106 PROCEEDINGS OF THE INDIANA ACADEMY OF SCIENCE. 



ing, the odor arising from it can be perceived about half a mile from the Lick, 

 and the ground over which it flows is black, owing to the iron Avhich it con- 

 tains being converted into a sulphuret of this metal. 



"Those who reside in the immediate neighborhood of this spring and under 

 the influence of this gas during the months of July and August are frequently 

 attacked with fever and ague; while those living on the higher ground, and 

 out of the influence of the immediate atmosphere of the sulphuretted hydro- 

 gen, remain quite healthy. This fact, which can be attested by all the in- 

 habitants of this region, seems to prove that the existence of sulphuretted 

 hydrogen in the atmosphere is one of the predisposing causes of intermittent 

 fever." 



Dr. Owen makes no reference to the mosquitoes of the region which, in 

 those days, doubtless bred by mj'riads in the pools along the streams below 

 the outlet of the springs, the runoff water being comparatively fresh after 

 its gases had escaped into the air. 



Continuing, Dr. Owen describes briefly the whetstone rock formation 

 near French Lick and under "Harrison County" mentions and explains 

 the cause of the numerous sinkholes and caves of his so-called Barren Lime- 

 stone (Mitchell) of the region. Under "Floyd Countj " he gives a detailed 

 geologic section of the formation from the bed of Silver Creek to the top of 

 the Knobs, and also one derived from borings through the black slate and 

 underlying strata. Continuing farther eastward he gives a section of the 

 noted railway cut near Madison, and states that he met Dr. Locke, one of 

 first Geologists of Ohio, with whom he traced tlie extent of the Magnesian 

 limestone along the common bomidary of tlie two states, from the Ohio River 

 to Union County, Indiana. From hen* Dr. Owen passed on northwest to 

 Wayne County, and from there to Muncietown and Andersontown, as they 

 were then knowTi. He describes the "white gritstones" outcropping at the 

 falls near Pendleton and states that they might perhaps be fit for making 

 glass, a use to which they were afterwards extensively put. Proceeding north- 

 ward, he mentions the first appearance of a limestone formation on the head 

 waters of the Wabash, ten or twelve miles west of the Ohio line, and states 

 that "the Wal)ash then flows almost uniformly over ledges of rocks for about 

 100 miles to Delphi in Carroll County." 



He considered it remarkable that a nearly- flat prairie country should, in 

 northern Indiana, form the dividing ridge between the waters flowing into 

 the Great Lakes and those running into the Gulf of Mexico, and that the 

 larger streams of that section, "instead of commencing by confined mountain 

 torrents, should rise from widely expanded sluggish springs in Tamarack 

 swamps, and flf)w for 80 or 40 miles with little perceptible fall." He states 

 that there are many reasons for believing that the St. Joseph and the St. 

 Alarys, which unite near Fort Wayne and then turn and flow northeastward 

 into Ohio, once flowed down the Wabash. (Continuing southwestward, he 

 mentions the rock, then as now, being worked in the extensive quarries at 

 Kenneth, three miles below Logansport, and states that "The whole of the 



