WILLIAMSON AND FBANKLIN COUNTIES. 113 



young timber, "which was previously kept down by the annual fires 

 that swept over the county previous to its settlement by the dominant 

 race. 



The principal varieties of timber noticed on the ridges were black, 

 white and black-jack oak and hickory, and on the more level portions 

 of the uplands in additions to these we fiud elm, linden, black and white 

 walnut, sugar maple, black gum, wild cherry, honey locust, bur and 

 post oak, pa-paw, persimmon, sassafras and poplar, and on the creek 

 bottoms the prevailing varieties are cottonwood, sycamore, red birch, 

 coffeenut, pecan, ash, soft maple, redbud, dogwood, elm and hackberry. 



The geological formations to be found in this county belong to the 

 Quaternary and lower Goal Measures. The Quaternary is represented 

 by a series of brown and yellow clays, sometimes mixed with gravel 

 and small bowlders, and ranging from twenty to forty feet or more in 

 thickness. These beds are generally pretty uniform both iu their depth 

 and general character, and seem to partake largely of the character of 

 the saudstones and sandy shales that form the underlaying bed rock. 

 Locally they become quite gravelly, and contain small bowlders of 

 granite, hornblende, quartzite and trap rock, seldom exceeding six 

 inches to a foot in diameter, though a few were seen in the county of 

 more than twice the size just indicated. Nothing resembling the bluish- 

 gray hard pan that constitutes the lower portion of the drift deposits in 

 the more northerly counties was seen here, but the yellowish sandy and 

 gravelly clays that form the main portion of the deposit 'here rest 

 directly upon the stratified rocks of the Coal Measures. 



Coal Measures. 



All the lower coals are found iu this county, the outcrops embracing 

 a part of the conglomerate sandstone that underlays the hilly region 

 along the southern line of the county, and all the succeeding beds up 

 to the horizon of coal No. 10 of the general section. At Bainbridge, 

 three miles south-west of Bolton, in the north-east corner of Johnson 

 county, a seam of coal has been opened about three feet to three and a 

 half iu thickness, which is probably coal No. 1 of the general section, 

 and from the trend of the strata, which is to the north of west, this coal 

 must be found in the south-west portion of Williamson county. Iu the 

 bluff north of Bolton there are two seams that probably represent coals 

 2 and 3 of the general section. The lower one has baen opened at two 

 or three points in the vicinity of the village by tunneling into the hill 

 on the outcrop of the coal, which averages about three feet iu thickness, 

 with a roof of bituminous shale. The coal has a parting of clay shale 

 about a foot above the bottom of the seam from three to four inches in 



—10 



