THE WEATHER MAP

CIRRO-STRATUS

The appearance of this cloud precedes by a day or so the arrival of rainy and stormy weather

This cloud marks the summit of an ascending air current, and appears toward midday or early afternoon in the warm season. When the air rises powerfully to great heights, cumulus is built up in mountainous masses and may become cumulo-nimbus, the thundercloud.

ASCENT OF A SOUNDING BALLOON

The first made in the United States; at St. Louis, Mo., in 1904