218 HISTORY OF SOUTHEAST MISSOURI I. ing water is compared to the escape of steam from a boiler by some of the observers. Au- dubon speaks of the sound as if it were "the distant rumbling of a violent tornado," while Bradbury mentions the fact that he "was awakened by a tremendous noise" and noticed the fact that the sound which was heard at the time of every shock always preceding it at least a second and uniformly came from the same point and went off in the opposite direc- tion. Other observers describe the sound in dif- ferent ways. One said "'when the shocks came on the stones on the surface. of the earth were agitated by a tremulous motion, like eggs in a frying pan, and made a noise similar to that of the wheels of a wagon in a pebbly road." Others speak of the sound as resem- bling a blaze of fire acted upon by the wind, or the wind rushing through the trees, or a carriage passing along the street, or distant thmider. P Tlie effects of the earthquake on the surface of the earth itself may be summed up as con- sisting of fissures, sand-blows, a rising of parts of the earth and sinking of other portions, faulting of the crust and in some cases land slides. One of the most common of these phenomena was fissuring; the earth waves which we have described as accompanying the shocks burst in many cases, leaving a fissure, some of these as long as five miles. This was an estimate made by LeSieur ; others mention fissures 600 or 700 feet long and 20 to 30 feet wide.* Flint says that some of the fi.ssures were wide enough to swallow horses or cattle, t He also says that people fell into these fissures and were gotten out with great diffi-
- Foster, The Mississippi Valley, p. 19.
t Flint, Eeeollections of the Last Ten Years, p. 226. culty. In some instances the inhabitants felled trees crosswise of the fissures and took refuge on their trunks to prevent being swal- lowed up. Out of these fissures there were ejected quantities of water and sand; mixed with the sand in many cases were particles of coal or lignite. This lignite seems to have been a feature of the sand which was thrown out from the fissures, and much of it is still to be found in many places throughout the district. ]Iost of the contemporary accounts speak of it as "carbonized wood" or lignite. The material seen by Lyell near New IMadrid is described in one place as bituminous coaly shale (clay), such as outcrops in the river bank and is found in shallow wells 35 feet or so below the surface and in another as lignite. The best description of its behavior on combustion is given by Mitchill, who ex- amined samples submitted by a correspondent. I found it very inflammable ; it consumed with a bright and vivid blaze. A copious smoke was emitted from it, whose smell was not at all sulphurous, but bituminous in a high de- gree. Taken out of the fire in its ignited and burning state, it did not immediately become extinct, but continued to burn until it was consi;med. "While blowed upon, instead of being deadened it became brighter by the blast. The ashes formed during the combus- tion were of a whitish color and when put into water imparted to it the quality of turn- ing to a green the blue corolla of a phlox whose juice was subjected to its action Some specimens of the lignite matter were coated with a whitish or yellowish substance, suggesting sulphur, but it was probably the sulphate of iron common in lignite and cer- tain coals. Wood not lignitized was also re- ported by some observers.^ Another form of fissure seems to have been formed only near banks of streams ; the por- t IT. S. Geological Survey, Bulletin 46.
