10 
soda ; the filtrate from this made acid, and a solution of 
ferric oxide again added, this time with the production of a 
blue precipitate indicative of a ferrocyanide. This must 
have existed as ferrocyanide of iron, which on boiling 
with the alkali became oxide of iron and ferrocyanide of 
sodium. There appears to me something curious in the fact 
of these bodies being carried such a distance (in this case 
fully a mile from the gas works) by the gaseous current. I 
should think the ferrocyanogen is the result of a reaction 
between the sulphocyanogen and the metallic or oxide of 
iron. The amount of these bodies must, I think, be far 
too small to have any bad effect on the health of gas con- 
sumers. 
“Jupiter as observed at Ardwick on the night of August 
21st, 1867,” by J. B. Dancer, F.R.A.S. 
The somewhat rare phenomenon of Jupiter without a 
visible satellite extraneous to his disc (as the Rev. W. R. 
Dawes has cori^ctly designated it) has been described in 
the Astronomical Register. I am not aware, however, that 
any notice of it has appeared before this Society, and as few 
observers appear to have enjoyed such favourable atmo- 
spherical conditions as we did in this locality, I am induced 
to offer a few remarks on the appearance which Jupiter 
presented on the night of August the 21st. 
During the early part of the evening the S. and S.E. 
portions of the heavens were covered with thick haze ; be- 
tween 8 and 9 o’clock this gradually disappeared, and the 
atmosphere became clear and unusually favourable for astro- 
nomical observations. Preparations had been made for 
noting the times of the phenomena, but from various circum- 
stances this was abandoned. The observations were made 
with an achromatic telescope of 7J feet focus and 6J inches 
clear aperture. Powers employed, 90, 175, and 300. At 
9 o’clock Jupiter was clearly defined and presented a 
