KEW OBSERVATORY AND METEOROLOGY 231 



stations much closer together than those in the maps 

 of Le Verrier, and yet would embrace a sufficiently 

 large area to exhibit the details of a complete weather 

 system. I took a great deal of pains about this, and 

 finally succeeded in 1862 in obtaining what was 

 wanted. 



It was with no small eagerness that I set to work 

 to map out the data. The month began under 

 cyclonic conditions ; then, to my intense delight, as 

 that system passed by, it was followed by a condition 

 of affairs the exact opposite to the cyclone, and supple- 

 mentary to it. The cyclone, as already said, is an 

 uprush of air, associated with a low barometer and 

 clouds, due to the hot and moist air becoming chilled 

 as it rose, and it was fed, as just described, by an 

 indraught with an anti-clock-ways twist in the northern 

 hemisphere. That which I now found, during the 

 latter part of the month in question, was a downrush 

 of air associated with a high barometer and a clear 

 sky, and with an outflow having a clock-ways twist. 

 The one system was clearly supplementary to the 

 other. So in the memoir I contributed on the subject 

 to the Royal Society [16], I called the newly 

 discovered system an "Anti-cyclone." Speaking 

 broadly, the whole of the movements of the lower 

 strata of the air are now looked upon as a combination 

 of cyclones and anti-cyclones, which feed one another. 

 The name established itself at once, and is now 

 familiar. 



The present daily weather charts of the Times, 

 from data supplied by the Meteorological Office, began 

 to appear at a subsequent date, and I took consider- 

 able part in their early construction. I had also made 



