420 Scientific Intelligence. 
e 
their very beautiful and valuable investigations—Pogg. Ann., cx, 161, 
June, 1860. 
[Norz.—The inferences of Kirchhoff and Bunsen with respect to the 
chemical nature of the sun’s atmosphere require two assumptions neither 
of the sun is intensely luminous and that its spectrum contains noglark 
f which our earth 
2. On some numerical relations between the densities and equivalents of 
certain elements —PLAYFAIR has communicated to the al Society of 
Edinburgh some remarkable observations on the densities of several of 
the elements. The numerical relation which the author has detected 
amounts simply to this—that the densities are in certain cases accurately 
represented by the square roots, cube roots, or fourth roots of the equiva- 
lents. In obtaining the densities, the author takes a mean of all the best 
recorded observations in each case. The following table exhibits his re- 
sults which are certainly very striking, the coincidences being too numer- 
ous and too perfect to be accidental : 
Equivalents. Density as found. Density as Cajculated. 
Diamond, 12 3°48 4/12 = 346 
Graphite, 12 2°29 37, 12 = 2:28 
Charcoal, 12 1:38 4,12 = 1°36 
Silicon, (adamantoid,) 14-2 2°46 2/ 14:2= 2:42 — 
Silicon, (graphatoid,) 28-4 2°33 4/ 28:4 2°30 
Boron, (adamantoid,) 7-2 2°68 af 7:2 = 2°68 
romine, 80:0 2:98 4/ 80 = 2°99 
Iodine, 127-0 4:99 3/ 127 = 5:02 
Sulphur, 16 2-00 / 16 = 2°00 
Selenium, 80 4°31 47 80 = 4:31 
a note itional experr- 
ments ; by Franx H. Srorer.* Under date of Feb. 24, 1860, Mr. King 
writes to the Editor of the London Journal of Gas Lighting, etc., (see 
vol. ix, p. 111,) as follows: “ Sir,—Having recently tried some experi- 
tained might prove not uninteresting to some of your readers, more espe- 
cially as it is a subject of practical importance, and does not seem to have 
attracted the notice which it ; 
The following table exhibits the amount of light lost by the use of the 
various shades therein enumerated :— 
* Communicated for this Journal, by Mr. Storer. 
