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The Student: a magazine of theology, literature, and science
The Student a magazine of theology literature and science Author:Unknown Author Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: effect of this will be best seen by referring to fig. 1, iu which a a represents the tube of an argand burner, bb the cotton (both Fig. 1. made bug, as in t... more »he case of the ? apt ha lamp, to allow of the volatile fuel being at some distance below the flame), ? ? a ring made of perforated brass to admit a large supply of air through the oxidator, rfrf which stands upon it, reaching only just above the top of the cotton and not intersecting the flame ; ? is the button, supported by a small rod fastened in the centre of the burner ; /'the chimney, and G G the flame. Now it will be seen at once, that the flame is spread out horizontally by the button, so as to be brought just over the stream of air which rushes through the contraction of the chimney, a perfect mixture of the air with the camphine vapour being thus insured ; the large number of particles of carbon contained in a small quantity of this vapour giving rise to a very dense and bright flame. So far this'looks well for the lamp ; but when we consider that it is impossible to make more than a certain quantity of air pass through the oxidator in a given time, and that the quantity of carbon consumed, is in proportion to the quantity of air supplied, we are forced to the conclusion that a much smaller quantity of camphine or naptha vapour must be used than if we employed a less carbonized substance, as oil ; and such we find in practice to be the case : the, consequence is, that though the flame is bright, it is very small ; in the best camphine lamps never being more than three-quarters of an inch in height without smoking, while in an oil lamp it may reach as great a height as three inches, which, though at no one point so bright as the small flame, mil, ou account of its greater size, throw a really larger amount of light...« less