68 Scientific Intelligence. 
2. On the Decomposition of Glass by Capillary water-layers 
containing Carbonic acid.-—Two years ago, Bunsen published 
the results of some experiments which he had made on the con- 
densation of carbon dioxide gas upon the surface of glass (Ann. 
Phys. Chem., xx, 545). His results showed that in three years 
57135 c. c. of ‘this gas were condensed upon each square meter, 
Kayser subsequently repeated the experiment in a different form 
and obtained different results ; whereupon Bunsen reéxamined 
the subject and showed that his glass fibers were not perfectly 
dry, and that a part of the obser ved absor ption was due to this 
capillary water-layer. On taking the apparatus down, Bunsen 
analyzed the glass fibers on which the action had taken place. 
Under ordinary conditions carbon dioxide does not attack glass, 
but it is quite possible that so concentrated a solution of carbonic 
acid as existed in these’ capillary layers, might have some action. 
The analysis showed not only that the glass had been acted on, 
but that this action had been unexpectedly great. A weight of 
49°543 grams of glass fiber gave to cold water sufficient sodium 
carbonate to yield on the addition of hydrochloric acid and evap- 
oration, 0°8645 gram sodium chloride. From the composition of 
this glass, determined before the experiment, it appears that during 
the course of the observations—109 days—5:83 per cent of the 
entire weight of the glass must have been thus decomposed. The 
suggestion is an obvious one that possibly all the absorption, 
which Bunsen observed, might have been due to the formation in 
this way of sodium carbonate. But he shows that of the total 
volume of gas absorbed by the entire mass of glass, 236°9 cubic 
millimeters are set free again on heating. If combined as hydro- 
sodium carbonate, the quantity of sodium found on analysis would 
require only 165°2 cubic millimeters, leaving 71-7 cubic milli- 
meters to be otherwise disposed of. In view of the fact that pure 
water may also be expected to act on the substance of the glass, 
it is evident that glass is not a suitable material for experiments 
on capillary absorption.— Ann. Phys. Chem., Il, xxix, 161; Ber. 
Berl. Chem. Ges., xix, 729, (Ref.) November, 1886. G. F. B. 
3. On the Pr operties and Constants of Germanium.—WINK- 
LER has communicated some additional facts concerning his new 
metal, germanium. When obtained, either by reducing the oxide 
in acurrent of hydrogen or by gently igniting a mixture of the 
oxide and starch, and then fusing the gray powder under borax, 
the metal appears of a grayish-white color, having a brilliant 
metallic luster and crystallizing in well formed regular octahe- 
drons. It melts at a somewhat lower temperature than silver, 
900°, and volatilizes at a slightly higher one than this. It ex- 
pands on solidifying, and crystallizes. Its specific gravity is 
5469 at 204°. Before the blowpipe it fuses to a globule which 
evolves white fumes and explodes, as does antimony. It is in- 
soluble in hydrochloric acid, soluble in aqua regia, and is con- 
verted by nitric acid into the white oxide with evolution of nitro- 
gen dioxide. Concentrated sulphuric acid converts it into a 
