148 Scientific Intelligence. 
already been produced. Mrtier has now phase! the sixth, 
which has the carboxyl and the two hydroxy! groups in the posi- 
tions 1:2:3 respectively, and which he ai catechol-orthocar- 
boxylic acid, Two different methods were used: in the first, 
the second, Larpaiaie A foe acid was heated with an excess of 
potassium hydra rms wart-like groups when anhydrous, 
melts an Tosre ines at 204°, gives a deep blue coloration with 
Fe,Cl, which changes to violet-red with Na,CO,, is easily soluble 
in hot water, alcohol and ether, and gives with lead acetate a 
flocculent precipitate.—d/. Chem. oe. xli, 398, Nov., phe 
<h 
Conservation of Solar Hnergy.—SteMens replies to “the 
whee of G. A Hirn, Comptes Re ndus s, Nov. 6, 1882, and 
8 
of the greatest penty light we can produce, and cannot be far, 
therefore, from 2800° C., and that the dissociation urged by Hirn 
would not aio sous ‘In regard to absorption in interstellar 
s : 
piemer Langley, and the opinion of many astronomers, that 
I the mechanical resistance exerted by the gaseous 
matter tN Siemens supposes to exist in space, Siemens cites 
the experiments $7) Mr. illiam Froude (British Association, 
1875) in regard to the movements of solids in fluids From 
cles over each other or over the surface o ies Id_not 
meet with resistance of any kind. He applies this experiment to 
his theory, and strives to meet the objections e Bi 
Comptes Rendus, No. 22, Nov. 27, 1882, pp. 1037--1 
6. Conservation of Solar Energ, y.—M. G. A. Haw goa to 
Siemens, and reiterates his opinion that the minimum apie rig 
of the sun is 20,000° nia and that the Gavociation to which he 
calls attention in his vious pene will oce He also main- 
tains his conclusions in regard to the density "of the fluid ling 
interstellar space. 
a arcs impossible.— Comptes Rendus, 
8. 
7. Reduction of the seated Ss Unit of Electrical resistance to 
absolute measure.—E. N, modification of Weber’s second 
method, used also by Kohiransch, has obtained the following 
value: 1S. E.=0,9482 10" ? D tehaes S. E. denotes the Siemen oF 
