime, the camera being finished, Mr. Wolcott, after reading for himself Daguerre's method of iodizing, prepared two plates, and placing them in the camera, guessed at the required time they should remain exposed to the action of the light; after mercurializing each in turn, and removing the iodized surface with a solution of common salt two successful impressions were obtained, each unlike the other!

Considerable surprise was excited by this result, for each plate was managed precisely like the other. On referring to Daguerre, no explanation was found for this strange result; time, however, revealed to us that one picture was positive, and the other negative. On this subject I shall have much to say during the progress of the work.

Investigating, the cause of this difference occupied the remainder of that day. However, another attempt was agreed upon, and the instruments, plates, etc., prepared and taken up into an attic room, in a position most favorable for light. Having duly arranged the camera, I sat for five minutes, and the result was a profile miniature (a miniature in reality,) or a plate not quite three-eighths of an inch square. Thus, with much deliberation and study, pa.s.sed the first day in Daguerreotype--little dreaming or knowing into what a labyrinth such a beginning was hastening us.

[Description of apparatus represented on pages 192 and 199:]

A.--The Box--about 4 inches long by about 2 outside diameter.

B.--The Reflector soldered to a bra.s.s screw, and mounted in the rear of the box.

c.--The slide to regulate the focus to the plate holder.

d.--The standard to the plate holder screwed to the slide.

f.--The plate-holder frame having two small ledges, * *, for the plate to rest upon.

{192}

g.--The plate resting upon the ledge., * *, and kept against the frame by the spring h. The plates used were about 3/8 of an inch square.

A.--The window with the sashes removed.

B and C (p. 199) are large looking-gla.s.ses mounted as plain reflectors, the lower one C having rotary motion upon the saddle, resting upon the sill of the window in order to direct the rays of the sun upon the reflector B, at any hour of the day--the vertical motion of the reflector C being necessary, the sun varying in alt.i.tude so much during the hours most favorable to the production of portraits. The reflector C was {193} kept up to the required position by the handle lever, upright post and bolts. Reflector B was hinged at its upper end at the top of the window frame, the only motion being necessary was that which would reflect upon the sitter the incident rays from reflector C--the reflector B being kept at the required angle by the connecting lever m, etc. Suitable back-grounds were placed behind the sitter.

[Ill.u.s.tration: Fig. 12 (amdg_12.gif)]

The reflector B and C, had frequently to be renewed, the heat of the sun soon destroying their brilliance or power of reflecting, light, before renewing them, however, we resorted to the springing of them, by which means their power was increased for a period.

The camera or reflecting apparatus, invented by Mr. Wolcott, was, from the nature of the case, better adapted at that day to the taking of portraits from life, than any other instruments. After carefully examining the camera described by Daguerre, and the time stated as necessary to produce action for an image, it became evident to the mind of Mr. Wolcott at once, that more light could be obtained (as the field of view required was not large) by employing a reflector of short focus and wide aperture, than from a lens arrangement, owing to spherical aberration and other causes. Many experiments having been tried with the small instrument figured (p. 199), a reflector for taking portraits from life was determined on, having eight inches diameter, with twelve inches focal distance for parallel rays; this was to admit plates of two inches wide by two and a half long Mr. Wolcott having on hand reflectors of the right diameter, for Newtonian telescopes, of eight feet focal distance, resolved (as it was a matter of experiment) to grind down or increase the curve for the focal distance before named--this required time. In the mean time, many plans were pursued for making good plates, and the means of finis.h.i.+ng, them. As the completion of the large reflector drew to a close, our mutual friend, Henry Fitz, Jr., returned from England, whither he had been on a visit, and when he heard what we were about, kindly offered his a.s.sistance; he being well versed in optics, and having been before engaged with Mr.

Wolcott, in that and other business is offer was gladly accepted--Mr.

Wolcott himself having frequent engagement; to fill as operator in the details of mechanical dentistry. Thus, by the aid of Mr. Fitz, the reflector was polished, and experiments soon after tried on plates of two by tow and a half inches, with tolerable success. Illness on my part quite suspended further trial for nearly four weeks.

