62 Scientific Intelligence. 
obtained a solid product of condensation from benzol, not volatile 
at the temperature at which glass fuses. He had called it bitu- 
mene; Thenard’s product was undoubtedly of the same kind, per- 
haps more condensed.— C. #., Ixxviii, 219. Moniteur Scientifique, 
III, iv, 265, March, 1874. G. F. B. 
6. Nitro-compounds of the Allyl series,—BRACKEBUSCH has con- 
tinued his researches on the production of nitro-derivatives b 
f : ; 
° 
sodium-nitro-propylene, is produced ; in complete analogy with the 
nitro-derivatives of the fatty series. Potassium acts similarly. 
pump. Th spirit flame 
across the lower part, when the pith-ball descended slightly, and 
then rose to above its original position, as if there was first an 
attraction, instantly overcome by the air-current. The same effect 
was obtained with a glass bulb containing water at 70°, the pith- 
ball rising whether the heated body was a Ben or below it, though 
less rapidly in the latter case. e pump was now set to work, 
when the action became less and less, until with a pressure of 
7 mms. it ceased entirely. It seemed evident that the effect was 
due to air currents, and that in a vacuum no action would ensue. 
bh 
incandescent by an electric current was next enclosed in the 
tube, an ‘ass balls were i 
seemed to be to bring the center of gravity of the brass ball as 
