The photographic news

• Bandzählung: 29.1885
• Erscheinungsdatum: 1885
• Sprache: Englisch
• Signatur: F 135
• Vorlage: Hochschule für Grafik und Buchkunst Leipzig
• Digitalisat: Hochschule für Grafik und Buchkunst Leipzig
• Digitalisat: SLUB Dresden
• Rechtehinweis: Public Domain Mark 1.0
• URN: urn:nbn:de:bsz:14-db-id1780948042-188500006
• PURL: http://digital.slub-dresden.de/id1780948042-18850000
• OAI: oai:de:slub-dresden:db:id-1780948042-18850000
• Sammlungen: LDP: Historische Bestände der Hochschule für Grafik und Buchkunst Leipzig
• Sammlungen: Fotografie
• Bemerkung: Seite I-II fehlen in der Vorlage. Paginierfehler: Seite 160 als Seite 144 gezählt.
• Strukturtyp: Band

• Digitalisat: SLUB Dresden
• Strukturtyp: Ausgabe

estimable office to cover an address are rogues. Many do so very reasonably because it is not pleasant for Mr. A to let Mr. B know he is about changing his staff; but the just convenience of honest men unfortunately also provides a cloak for knaves. Here is an experience. The believing operator applies, sending his best specimens (which he can not now replace, being out of situation), and waits reply. Waiting results in further writing, and no reply to any letter, or redress for the robbery he is the victim of. If one goes personally to the office before writing, and asks for the name and address of advertiser, a courteous reply is given to the effect that the office address is used for secrecy, and therefore it must not be told. With such facilities for obtaining samples of work exe cuted by other hands, it is little wonder that employers bitterly complain of many men being quite incompetent to execute work in accordance with the results shown on engagement. Doubtless the question is a difficult one to both sides. Without specimens, how is an employer to judge? And yet the risk of losing valuable samples of one’s bona fde work is very galling to an operator. Personally, I am about trying a new point in this ques tion. Having lost some specimens recently, I am putting the police of a certain town on the track, and if im possible to establish a case of “ obtaining goods under false pretences,” shall try to sue on “ illegal possession ” of my property. Everyone knows that no firm of any stand ing does these tricks, and I therefore advise all assistants to be very shy of sending specimens to initials or any where before being satisfied as to the name and address of the advertiser. Our honest advertiser, who will pay to fill his show-case with good work, is an exception not often seen. Men who want specimens call them “ First-class operators,” and thus rob in the meanest and most con temptible manner real workers who foolishly trust their dishonest advertisements. I hope, sir, that in the interest of the vast number of assistants who support your valuable journal, and derive great benefit therefrom, you will be able to devise some practical means of eradicating this heartless system of perfidious robbery. I beg to enclose my card, and remain, sir, yours obediently, Agitator. [We are informed by our Publishers that in future, when undertaking the receipt of replies to advertisements, they must be entrusted with name and address for revelation to applicants in case they may deem it necessary.—Ed. P.N.] 2roceedings of Sorieties. PHOTOGRAPHIC Society of Great Britain. The monthly technical meeting was held on Tuesday last at 5a, Pall Mall East, Captain W. de W. Abney in the chair. The Chairman, after alluding to the advantages of informal meetings or social gatherings, invited Mr. Cowan to exhibit and explain his newest invention in lantern slide carriers (see p. 131); but Mr. Cowan said that the original apparatus had been taken to pieces for alteration, but that he would exhibit it at the next meeting. The conversation then turned upon the new development paper, and Mr. Warnerke gave some interesting particulars. Citrate of iron developer is, according to Warnerke, certainly equal to the oxalate, but the excess of citric acid present should not exceed 5 per cent, of the whole. Under these circumstances it is quick as oxalate. Mr. Warnerke had occasion to print 700 impressions for one negative, and he had brought the batch of prints with him. He used an ordinary printing-frame, and gave five seconds’ exposure, and he found that one complete operation with the frame could be gone through in half a minute. In twelve hours be completed three hundred prints, all but the final drying. He not only did this without help, but, in spite of