The book of lantern ; being a practical guide to the working of the optical (1888)

Record Details:

Title:
The book of lantern ; being a practical guide to the working of the optical
Date:
1888
Publisher:
London : Wyman & Sons
Volume:
The book of lantern ; being a practical guide to the working of the optical (or magic) lantern ; with full and precise directions for making and colouring lantern pictures
Leaf #:
00034
Language:
English
Collection:
Books
Format:
Books
Contributor:
University of California Libraries
Sponsor:
MSN
Coordinator:
Media History Digital Library
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.

THE BOOK OF THE LANTERN. 21 consists of a pair of plano-convex glasses mounted in one cell, with their curved surfaces all but touching one another. This form was, I believe, first introduced with the American sciopticon. It is shown at fig. 12. The other form of condenser is that devised (but not for lantern use) by Sir John Herschell, and which consists of a double FIG. 12. FIG. 13. convex lens, associated with a meniscus, the concave side of the latter being next the radiant point, as shown in fig. 13. In a good condenser we want not only quantity of light, but also good quality, and these properties can only be secured by careful attention to certain points of construction. Quantity of light is governed by size and focal length, as already pointed out, and it may be as well to indicate here the manner in which lanterns furnished with condensers of larger size than I have recommended may be made to transmit a greater amount of light by the interposition of another lens. There were at the old Poly- technic Institution some antique lanterns with 10-in. con- densers, this large size being necessary to cover the 8-in. hand-painted transparencies which were in use before photography worked a revolution in such things. Such a large condenser, of course, meant a great loss of light, as