It is this rapid onslaught from Montana to Texas that produces those notorious blizzards of that section called northers, during which the cattle used to be frozen on the hoof. The record time for a drive of this extent is about twelve hours and the normal about twenty-four which gives scant time for the Weather Bureau to warn the vast interests of the impending assault. When the cold wave, after following this path, does swing toward the Atlantic Coast, as most of them do, it has lost interest and usually produces only seasonably cold weather along the Appalachians. Those cold waves that recruit their strength in Canada and enter the United States through Minnesota or, rarely, this side of the Lakes move along the border and supply intensely cold weather for a night or two to New England and the Middle Atlantic States. Cold waves almost always follow a storm. The storm, being an area of low pressure makes a fit receptacle for the surplus of the high pressure, and since the whole business of the weather is to seek peace and pursue it, the greater the discrepancies the more violent the pursuit. Consequently we have the spectacle of a ridge of cold dry air following and trying to level up a fleeing hollow of warm moist air--but rarely succeeding. This principle of action and reaction is almost the sole principle of the weather and is nowhere more clearly demonstrated than in the winter's succession of storm and cold wave. In summer the anticyclones are not only actually but relatively more moderate than in winter. But their influence is still the same,--clear skies, cooler nights, dry, westerly winds. During the year the anticyclone furnishes us with about sixty per cent. of our weather. The cyclone is responsible for the remaining forty per cent. The weather depends on the cyclone for its variety and upon the anticyclone for its reputation. So it is well to be able to recognize an anticyclone when one appears. The first and most reliable symptom of the approach of an anticyclone is the west wind. This sign is valid the country over, and is one of the very few signs that hold true for most of the North Temperate Zone. In summer over our country the west wind comes from the southwest, to be Irish, and in winter from the northwest. But for nearly all of our forty-eight states for nearly all of the year the westerly winds are those that bring us fair days and nights. And it is these crisp, clear days and cloudless, brilliant nights which we have in mind when we boast to English friends of our American weather.