Owatonna, MN Tornado, Jul 1870

A Western Tornado.

A SINGULAR ELECTRICAL PHENOMENON AND A NOVEL THEORY.

A tornado passed over some parts of Minnesota, a few days ago, which was marked by the same characteristics as that which visited some parts of this State and New England about the same time. It was very severe in some towns, while in the neighboring places it was not felt at all, or at most was scarcely noticed, and it appeared to travel in a narrow path. A writer in the St. Paul Press, who witnessed the storm at Owatonna, in the southern part of Minnesota, gives the following account of its singular appearance there:

"This morning at about half-past two o'clock this city was visited by the most terrific and destructive tornado which it has ever known. The Round House of the Winona and St. Peter Railroad Company was unroofed, and a large portion of the walls demolished. The engine 'Clermont' was nearly buried in the debris, but sustained no serious damage. The night watchman was in the house when it fell, but found safe refuge in the pit underneath the engine tender. The wheel of the windmill of the eminence west of the city was completely destroyed. This wheel was nearly one hundred feet in diameter. A large ice-house was blown to atoms. The cheese factory was so badly damaged as to be unfit for further use without repairs, and I am told that the summer's accumulation of cheese must be removed."

"The upper portions of the fronts of several buildings was blown off; awnings and sign boards were badly damaged; trees and garden fences suffered severely, and chimneys and outbuildings were generally capsized. Some roofs were badly broken, and others damaged but little.."

"There was neither rain nor hail. There seemed to be one current approaching the city from the southwest and another from the southeast, and when I first noticed these currents they were quite distant from each other, but they rapidly approached, converging directly upon the city. When apparently a mile away, there appeared midway between the two currents, and at a low elevation, a light, small at first, but gradually increasing until it reached the size of an ordinary hogshead. Its base was parallel to the surface of the earth. The sides seemed to approach each other at an inclination of about thirty degrees. At the top of this cone, and apparently just separated from it, appeared a bright blaze, which shot toward the zenith in forked flames, I judge from ten to fifteen feet in height. The cone beneath the blaze seemed to revolve rapidly around an axis, vertical to the centre of the earth. The brilliancy of this air-fiend became constantly more intense as the currents approached each other, and its revolutions became proportionately more rapid, until in the shock caused by the collision which occurred on Cedar street, some fifty rods north of the public square - a terrific and deafening sound was heard, followed by a dispersion of some fifty fragments of electrical light, in apparently solid form. These were seen richocheting[sic] in every direction, approaching the earth, and withdrawing from it in fantastic, though appalling gyrations. The scene of this phenomenon was the region of the greatest disaster. The wind blew sharply, but did not do the damage. There was a fierce and terrible force in the air, not the air itself, which nothing could withstand. Single shingles were plucked from roofs. One picket was torn from the fence while its fellows were unmoved. A single row of onions in a neighbor's garden were torn from the ground, and the others left to grow and ripen undisturbed."

"The foregoing facts furnish data upon which I base the following: The excessive heat of the two preceding days was such as to produce great disturbance in the atmosphere, and to give rise to the formation os strong aerial currents, which, after becoming complicated, rioted awhile in close combat, and then separated, perhaps by electrical force, forming again in different quarters - two strong channels of moving air emerging upon a common centre. Approaching each other, the space through which the electricity inherent in the air was diffused became rapidly less, and still less, at the same time it would be carried along by its own adhesion to the moving mass of clouds. It thus became gradually condensed, and by its own motion, together with the constantly increasing pressure of the approaching currents, forming walls through which it could not break, and the friction caused by the mobility of its own particles upon themselves, intensified the heat until it became first luminous, then lambent, then concentrated in tangible form, and finally yielding to the power of its own explosive force, burst asunder, forming numerous balls of concentrated fire, which discolored and spend their fury on surrounding objects."

"Traces of this tornado are visible as far east as Lewiston, unattended, however, by any serious damage."

The Titusville Morning Herald Pennsylvania 1870-07-29

[Transcriber's Note: For 1870 - or any time - this writer has one of the most amazing descriptions of tornado activity I have ever read .]