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and the merchants would use their influence in collecting 
specimens, and the town provide a museum for their reception, 
this Society might appoint committees of scientific men to 
report on the uses for which such products were best suited, 
and the result of their labours might be published. Up to this 
time commerce had not sought the aid of natural history and 
chemistry to the extent which it might have done. For a 
commencement the Natural History Society would probably 
afford the use of a room, in which the specimens could he 
exhibited. 
Mr. Alfred Fryer stated that he had recently been 
making a series of experiments with the oxyhydrogen light, 
with a view to determine what substance made incandescent 
produced the greatest amount of light. He operated on 
various salts of calcium, magnesium, strontium, barium, and 
also upon some other substances. The best results were 
obtained from magnesium. The sulphate of magnesia, when 
baked, yielded a bright light, hut was decomposed by the 
heat ; and the sulphurous acid escaping was very unpleasant. 
Calcined magnesia succeeded the best of all ; hut when the 
powder was used, the gases blew it away. When the powder 
was mixed with water, and afterwards dried, the cake was 
friable ; and when the dry powder was pressed in a mould 
by means of hydraulic pressure, the cake split up into laminse 
when subjected to the gases. After many experiments with 
the materials in different proportions, it was found that 
sulphate of lime one part, and calcined magnesia two parts, 
mixed rvith water and modelled into a cake and dried, 
produced the best results. This, however, is not all that 
could be desired, as in time the cake becomes cracked and 
fissured by the gas. The illuminating power is to that of 
lime, pressure and volume of gas being equal, as 54 is to 27. 
The experiments have been conducted with oxygen and 
the coal gas supplied to Manchester. The jet used is a form 