On my recovery, early in January, 1840, our experiments were again resumed with improved results, so much so as to induce Mr. Wolcott and myself to entertain serious thoughts of making a business of the taking of likenesses from life, intending to use the reflecting apparatus invented by Mr. Wolcott, and for which he obtained Letters Patent, on the 8th day of May, 1840. Up to January 1st, 1840, all experiments had been tried on an economical scale, and the apparatus then made, was unfit for public exhibition; we resolved to make the instruments as perfect as possible while they were in progress of manufacture.

Experiments were made upon mediums for protecting the eyes from the direct light of the sun, and also upon the best form and material for a back-ground to the likenesses. The length of time required for a "sitting," even with the reflecting apparatus, was such as to render the operation anything but pleasant. Expedients were ever ready in the hands of Wolcott: blue gla.s.s was tried and abandoned in consequence of being, at that time, unable to procure a piece of uniform density and surface: afterwards a series of thin muslin screens secured to wire frames were prepared as a subst.i.tute for blue gla.s.s. The objections to these screens, however, were serious, inasmuch as a multiplication of them became necessary to lessen the intensity of the light sufficiently for due protection to the eyes, without which, the likenesses, other than profiles, were very unpleasant to look upon. Most of the portraits, then of necessity were profiles formed upon back-grounds, the lighter parts relieved upon black, and the darker parts upon light ground; the back-ground proper being of light colored material with black velvet so disposed upon the light ground, this being placed sufficiently far from the sitter, to produce harmony of effect when viewed in the field of the camera. Other difficulties presented themselves seriously to the working of the discovery of Daguerre, to portrait taking--one of which was the necessity for a constant and nearly horizontal light, that the shaded portions of the portrait should not be too hard, and yet, at the same time, be sufficiently well developed without the "high light" of the picture becoming overdone, solarized or destroyed. In almost all the early specimens of the Daguerreotype, extremes of light and shade presented themselves, much to the annoyance of the early operators, and seriously objectionable were such portraits. To overcome this difficulty, Mr. Wolcott mounted, with suitable joints, upon the top of his camera, a large looking-gla.s.s or plane reflector, in such a manner that the light of the sun (as a strong light was absolutely necessary), when falling upon the gla.s.s could be directed upon the person in an almost horizontal direction.

Early in February, 1840, Mr. Johnson, Sen., (since deceased) sailed for Europe with a few specimen likenesses taken with the instruments completed as above, with the intention of patenting the invention. On his arrival a joint arrangement was effected with Mr. Richard Beard, of London, in patenting and working the invention in England. Up to February, 1840, but few friends had been made acquainted with the progress of the art in the hands of Mr. Wolcott and myself. From time to time reports reached us from various sources of the success of others, and specimens of landscapes, etc., were exhibited at Dr. James R. Chilton's laboratory, in Broadway, much to the gratification of the numerous visitors and anxious expectants for this most wonderful discovery. Dr. Chilton, Professor J. J. Mapes, Professor J. W. Draper.

Professor S. F. B. Morse, all of this city; Mr. Cornelius, Dr. G.o.ddard and others of Philadelphia; Mr. Southworth, Professor Plumbe, and numerous others were early in the field; all, however, using the same description of camera as that of Daguerre, with modification for light, either by enlargement by lens and aperture for light, or by shortening the focal distance.

At a conversational meeting of the Mechanics' Inst.i.tute, Professor J.

J. Mapes being present, a question was asked if any one present could give information relative to portraiture from life by the Daguerreotype. Mr. Kells, a friend of Mr. Wolcott and a scientific and practical man (since deceased), at once marked out upon the black-board, the whole as contrived by Mr. Wolcott. This gave publicity to the invention of Mr. Wolcott. Shortly after, Professor Mapes, Dr. Chilton, and many others, sat for their portraits, and were highly gratified. Professor Morse also came and proposed to Mr.

Wolcott to join him in the working of the invention, etc.

