North winds are the cold bearing ones. Clear skies prevail under their influence. Northeast winds are cold, raw snow-bearing winds in winter and spring and bring chilly rains in midsummer. East winds are the surest rainbringers of all for the eastern two-thirds of the country, and are soon followed by rain with a shift of wind over the other third. Their temperatures are more moderate than those of the northeast storms. The greatest falls of rain occur, however, with the southeast winds, whose moisture content is greater than that of the others because they are warmer and blow off water except in Rocky Mountain districts. South winds are warm and contain much moisture, which falls in showers rather than in continuous rains. The southwest winds of winter precede a thaw and are much damper than west winds. In summer over much of our country they are hot, parching winds that injure vegetation. The average velocity of the wind from these different quarters is variable in different parts of the country, the severest being on the southeast and northwest quadrants. The highest winds are always where the steepest gradients are; that is, where the barometric pressure decreases or increases the fastest. The steepest gradients are usually on the northeast and northwest sides of the storm center, with the exception of the Atlantic Coast where the southeast winds are often highest. The average for the northeast quadrant is 16 miles, for S. E. 30, for S. W. 20, and for the N. W. 30 miles an hour. But averages can deceive. As a matter of fact single instances of great wind velocities occur from each point of the compass. The greatest velocity ever recorded at Philadelphia occurred in October, 1878, when the wind blew seventy-five miles an hour from the southeast. But the record velocities for eight of the other months were registered in the northwest quadrant. [Illustration: ALTO-STRATUS _Courtesy of Richard F. Warren_ Not so high as cirro-stratus, and yet partaking of the same skeiny texture. This would be a normal sky in winter about six hours after the veil of cirrus had begun to throw its haze about the sun. No other cloud formations appear, however, and so the area of precipitation is still pretty far away. In summer such a sky is less common. If the disturbance is to amount to anything the cirro-cumulus will soon form. If the wind is from a westerly quarter the blanket of cloud is doubtless a drift from some distant storm, which will not affect this locality. The wind is always blowing toward a storm and away from clear weather.] The period of time when the barometer is beginning to rise after having been very low is that when the strongest winds blow.