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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.

I t 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 supplementary 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], 1 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 considerable part in their early construction. I had also made