From this time much interest was manifested by our friends in our progress. Rooms were obtained in the Granite Buildings, corner of Broadway and Chambers street, and fitted for business. The rooms being small, it was soon found impracticable to use the arrangement of looking-gla.s.s, as previously spoken of; a new plan became necessary, to introduce which, the sashes were removed, {199} and two large looking-gla.s.ses were mounted in proper frames, thus:--

[Ill.u.s.tration: Fig. 13 (amdg_13.gif)]

Just in front, and between the sitter and {200} the reflector, upon a proper stand, were used those paper muslin screen before described; also screens of tissue paper. These screens, however, when they were used, required so much time for a sitting, that some other medium, as a protection to the eyes, became absolutely necessary. The most plausible thing that suggested itself was blue gla.s.s; but, as this could not be found, numerous were the expedients proposed by the friends of the art, who from time to time visited our rooms. At the suggestion of Professor Mapes (who is ever ready to a.s.sist those in perplexity), a trough of plate gla.s.s s, about twenty-eight inches square in the clear, and from three to four inches thick, was filled with a solution of ammonia sulphate of copper, and mounted on the frame as in the sketch, which, for a time, answered extremely well; soon, however, decomposition of this solution became apparent from the increased length of time required for a sitting, although to the eye of an observer, no visible cause for such long sittings could be pointed out. Professor Mapes being appealed to, suggested that to the above solution a little acid be added which acted like a charm--shortening the time for a sitting from six, eight, or ten minutes to that of about one. Decomposition, however, would go on by the action of light and heat through the solution. New solutions were tried, when the whole were finally abandoned as being, too uncertain and troublesome. (The reflecting apparatus R, was placed upon the stand as in the sketch, with a wedge for elevating the camera, between it and the table, to obtain the image properly upon the plate.) A quant.i.ty of blue window gla.s.s was next obtained, and holes drilled through the corners of it, and several sheets were wired together to increase the size, and, when complete, was suspended from the ceiling in its proper place, and so arranged that when a person was sitting, this sheet of gla.s.s could be moved to and from, the object of which was to prevent shadows on the face of the sitter produced from the uneven surface of the gla.s.s. This latter contrivance was used until a perfect plate of gla.s.s was procured.

The number of persons desirous of obtaining, their miniatures, induced many to entertain the idea of establis.h.i.+ng themselves in the Art as a profession, and numerous were the applications for information; many persons paying for their portraits solely with the view of seeing the manner of our manipulations, in order that they might obtain information to carry on likeness-taking as a business.

The reflecting camera being a very troublesome instrument to make, and difficulties besetting us from every source, but little attention could be given to teaching others; and, indeed, as the facts seemed to be at this time, we knew but little of the necessary manipulations ourselves.

In course of time, several established themselves. The first one, after ourselves, who worked the discovery of Daguerre for portrait taking in this city, was a Mr. Prosch; followed soon after by many others, in almost all cases copying the reflecting arrangement for light, as figured above, many using it even after we had long abandoned that arrangement for a better one.

Innumerable obstacles to the rapid advance of the daguerreotype, presented themselves almost hourly, much to the annoyance of ourselves, and those dependent upon our movements for their advancement. Among the most difficult problems of the day, was the procuring of good plates. Messrs. Corduran & Co. were among the first to supply the trade; at that early day, however, it was a very rare thing, to be able to procure an even perfect surface, from the fact that a pure surface of silver could scarcely be obtained, the manufacturers deeming it too much trouble to prepare silver plated copper with pure silver--the result was, that in attempting to polish perfectly such plated metal as could be procured, the plates would become cloudy, or colored in spots, from the fact of having more or less alloy, according as more or less of the silver surface was removed in polis.h.i.+ng the plate fit for an impression. To explain more clearly, it was the practice of most silver platers to use an alloy for silver-plating. In the reduction of the ingot to sheet metal, annealing has to be resorted to, and acid pickles to remove oxides, etc. The number of times the plated metal is exposed to heat and acid in its reduction to the required thickness, produces a surface of pure silver. The most of this surface is, however, so rough as to be with difficulty polished, without in places removing entirely this pellicle of pure metal, and exposing a polished surface of the alloy used in plating. Whenever such metal was used, very unsightly stains or spots frequently disfigured the portraits.

