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Tho Optioal Magio Lantern Journal and Photographic Enlarer.
77
We will suppose twelve plates to have been placed in the grooved reservoir; let us then understand the method by which these, or indeed any particular one, is brought into position for exposure, and subsequently returned to its place. Say, for instance, it is desired to expose plate No. 7,
the indicator at bottom of camera (underneath) ;
is set at that figure (see A, Fig. 2). the exposing plane E, Fig. 1, so that the grooves with which it is furnished are in exact line with those of No. 7 of the radial reservoir.
The camera is now slightly tilted, which would cause the plate to slide from its place into the exposing plane, but to avoid the possibility of the plate going backwards or forwards at random, it 1s prevented from sliding into place until a spring catch, closing the opening of focussing plane, is liberated. This is effected by a very slight turn of the milled head on the top of camera (see H, Fig. 1). Immediately the knob is liberated the plate is locked in position.
Fic. 2,
Thearm A, Fig. 2, is then pointed to the words “to expose.” The particular plate is now opposite the lens ready for exposure, after which it is returned to its receptacle by turning A to 7, inclining the camera, and touching the spring H. The whole movement described being effected in a few seconds. “55
The lens of the camera is a rapid rectilinear, with rotating diaphragm, and is provided with
J Fia. 3.
an excellent shutter, Fig. 3, placed immediately in front. The terminals of the two cords for
This turns |
!
setting and releasing the shutter are shown at K and J, Fig. 2.
This shutter can be used at varying speeds by adjusting the screw L, and for time exposures the lens can be left open by pulling the cord J until one click is heard. It is closed by a touch on K.
Referring to Fig. 2,a pointer C will be seen, also a scale D, representing in yards the required position at which the pointer may be: set for focussing any particular object.
Horizontal and vertical finders are fitted, and the particular camera which we have is ebonised mahogany, quarter-plate size, but the sarne instrument is also made for half-plate and lantern size.
After carefully examining the camera inside and out, one cannot help noticing how strongly and neatly it is made. Climatic influence should have no effect upon such an excellent instrument.
20:
An Amateur Saturator and Jet. By CLERICUS.
|; INcomplying withthe Editor’s invitation to give
a few particulars of the above, I must premise that I have nothing striking or original to offer. Experts will no doubt discover much that is.
| open to criticism. Even amateurs, for whom I
write, may very likely be able to modify some of the details with advantage. I wish simply tc. show that with ordinary appliances, and at a very small cost, an apparatus may be made, which, having been found useful by myself, I believe others will be glad to possess.
The Saturator.—The construction is shown by Fig. 1, which requires but little explanation.
Fic, 1,
Fic,'2,
The main part is formed of two brass tubes (aia) 2in.in diameter and 12in. long. Into each end of these is soldered a disc of brass with an opening in the middle to admit the smaller