518 Meeting of the British Association. | Oct., 
will cost 12,120/., whilst the estimates for the Berlin laboratory, 
with its 74 rooms, amount to no less than 47,7151. 
Dr. Phipson sent a note “ On Sulphocyanide of Ammonium,” a 
substance which he says exists in somewhat large quantities in com- 
mercial sulphate of ammonia, sometimes to the extent of 75 per 
cent. One of the most remarkable properties of.this salt is its pro- 
perty of producing intense cold when dissolved in water; 500 
grammes mixed with a litre of boiling water, reduced the tempera- 
ture to near the freezing point in a few seconds. 
Professor Abel, F.R.S., sent “An Account of the Great Cannon 
of Mohammed II., recently presented by the Sultan Aziz Khan to 
the British Government.” The date of its casting is 1464. It has 
been applied to defensive purposes for four centuries. The compo- 
sition was found to vary between copper 89°58, tin 10°15 per cent., 
and copper 95:20, tin 4°71 per cent. 
Mr. Spiller gave “An Analysis of the Ancient Roman Mortar of 
the Castrum of Burgh, Suffolk.” He finds, contrary to the generally 
received opinion, that the hydrate of lime becomes entirely recar- 
bonated in course of time, and that the silica and lime have not 
united with each other in the long interval of fifteen centuries. 
Dr. Matthiessen and 8. P. Szezepanowski sent in “A: Report 
on the Chemical Nature of Cast-iron.” Although they have made 
seventy series of experiments, they have not been able to prepare 
iron free from sulphur. They are still prosecuting their search for 
a method of preparing pure iron. 
Dr. Frankland, F.R.8., read a paper “On the Combustion of 
Gases under Pressure.” The author finds that the increase of illu- 
minating power is exactly in proportion to the increase of pressure. 
One of the most interesting experiments shown was that of sending 
an electric spark first through air under ordinary pressure, and then 
through air under doubled pressure. The result was, that the light 
of the spark due to ignition of the air was very much increased. 
The spark was sent also through many other gaseous and vapourized 
substances, showing most conclusively that the greater the density 
of the bodies the greater was the luminosity of their flames when 
submitted to ignition by the electric spark. 
Dr. BR. Angus Smith, F.R.S., made a verbal statement of the 
result of some experiments he had been conducting “On the Absorp- 
tion of Gases by Charcoal.” He finds that the gases are absorbed 
in whole volumes, or in volumes which are multiples of hydrogen. 
The following are some of the most curious and important results :— 
hydrogen 1, oxygen 7:99, carbonic acid 22°05. 