The portrait, or portion of it, developed upon the pure silver, being much lighter or whiter than that developed upon the alloy; it therefore appeared that the purer the silver, the more sensitive the plate became. Accordingly, we directed Messrs. Scovills, of Connecticut, to prepare a roll of silver-plated metal, with pure silver; it fortunately proved to be a good article, but, unfortunately, a pound of this metal (early in 1840) cost the round sum of $9. Like descriptions of metal, the same gentlemen would be glad to furnish, at this time, for $4. Soon after this, some samples of English plated metal, of a very superior quality, came to our possession, and relieved us from the toil of making and plating one plate at a time, an expedient we were compelled to resort to, to command material to meet the pressing demands for portraits.

Having it now in our power to obtain good plated metal, a more rapid mode of polis.h.i.+ng than that recommended by Daguerre was attempted as follows:

This metal was cut to the desired size, and having a pair of "hand rolls" at hand, each plate, with its silvered side placed next to the highly polished surface of a steel die, was pa.s.sed and repa.s.sed through the rolls many times, by which process a very smooth, perfect surface was obtained. The plates were then annealed, and a number of plates thus prepared were fastened to the bottom of a box a few inches deep a foot wide, and eighteen inches long; this box was placed upon a table and attached to a rod connected to the face plate of a lathe, a few inches from its centre, so as to give the box a reciprocating motion.

A quant.i.ty of emery was now strewn over the plates, and the lathe set in motion. The action produced wag a friction or rubbing of the emery over the surface of the plates.

When continued for some time, a greyish polish was the result.

Linseed, when used in the same manner, gave us better hope of success, and the next step resorted to was to build a wheel and suspend it after the manner of a grindstone. The plates being secured to the inner side of the wheel or case, and as this case revolved, the seeds would constantly keep to the lower level, and their sliding over the surface of the plates would polish or burnish their surfaces. This, with the former, was soon abandoned; rounded shots of silver placed in the same wheel were found not to perform the polis.h.i.+ng so well as linseed.

Buff-wheels of leather with rotten-stone and oil, proved to be far superior to all other contrivances; and, subsequently, at the suggestion of Professor Draper, velvet was used in lieu of buff leather, and soon superseded all other substances, both for lathe and hand-buffs, and I would add, for the benefit of new beginners that those who are familiar with its use, prefer cotton velvet. The only requisite necessary is, that the buffs made of cotton velvet should be kept dry and warm.

The greater number of operators, with whose practice I am familiar, use, for polis.h.i.+ng plates, prepared tripoli, imported from France, or Browne's rotten-stone. The former of these articles is very objectionable, inasmuch as there is no positive certainty of being enabled to procure or make the article of uniform grit--the nature of the substance rendering, it impossible to reduce it to varying degrees of evenness, by the well known process of was.h.i.+ng, for that purpose, and the burning of rotten-stone changes its chemical nature somewhat, at the same time rendering, this invaluable article harsh and gritty.

And especially, no reliance can be placed upon burned rotten stone if purchased from those who do not give very great attention and care to its preparation; and the same remarks apply to rouge.

The best article for polis.h.i.+ng Daguerreotype plates is rotten-stone, such as can be procured in any town, prepared after the following manner: Procure, say half a dozen wide-mouthed bottles, of suitable dimensions, numbering each from one to six. Put into No. 1 about half a pound of rotten-stone, and nearly fill the bottle with water. Then, with a proper stick or spatule, mix well the rotten-stone and water; after which, let No. 1 rest for, say one minute, then carefully pour off into bottle No. 2 (or, what would be better, draw off by a syphon) as much of the floating particles of rotten-stone as is suspended in the water. Again fill bottle No. 1 with water, agitate it as before, and decant it to bottle No. 2, care being taken to draw off only the suspended particles of rotten-stone.

When a sufficient quant.i.ty of was.h.i.+ngs from bottle No. 1 is collected into bottle No. 2, a similar process must be gone through, as above stated, for No. 1; the difference being in the care required, and in the time allowed between the stirring or mixing the rotten-stone and water. The floating particles of rotten-stone, after four minutes'

subsiding, will be found fine enough for the finest Daguerreotype polis.h.i.+ng required.

A quant.i.ty of such was.h.i.+ngs may be collected in a large bottle, and allowed to stand a few hours, when all the rotten-stone will have settled. The water may be poured off and the rotten-stone put into an evaporating dish, and while being dried, must be constantly stirred to obtain an impalpable powder.

