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and the merchants woukl 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 

 aiford the use of a room, in which the specimens could be 

 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, but was decomposed by the 

 heat ; and the sulphurous acid escaping was very unpleasant. 

 Calcined magnesia succeeded the best of all ; but 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 with 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 



