Optical projection: a treatise on the use of the lantern in exhibition and scientific demonstration (1906)

Record Details:

Title:
Optical projection: a treatise on the use of the lantern in exhibition and scientific demonstration
Date:
1906
Author:
Wright, Lewis, 1838-1905
Publisher:
London, New York, Bombay : Longmans, Green and Co.
Volume:
Optical projection: a treatise on the use of the lantern in exhibition and scientific demonstration
Leaf #:
000354
Language:
English
Collection:
Books
Format:
Books
Contributor:
University of California Libraries
Sponsor:
MSN
Coordinator:
Media History Digital Library
Description:
Date Added:
July 19, 2022
Something wrong or inaccurate about this page? Let us Know!

Thanks for helping us continually improve the quality of the Lantern search engine for all of our users! We have millions of scanned pages, so user reports are incredibly helpful for us to identify places where we can improve and update the metadata.

Please describe the issue below, and click "Submit" to send your comments to our team! If you'd prefer, you can also send us an email to mhdl@commarts.wisc.edu with your comments.




We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.

Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.

LANTERN POLARISING APPARATUS 339 FIG. 185 The other end of the elbow at B has a screw-collar, into which screws the B collar of the optical front (fig. 94), with stage, objective, and nozzle. Into this nozzle fits, so as to rotate easily, an analyser, usually a Nicol prism. The whole apparatus is shown in fig. 186, and is commonly known as the lantern polariscope, or elbow polariscope. It is also useful and convenient as a table instrument for many purposes, if a plate of finely- ground glass is fitted into the end which fits into the lantern ; and will perform in a most efficient and satisfac- tory manner all ordinary ex- periments, which do not re- quire the rotation of the polariser, at a very moderate expense. In using this instrument, it is placed on or in the flange- nozzle with the elbow lying horizontally, so that the lantern has to be deflected from the screen ; because the optical portion of the instrument must be preserved in a horizontal direction. To keep it from turning round in the flange from its own weight, there is either a slot *£ffl/ %^ fitting over a pin, ^ /sJO, or a simple bayonet joint. The Nicol prism analyser will per- form all ordinary experiments, but its performance should be examined. A Nicol of proper proportions will, with the objective described in Chapter XII., just ' cover' (i.e. give a polarised field over) slides of the standard London pattern, z2 186.—Elbow Polariscopo