Further was.h.i.+ngs may in like manner be resorted to for finer qualities of rotten-stone. In my practice, I have used the articles at two and four minutes' settling, and occasionally have prepared it after standing for eight minutes. So fine a quality as this, however, is seldom required. In using, rotten-stone, I mix with it, for polis.h.i.+ng, fine olive oil, until I obtain a thin paste--and the best of all methods for polis.h.i.+ng (well planished) Daguerreotype plates, is one like that used for gla.s.s by lens polishers; that is, by using a disc or buff-wheel, and having, a suitable holder by which to secure the plate, and then by pressing the plate against the revolving buff, well saturated with the mixed oil and rotten-stone, a very good surface is obtained. A quant.i.ty of plates may be prepared in this way, and all the adhering oil, etc., may be removed by a clean hand, or lathe buff, after which each plate must be heated to the point necessary to burn off the remaining oil great care being required not to overheat the plate. A very slight excess of temperature will at once destroy all the polish previously obtained. The test for ascertaining the right temperature is at hand; the adhering oil will be driven from the plate in the form of smoke when the right temperature is reached. The moment the smoke ceases to rise from the plate, the heat must be removed, and the plate quickly cooled upon a piece of iron.

A quant.i.ty of plates thus prepared may be kept on hand for any required time, and the labor of one minute, with a lathe or hand-buff with dry charcoal, or rather, prepared lampblack, will perfectly polish the surface ready for indexing, etc. This lampblack also requires some care in preparing. Take a small-size crucible, properly temper it by a slow fire, that it may not be cracked after which, fill it with common lampblack, cover it over with a piece of soap-stone, and again replace it in the fire. Build a good hard coal fire around it continue the heat for two or three hours, being careful not to raise the cover till the crucible be quite cold. Pulverize when using it. It is very desirable to keep this lampblack dry and warm. Some operators use much rouge I would recommend the above in preference; but those who feel that they cannot dispense with the use of rouge, had better try a large addition of prepared lampblack to a small one of rouge, as this latter article, unless great pains be taken in its preparation, will adhere and work itself into the body of the surface, so that it cannot be removed therefrom; and I have seen many specimens of Daguerreotype very much injured in effect from this rouge tint disseminated throughout their shaded features, at the same time that the whole general effect of such pictures is that of a want of life. It is true that with the use of rouge a very high degree of polish may be obtained, but probably not higher than can be produced with many other substances of a less objectionable nature.

From the announcement of the discovery by Daguerre to the beginning of the year 1840, I am not aware of any attempt to lessen the time for the action of an image, or an impression, other than that of the reflecting camera invented by Mr. Wolcott. Early, however, in 1840, Mr. Wolcott was desirous to be enabled to further shorten the time for a sitting, and having some knowledge of bromine and its action, by request, Dr.

Chilton prepared a small quant.i.ty; but Mr. Wolcott did not succeed very well with it, he having invariably used too much in combination with iodine to produce that sensitive coating now well known to the profession. Professor Morse, of this city, Dr. G.o.ddard, of Philadelphia, and others, in the years 1840 and 1841, were acquainted with the use of bromine. N. Griffing, of this city, or myself, used with tolerable success, iodine in large excess to nitric acid and water; and, subsequently, to nitro muriatic acid (which reacted and formed a peculiar chloride of iodine); this latter combination proved to be preferable to simple iodine, at the same time somewhat more sensitive, and was used by me in this city up to the time of my leaving for London (October 1, 1840). On arriving in London, I inst.i.tuted a series of experiments in the various chemical combinations, solely with the view to be enabled to obtain more speedily a portrait than it was practicable to do with any known chemicals at that date. The high lat.i.tude, and the winter season of the year rendering but a feeble light at best, the greater the necessity for a more sensitive chemical preparation to the shortening the time for a sitting. Near the beginning of the year 1841, I discovered and practically applied, chloride of iodine to great advantage, and, as far as memory serves me, I believe the first used in this country was some made and s.h.i.+pped, Messrs. Harnden & Co., from London, to Mr. Wolcott, in New York.

