146 Scientific Intelligence. 
positive, negative, or neutral, a number us exhaustive experiments 
have lately been undertaken in the Physical Laboratory at Berlin 
by Mr. Blake under the seam ee: of Helmholtz. It was found 
that the vapor arising from the electrified <n erst was 
neutral.— Annalen der Physik und Chemie, No. 7, 
3. Constant of Dielectricity.—The i aaa i theorpen 
light is attracting so much attention that experiments upon elec- 
ream —- in dielectrics are becoming of great i, a 
Quin measured the constants of dielectricity and t 
carte caine of insulating fluids. Using Maxwell’s peak: 
ee 
my ane 
which p vg, aie the stress along lines of electrical force, 
P denotes the difference of electric potentials, a the distance be- 
placed, K, the dielectricity constant, or the number which rep- 
resents the increase of the capacity of a condenser when the 
onfi 
table of the constant for fifteen liquide: is given. The double re- 
fraction of insulating fluids is also examined and is found to be 
variable. It is given in terms of a coefficient defined by es 
—Phil. Mag., Jul y, 1883, pp. 
. Conservation of Solar Energ gy-—The June number of he 
Philosophical Magazine contains an article by E. H. Cook on 
Siemens’s new theory, in which the author proves that CO, is dis- 
tributed uniformly throughout our atmosphere, and concludes that 
the power of gaseou oe is such as to equalize the dispro- 
portion of gases which Siemens finds necessary for his hypothe- 
sis. Siemens in reply admits as uniform distribution of CO, In 
our atmosphere which is subjected to powerful circulating enr- 
rents, but does not think that gaseous diffusion can work quickly 
enough to interfere with his Bi currents. The — of 
The metallic vapors in dhe Lag ee are chiefly due to me- 
chanical intermixtures. The metallic va thus introduced into 
the photospheric current will te ones and as jected outward into 
space, not as a vapor as supposed by Mr. Coo »_but as a metallic 
portion of which will accor ne to cores return to the sun by _ 
virtue of solar gravitation and be dissociated on reaching the 
gaseous metallic sea iieriing the es here. Siemens then 
aims to show that the light metallic “vapors will be held in sus- 
pension in this metallic ocean in the same way that oxygen and 
regard to Mr 
i oe carbonic fk bee are retained in sea pases In re . 
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