150 KANSAS CITY REVIEW OF SCIENCE. 



present investigations of this most terrible and yet most wonderful and interest- 

 ing of storms, the dreaded tornado. 



THE TORNADO. 



What is a tornado ? In defining this storm it would seem almost a necessity 

 to rehearse its long line of striking characteristics, but this in the common ac- 

 ceptation of the term would not strictly be a definition. At the sacrifice perhaps 

 of clearness, but for the sake of brevity, we will state that the tornado is that 

 form of atmospheric disturbance which takes the outward, visible fashion or fig- 

 ure of a funnel-shaped cloud, revolving about a vertical axis from right to left 

 with an inconceivably rapid movement and an immensity of power almost be- 

 yond calculation. 



Conditions of Formation. — These may be divided into classes. First, 

 those within the reach of and which may be known or investigated by an isolated 

 observer. Second, those conditions only to be witnessed and analyzed by the 

 intelligent and practiced eye of the student of the Weather Map. To the single 

 observer, located mayhap at his farm home, the work-shop or the store, there 

 are important atmospheric conditions which he may carefully watch and study 

 with profit, viz : the gradual setting in and prolonged movement of the air from 

 the north and south points ; the gradual but continued fall of the thermometer 

 with a prevalence of the former currents, and a rise with the predominence of the 

 latter. If the northerly currents are the prevailing air movements at your place of 

 observation, the atmospheric disturbance is forming to the southward, but 

 to the northward of your location, if the prevailing air currents are from the 

 south. Carefully study cloud development, color as well as form, also manner 

 and direction of approach. The approach of the cirrus cloud (perhaps at a height 

 of six to eight miles) from the southwest is very significant and is the first evi- 

 dence of the gradual, but certain advance of the upper southwest current which 

 eventually plays so important a part in the development of the tornado cloud. 

 Clouds are but the embodiment of air currents, yet they are full of meaning. A 

 study of the upper currents of the atmosphere would be impossible without their 

 manifestations and that too in a variety of forms. Dispense with cloud formation, 

 the face of the sky would become a blank, and intelligent reas ning thereof a 

 superhuman task 



Wind direction, temperature and clouds are the proper subjects of observa- 

 tion and thought by the isolated observer. The barometer is of little if any im- 

 portance in this line of inquiry. If you cannot compare your barometric obser- 

 vations with those taken at near or distant points and at the same moment of actual 

 time, they are of no practical moment, even though your instrument is a standard 

 one and your corrections for temperature and elevation carefully applied. The 

 storm you are watching for (the tornado) is an extremely local affair, whereas the 

 barometer indicates general changes, affecting a large extent of country. Your 

 instrument, if a standard, does not lack the possession of a delicate sensitive- 

 ness requisite for all the purposes of its construction. But if it were placed in 



