LIST OF FIGURES

FIGURE		PAGE
Instrument Shelter [(Figure 4)]		Frontispiece

[1.]	Winter and Summer Vertical Temperature Gradients, in degrees Centigrade and Fahrenheit	12
[2.]	Showing light from lamp a passing into dust-free air at b, and passing out at c without illuminating the interior	46
[3.]	Standard Weather Bureau Kite	64
[5.]	Comparison of the Thermometer Scales	67
[6.]	Dry and Wet Bulb Thermometers	68
[7.]	Mercurial Barometer	78
[8.]	Continuous records of the temperature from 4 P.M. to 9 A.M.	87
[9.]	Continuous records of the temperature 5 feet and 35 feet above ground on a tower in a pear orchard	95
[10.]	Average dates of last killing frost in Spring	96
[11.]	Average dates of first killing frost in Fall	97
[12.]	Trade wind circulation	99
[13.]	Average surface winds and pressure of the globe	102
[14.]	How winds would blow into a cyclone on a non-rotating earth	108
[15.]	Deflection of wind due to earth’s rotation	109
[16.]	Annual, summer, and winter wind velocities with altitude	110
[17.]	Tornado Cloud	145
[18.]	The St. Louis Tornado of May 27, 1896, Shot a Pine Scantling through the Iron Side of the Eads Bridge	147
[19.]	The St. Louis Tornado of May 27, 1896, Shot a Shovel Six Inches into the Body of a Tree	147
[20.]	The St. Louis Tornado Drove Straws One half Inch into Wood	149
[21.]	Equinoxes, March 21 and September 22	163
[22.]	Summer Solstice, June 21	164
[23.]	Winter Solstice, December 21	164
[24.]	Winter and Summer Solstices, and the Equinoxes	165
[25.]	As angle of incidence decreases from 90° to 10° the heat received on upper end of blocks is spread over greater area at bottom, and its temperature diminished	165
[26.]	Altitude attained by Sun at midday and length of its track above the horizon at the Summer and Winter Solstices and at the two Equinoxes	167
[27.]	Summer day and Summer night temperatures in the same narrow valley	204
[28.]	Average Monthly Temperature and Rainfall of Typical Places in North America	207
[29.]	Average Monthly Temperature and Rainfall of Typical Places in the Old World	208
[30.]	Changes in Climate in California during the Christian Era	237
[31.]	Snow Crystals	286