INTRODUCTION

How tornadoes, hurricanes, and cyclones work was once one of the great scientific mysteries, especially in the nineteenth century. The word “tornado,” however, was created sometime in the late sixteenth century. It was a combination of two words tronada, which means thunderstorm, and tornar, which means to turn, twist, return. British sailors seem to have used it first. There was a mysterious quality to these storms, and people were intrigued. In the first half of the nineteenth century, there was a great “Storm War” over the nature and causes of tornadoes. On one side of the conflict was James Espy and on the other side was William Redfield.

Building on the ideas of John Dalton, Espy in the early 1800s developed the idea of what is now known as convention, in which heat creates columns of rising air that pump warmth and humidity into the cold air aloft. Clouds then form and rain falls. He believed that the mechanism that fueled tornadoes was a rapidly rising column of hot air within the mysterious black funnel of the tornado. He did not believe that the funnel cloud was rotating. Rather, he believed that the winds were drawn into the central column from all sides in perfectly straight lines, like the spokes of a wagon wheel and from there they rose up in perfectly straight lines through the clouds to the sky. The updraft was created by the differences in temperature and pressure between the surface and the upper air. At the end of the 1830s, Espy was awarded the title “Storm King” by the reporters covering his appearances.

In 1821 William Redfield followed the aftermath of a severe storm and noticed that some of the trees were knocked down by a wind from the east while other trees were knocked down by winds from the west. While on the surface it looked as if two identical storms had passed each other in opposite directions, he proposed that the storm had been a gigantic whirlwind, spinning around a moving center like a top.