The Optical Magic Lantern Journal (April 1897)

The Optical Magic Lantern Journal and Photographic Enlarger. 65 He must have been an apt pupil, for in 1865, when only nineteen years of age, he was elected a Fellow of the Chemical Society, and three years later, an Associate of King’s College. As his father (the late Mr. E.G. Wood) had a flourishing business as a manufacturing optician, it was not to be surprised at that the son displayed an early taste and ambition in the same line of business, to which he added the manufacture of lanterns and slides. The lantern business was, in those days, in its comparative infancy, and being in the hands of one or two firms only, great scope was open for the display of energy, and it occurred to Mr. Wood that the creation of a large stock of slides for loan purposes should meet with success, especially as at a later period he included the hiring of a stated number of slides for a certain yearly subscription. This original idea on the part of Mr. Wood has now become so necessary to lanternists, that numbers of lantern dealers all over the world have since adopted it. A large part of Mr. Wood’s time during the past twenty-five years has been occupied in connection with literary work, and in addition to a variety of technical books, he has written numberless lectures in connection with sets of slides for optical projection. Several improvements in lantern apparatus owe their existence to the subject of our sketch, amongst them being the Euphaneron lantern ; a peculiar formation of spirit jet, there being no burning wick—(particulars of this excellent jet were published in our columns for May, 1893)— and which practically turned the spirit flame down according as the supply of direct oxygen was turned off; the edge-bar principle for screen frames to which he also applied the tent strut or stretcher; an efficient form of dissolver ; together with a variety of inventions in connection with the optical trade in general. We might, however, mention the now wellknown idea of connecting a lever to a lecturer’s reading lamp in order to show a red light as a signal to notify to the lantern operator the time for changing the slide on the screen. This is now so general that one might be inclined to think it dated back to the earliest days of the lantern, but this is not so, it being the invention of recent years, and is due to Mr. Wood. In addition to business matters, Mr. Wood has for several years had a good deal to do with certain offices pertaining to the Civil government, an important appointment being that of one of H.M. Lieutenants for the City of London; and among the offices he holds, and has held, we may mention that of Member of Commissioners of Sewers, Member of the Corporation of London, Chairman of the Guildhall School of Music, Chairman of the Guildhall Library, besides several pertaining to various philanthropical and religious institutions, in all of which he enjoys great popularity among his fellow-workers. Referring once more to his business, Mr. Wood has, for the past twenty years, kept at his premises, at 74, Cheapside (where he is assisted by one of his sons), a species of barometriclanterno-chart respecting the relation of the weather to the use of the lantern among his customers, which forms a valuable record for reference. Simple Method of Making Text Slides. ee READER sends us the following fe c suggestion, as he considers the [Ge results more satisfactory than ae methods which have been published. ey The usual method for making a slide a) 5 for a text or hymn is to make a photographic transparency; but, unfortunately, this pre-supposes a certain knowledge of photography. It is true that it has been suggested that an impression be made on gelatine from printer's type, and this film used or a support in the lantern. I find great trouble in this style owing to lack of density, besides having to wait until the ink is sufficiently dry, as the gelatine, unlike paper, has no absorbing qualities. ; What is required is that the lettering be absolutely opaque, and be ready for use without any delay. This I find can be achieved as follows :—Set the requisite wording up in type (a small fount can be obtained for a mere trifle), and ink it with what is known as printer’s varnish, which is largely composed of gold size, then make an impression on thin gelatine such as is employed in the manufacture of bon-bons. After this has been done, sprinkle a little bronze powder over the letters, and shake off the balance. It will be found that it will adhere to the varnish impressions, producing golden but absolutely opaque lettering. This, if held between the observer and the light, will appear quite black. All that remains to be done is to place the gelatine between two slide cover glasses and place it in the lantern. 5