About the same time, Mr. John G.o.ddard, of London (who was a.s.sociated with myself), discovered a rather valuable combination of chemicals, consisting of a mixture of iodine, bromine, iodus, and iodic acid, and a proper combination of those bodies gave an action somewhat more sensitive than chloride of iodine--but the "high lights" of the portraits would become solarized or overdone, more frequently with this combination than with the chloride of iodine. Throughout the year 1841, I used, with great success, chloride of iodine, applied as one coating--occasionally in conjunction with Mr. Wolcott, attempting the use of iodine, bromine, and chlorine, and at times with more or less success. The difficulty of exactly combining, the three elements above mentioned, in order to produce a certainty of result with harmony of effect, was the work of many months, with great labor and study, the slightest modification requiring a long, series of practical experiments, a single change consuming, frequently, an entire day in inst.i.tuting comparisons, etc., etc.

Early in the year, 1842, I discovered a combination of chemicals (now known in London as "Wolcott's Mixture," in hermetically sealed bulbs) of exceeding uniform character, very sensitive to the action of light, and specimens produced in 1842-3, with this combination, will bear comparison with the best specimens produced at this late date.

About the same time, I discovered that however much overdone a Daguerreotype might be, the means were at hand to save or redeem it.

It has long, since been known to operators, that if a plate be exposed to light after being coated, unless it be again coated, a clear and distinct picture could not be obtained upon the same plate without first repolis.h.i.+ng and recoating the same, care being taken that no light fall upon the prepared surface. To prevent solarization, coat a plate as usual, expose to the action of light any required time (according to circ.u.mstances), say from quarter to one half more time than would be required in the ordinary method of procedure; observe, before putting the plate in the mercury box, place it over the vapor of iodine, bromine, or chlorine, etc. (carefully excluding the light), for a very brief period, great care being required to have the selected vapor very much diluted with air, in order to success. Many experiments will be required ere arriving at satisfactory results.

Specimens now unknown to general operators, for harmony of effect, have been, and may again be produced by the method pointed out above. I have found the best general effect, and the most certain result to follow from the use of the vapor of chlorine--but this requires more than ordinary care. I would, therefore, recommend the use of iodine.

Thus: to a few grains of iodine, add an ounce of warm water (which will become tinged with iodine); when cold, to half a pint of pure water in a new and clean coating box, put, of the above, fifty drops; stir and mix well this small quant.i.ty of iodine in with the water; in ten minutes this box will be ready for use. Great care and judgment will be required in the application of this vapor to the plate; if the plate remain over the vapor too long, the developed picture will have a faint and misty appearance; if not exposed long enough, the "high light" will be solarized. I have great hope of the ultimate use of this process, as it is the only means yet discovered to be enabled to secure specimens of extremes of light and shade, yet producing harmony of effect; and I would call the attention of the profession to the fact, that a plate may be exposed to the action of light for any length of time (a thousand times longer than required to act for the lesser quant.i.ty of mercury to deposit itself, or that amount necessary to form a perfect specimen), and be restored by the application of any of the vapors above mentioned, remarking that for extremes for solarization, denser vapors will be required. Much remains to be done with this discovery to the application of the Daguerreotype.

HUMPHREY'S JOURNAL OF THE DAGUERREOTYPE & PHOTOGRAPHIC ARTS.

The above-named publication is well known as the best and most valuable one devoted to the Photographic Science in this country. Humphrey's Journal made its appearance November 1st, 1850, and consequently is the first and oldest serial offered to the Photographic world.

The art of producing Portraits and Landscapes by means of Light, has recently taken a new and enlivening impulse, which will in all probability lead to important and interesting results. No practical Daguerreotypist, Photographer, or amateur, should be without the means at hand for securing all of the information upon this subject. Each should be ready to receive and apply the improvements as they may be developed. In order to accomplish this, it is a matter of great importance to the Pract.i.tioner or Experimenter that he should have a reliable medium through which he can obtain information. In what source can the inquirer better place his confidence than in a regular Journal, whose editor is literally a practical person, and familiar with the manipulations necessary for producing Portraits upon "Daguerreotype Plates," and upon gla.s.s and paper? Such is the conductor of Humphrey's Journal.