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New Book. Shipped from UK. Established seller since 2000. Bestandsnummer des Verkäufers LX-9781334184437
Excerpt from The Illuminating Engineer, Vol. 10: Jan. 1917 to Dec. 1917
The discussion on this subject at the last meeting of the Illuminating Engineering Society marks an important stage in our progress towards more scientific and definite methods of comparing sources of light. 'the origination of the Lumen, as a measure of flux of light, and as a basis of comparison of the illuminating power of sources is due to Professor A. Blondel, who first suggested the expression at the International Electrical Congress at Geneva in 1896. It is thus in no sense of German origin, as one of our contemporaries incautiously suggests. (in any case, the comment is irrelevant. The only points of importance are the convenience and scientific value of the term, irrespective or its origin.) In France, on the other hand, whence this unit originated, the Société Francaise de Physique passed a resolution about three years ago, advocating rating on this basis and in the United States, the Illuminating Engineering Society, which is representative of gas, electricity, and all other methods of lighting, formally adopted this method of rating at the Convention held last September. It was therefore natural that the matter should receive the attention of the Illuminating Engineering Society in this country.
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This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
Titel: The Illuminating Engineer, Vol 10 Jan 1917 ...
Verlag: Forgotten Books
Erscheinungsdatum: 2018
Einband: PAP
Zustand: New
Anbieter: Forgotten Books, London, Vereinigtes Königreich
Paperback. Zustand: New. Print on Demand. In the early 20th century, with the advent of new forms of lighting and the development of new incandescent bulbs, the concept of the 'lumen' as a measure of the total light output from a source was proposed as a replacement for candlepower, the previous standard unit. This book explores the history, use, and application of the lumen. The author presents the arguments for the lumen as a measure of luminous power, examining how it provides a better representation of the total light output of a source than candlepower. The book also explains how the lumen can be used in practical lighting calculations, including how to determine the average illumination in a room and the efficiency of lighting fixtures. This book is a reproduction of an important historical work, digitally reconstructed using state-of-the-art technology to preserve the original format. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in the book. print-on-demand item. Bestandsnummer des Verkäufers 9781334184437_0
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Anbieter: PBShop.store UK, Fairford, GLOS, Vereinigtes Königreich
PAP. Zustand: New. New Book. Shipped from UK. Established seller since 2000. Bestandsnummer des Verkäufers LW-9781334184437
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