The Optical Magic Lantern Journal (July 1900)

The Optical Magic Lantern Journal and Photographic Enlarger. 89 the reality may often be seen in the streets of any and every large town. The former depicts to us a waiter who has not had a holiday for many years, so his employer grants him one, and the morning after his day | off asks ‘‘Robert’’ how he enjoyed himself. “Bust class, sir; I didn’t know what to do with myself, so went down the city, and help’d my old friend Tomkins ‘ wash up.’ ” The reality is the proverbial ‘bus driver on his -day off, who may be seen on the box seat comparing notes with another master of the ribbons. It so happened last session that I, being ordered rest, followed in the same wake as the good folk above mentioned, by attending a course of lectures given fortnightly for some six months at one of the London literary societies. There was no more attentive member at any one of.those audiences—and they were immense —nor the talents of the various professors more ghly appreciated than by the writer of these ines. The syllabus was a highly representative one : Sir Frederick Bridge, Sir Martin Conway, Max O’Rell, Dr. Dallenger, Dr. Fison, F.R.A.S., Harry How, Dr. Conan Doyle, I. Zangwill, and many more—all good, all clever. The lantern was well to the front throughout the session, which completed a well-deserved success. But that hesitancy spoken of above—that lack of prearrangement, was painfully noticeable on several occasions. Many times the lecturers were in doubt at the finish whether to walk away or sit down, for it may be noted that in every case the platform was entirely at the speaker’s command ; that is to say, it was not cumbered by a chairman, committeeman, or in fact any one. So that any hesitancy became inexcusable. This is one of those trifling matters that does not seem worth a passing thought to the general run of lecturers, but when one sees a man quietly seat himself and wait for a vote of thanks from some one who does not appear, and when the audience are partly dispersed, he, too, thinks it time to make tracks. It was therefore by following the course adopted by the waiter and the busman that I was enabled to see some ludicrous situations at the expense of my brother lecturer, and which'I maintain sbould not be. It is only courteous, of course; to thank those who give help as volunteers ; in other words, the services of the amateur should be recognised, and that, too, in most instances publicly. But with a professional gentleman, the system, custom, orwhatever you like to call it, may well be dispensed with. There are crowds who will fail to fall into such way of thinking; well they are those who might be more particular as to what is going to be done, so that as is sometimes seen, a good lecture is sometimes marred by nonsense and blundering. Ways and rules of societies differ; find out what they are. If you want an advertisement on the cheap, signify it beforehand, and no doubt the chairman will work up the vote into a debate. The prudent lecturer, however, does not so approve. Hints and Formule. TRANSPARENCIES IN ANILINE Dyess. ONOCHROME transparencies in many of the brilliant aniline dyes can be made by the following process :— A sheet of ground glass is coated with the following sensitive preparation : Fish glue 54 grains. Isinglass <a a 1 ounce. Ammonium bichromate 25 grains. Strong ammonia 3 drops. Water 1 ounce. This is well mixed by shaking, is allowed to stand for a few hours, and the clear liquid is then drawn off. The solution so obtained keeps in good condition for about a fortnight. ‘The glass plate is thoroughly cleaned and coated whilst still wet; the excess of solution is drained off, and the plate dried and re-coated, this time draining from the opposite corner. In this way an even coating is easily obtained. The plate is exposed under a line negative, the time of exposure varying from 5 minutes in bright summer weather to 30 to 40 minutes on dull days. — The plate is first washed after exposure in cold water, wherein the still soluble parts of the film dissolve, whilst those portions which have not been protected from the negative lose their yellow colour. The image at this stage is scarcely visible. It is next soaked in a strong alcoholic solution of any desired aniline dye, in which the exposed parts assume an intense tint. Subsequent washing and drying by artificial means complete the process.—Photographische Chromk.