Bauhaus-Universität Weimar

Optical Projection: A Treatise of the Use of the Lantern in Exhibition and Scientific Demonstration
Wright, Lewis
convenient, as a rule, to prolong the revolving base as in fig. 99, 
into a board about 9 inches wide and three feet or more in 
length, a b, while another cross-board, c d, can be slid along as 
shown in the section below the figure, so as to form a x-piece 
of the same level, at any distance from the lantern within the 
compass of a b. The use of this arrangement is very obvious. 
Suppose we are projecting the surface of a soap-film. This 
film will stand diagonally across 
a b and reflect the light to the 
screen approximately in the direc¬ 
tion of c d ; and the transverse 
board c d gives us a base on which 
to place our focussing or projecting 
lens. So of other cases in which 
the lantern has to be deflected. 
The end b of the board a b is of 
course supported by an upright 
of proper length, which may be 
hinged to it. The revolving por¬ 
tion of the stand can be quite well 
constructed of seasoned hard wood, 
if two layers are glued together 
with the grain across, and there 
will be little friction if a judicious 
use be made of black-lead. 
When work is done upon a 
table, there is one point to keep in 
mind. If it is necessary to cant up the optical beam in order 
to get a good position on the screen, it must not be done by 
canting the lantern itself, as in slide exhibitions. The whole 
table must be canted, by placing blocks under the front legs. 
Otherwise all adjustments for height will be destroyed, as 
apparatus is moved nearer to or farther from the lantern. 
The optical beam used for physical work must be parallel to 
the surface of the table. 
Fro. 100 


Sehr geehrte Benutzer,

aufgrund der aktuellen Entwicklungen in der Webtechnologie, die im Goobi viewer verwendet wird, unterstützt die Software den von Ihnen verwendeten Browser nicht mehr.

Bitte benutzen Sie einen der folgenden Browser, um diese Seite korrekt darstellen zu können.

Vielen Dank für Ihr Verständnis.