42 KANSAS CITY REVIEW OF SCIENCE. 



they do not; on the contrary they move on very irregular lines, and at times take 

 a direction of 45° and even 90° to the parallel of latitude. Sometimes taking a 

 northeast or a southeast course, zigzag, like the letter W ; and they even at times 

 travel due west. But whatever their local direction ; their general course is the 

 while from the west toward the east, or towards the rising Sun. The changes 

 are infinite : " Low" being the governing factor, it is necessarily the one about 

 which the most may be said. It may be asked, — What is " Low " ? 



There is no branch of science but what leads up to some unknown power or 

 cause. In meteorology " Low " is the great unknown. We know that it exists. 

 We know how it passes over the country, and know its effects. But why should 

 it obey the law it does ? At this point I shall submit a theory, the only theory 

 about the whole subject. I do not claim for it more than its name implies, "a 

 theory," and I have no desire to hold to it if unsupported by reason and fact, 

 and am ready at any time to accept a better reason or explanation whenever 

 offered. 



"Low" is the concentration of the Sun's rays, and may well be illustrated 

 by the double convex lens, commonly called a "Sun-glass," when passed over a 

 paper and so held as to focus the rays of the Sun. We will the better under- 

 stand the theory by imagining ourselves to be present when the well formed 

 earth is started in space. 



The surface of the earth is varied. This feature necessarily causes uneven- 

 ness of latent forces when the heat of the Sun is caused to concentrate on 

 some one favored point. The heat acting on the water is the while forming 

 clouds. The concentration of heat causes rarification of the air at this point — 

 Nature's attempt to form a vacuum. The cooler surrounding air rushes in to fill 

 the place of the rarified air ; a current of air, called wind, towards this point, is 

 the result. This brings the clouds that have formed, from all points of the com- 

 pass, towards this center. These clouds not only precipitate and thereby help 

 cool the surrounding air, but they shut off the heat from the Sun. The heat 

 from the Sun then concentrates on another point a thousand or two thousand 

 miles distant, and the same result follows — around the world. The next day 

 when the Sun reappears in the east the first " Low" is drawn towards the new, 

 or last one, which relatively lies to the east — call it No. 12. No. 2 is drawn 

 towards No. i; No. 3 to No. 2, etc. Thus the "Lows" travel till they form 

 well established belts around the world. Between the "Lows" are located the 

 "Highs." 



If "Low'' is the concentration of heat and thus moves along the earth's 

 surface, the question may be asked, why does it not, after mid-day, travel to- 

 wards the west ? It does at times, and is at all times undoubtedly retarded in its. 

 course towards the east. Whether this theory is true or not we cannot deny the 

 fact that " Low " travels as it does, on general lines, from the west towards the 

 east or towards the rising Sun. 



The surface movement of the wind is towards this center. But as the winds 

 coming from the four points of the compass react upon each other, their direc- 



