Proceedings. 169 



tion, is due to another of our honorary members, Buchan of 

 Edinburgh, though Buys Ballot was the first to develop the 

 idea of a graphical representation of the distribution of 

 weather. He drew straight lines in a horizontal direction 

 to indicate that the temperature was below the average, 

 vertical lines were drawn wherever the temperature was 

 above the average, and the shading was so arranged that the 

 greatest deviation from the average was indicated by a 

 stronger line. The region comprised in these charts 

 extended over central Europe." 



Examples of Ballot's charts were exhibited, and a dis- 

 cussion on general meteorological questions ensued, special 

 reference being made to the hypothetical relations between 

 atmospheric pressure and coal-mine explosions. Mr. 

 FARADAY mentioned a new theory, started in a London 

 paper, to the effect that explosions are rather coincident 

 with a high than a low barometer, and that the increased 

 atmospheric pressure on the earth forces out the gas. The 

 PRESIDENT held that it is probable that the tendency to 

 explosions in autumn and winter is due to the rising of the 

 underground water rather than to any changes in the 

 barometer, and also that probably there is more work going 

 on then than at other periods of the year. Mr. Brogden 

 maintained that the conditions of collieries are so dissimilar 

 that different circumstances have different effects in different 

 collieries, but he thought that all changes of pressure mark 

 the times of danger. The issue of blowers of gas is 

 probably little affected by changes of pressure. 



General Meeting, March 4th, 1890. 



EDWARD Schunck, Ph.D., F.R.S., F.C.S., Vice-President, 

 in the Chair. 



Mr. H. A. HENDERSON, of Manchester, was elected an 

 ordinary member. 



