302 Dr. John T. Plummer on the 



nouncement of their discovery, and I do not know that much 

 need be added to that information. 



The tusk was exhumed in gravel, fifteen feet below the sur- 

 face, while excavating the Whitewater canal, near Brookville, 

 about thirty miles south of Richmond. It has a chalky white- 

 ness, is very brittle, solid throughout its entire length, which, 

 when the specimen was disinterred, was nearly six feet ; and 

 exhibits at the ends about a dozen concentric laminae of variable 

 thickness. The characteristic zigzag lines are finely displayed 

 at the fractured extremities. The diameter of the tusk is four 

 inches, and the curvature of it is nearly the segment of a circle, 

 whose radius is two and a half feet. 



The grinder was found near Jacksonsburgh, twenty miles west 

 of Richmond ; and though several considerable pieces of it are 

 lost, it weighs four pounds. The interior is spotted here and 

 there with a clear cerulean stain. This mastodon tooth is so 

 well preserved, that before it came into my possession a dentist 

 attempted to make artificial human teeth of the whitest portions 

 of it. It has four pairs of prominences.* 



A club-shaped instrument, formed apparently of cliff limestone, 

 was also taken out of the gravel ten feet below the surface, near 

 the spot where the tusk was found. It is nearly seventeen inches 

 long, rounded at one end and tapering towards the other extrem- 

 ity. It would make a massive weapon, and indeed it has been 

 colloquially called a war-club. It may have been an Indian hom- 

 mony pestle ; and if so, its interment to the depth of ten feet is 

 somewhat mysterious, and constitutes the most interesting fea- 

 ture of the discovery. 



Ancient Wood and Stumps of Trees. — I have long contem- 

 plated with interest that bluish, calcareous clay, noticed at the 

 beginning of this section, (diluvium,) as constituting one of 

 the lower members of our diluvium. By personal inspection I 

 have ascertained that it extends over a large portion of the west- 

 ern country ; I have met with it repeatedly in Ohio, in Indiana, 

 and in Illinois, recognizing it by its physical composition, its color 

 and smell. The interest attached to it arises from its being ev- 

 ery where the repository of relics of vegetation. At Springboro', 



* I will mention here, merely to designate another locality, that another fossil 

 grinder in my cabinet is said to have been found in Trumbull County, Ohio. It 

 has ten prominences. 