many interruptions, very little variation in tone was noticeable in looking through the bulk, although some prints were a little darker than others. Mr. Warnerke had found hot rolling to give an excellent surface, but it is essential to make sure that the prints are perfectly dry. The Chairman said that he had found a highly satisfactory way to prevent adhesion to the glass when prints are squeezeed down on this material; it being merely necessary to coat the plates with negative varnish. Mr. Ince detailed his experiences on enlarging on the rapid printing paper. The Chairman exhibited some impressions made by the solar spectrum on the rapid printing paper of commerce, and the in tensity of the action in the ultra-violet region showed one sample to have been made with chloride, while another sample was as evidently prepared with bromide as a principal constituent. Some citro-chloride paper prepared by the Chairman, and which gave equally good results for printing out or by development, showed a maximum of action well inside the visible part of the spectrum, and would consequently be well adapted for working by gaslight. Mr. W. Bedford made some remarks confirming Mr. Deben- ham’s recent observations as to the influence of long develop ment on the colour of prints made by the new method (see p. 98). The exposure only controls the colour indirectly, by allowing a longer stay in a given developer. Mr. Warnerke pointed out that when prints are to be made from a weak negative, the developer should be strengthened, and vice versa. The Chairman said that his experience coincided with this view. A long conversation upon mercurial intensification then took place, in the course of which the Chairman referred to the pro tective action which varnish exercises in the case of a collodion negative intensified with mercury ; and Mr. Arnold Spiller said that he had found it advantageous to add a little hydrochloric acid to the mercuric chloride solution (see page 69). Mr. Warnerke, reverting to the subject of the rapid printing paper, said that a recently developed print could be transferred to a sheet of ordinary paper. The wet gelatine surface is pressed into contact with a sheet of dry paper, and after a short time the paper backing can be stripped off ; immersion in warm water being necessary in some instances. London and Provincial Photographic Association. A meeting of this Society was held on Thursday, the 19th inst., Mr. A. L. Henderson in the chair. Mr. A. Cowan, since the previous meeting, had—with a view to test the value of perchloric acid for the purpose recommended by Mr. Debenham—made two emulsions, one of which contained a small proportion of perchloric acid. Both emulsions gave perfectly clear shadows, and the only difference he (Mr. Cowan) could find was a slight loss of sensitiveness in the batch con taining perchloric acid ; the plates registered two numbers less on the sensitometer than the other batch. Mr. J. B. B. Wellington had also tried it, and found some of the silver was precipitated ; the colour of which was reddish. The Chairman found a considerable quantity of the silver precipitated in a flocculent state, which did not redissolve when as much as an ounce of strong liquid ammonia was added ; 240 grains of nitrate being employed in the experiment. Mr. W. E. Debenham thought the slowing action spoken of by Mr. Cowan was rather due to extraneous matter than the addition of perchloric acid ; he had never found it to slow an emulsion, but rather tended the other way. He still thought the Chairman might have dissolved his precipitate had he used more ammonia. Mr. W. K. Burton said he could not say perchloric acid would prevent green fog, because in the batch he made there was no means of knowing that the fog would have been present had the acid been absent; he added 3 drops to each 100 grains of silver nitrate, and had a perfect emulsion, about the speed of ordinary commercial plates. In reply to the Chairman, he said the speed would be 18° on Warnerke’s sensitometer. The emulsion was boiled twenty minutes, and he had noticed that extreme sensitiveness was obtained with less boiling than formerly, probably owing to some change in the gelatines now used. Mr. J. Barker mentioned a case of green fog on a developed paper print, and passed round a plate badly fogged through being kept in a dark slide coated with black varnish. Mr. A. Mackie said it was possible to keep plates a long time in dark slides before development, and instanced developing