CENTURY OF IOWA GEOLOGY 409 



Samuel Morton's similar efforts on the Tertiaries of our Atlantic 

 coast, commonly regarded as the initial attempts in America along 

 these lines. ^ By two decades they were in advance of the first work 

 of that pioneer paleontologist, Lardner Vanuxum.* They antici- 

 pate by a full generation the famous investigations of Thomas Con- 

 rad and James Hall, of New York. Nuttall was an English printer 

 who came to this country in 1808, and who during the following 

 year made a western trip in quest of scientific information, reaching 

 the Mississippi river at Prairie du Chien and descending the great 

 stream in canoe to St. Louis. ° 



FIRST RECOGNITION OP CARBONIC ROCKS IN AMERICA 



Another conspicuous feature of rather peculiar significance con- 

 nected with this earliest geological investigation within the boun- 

 daries of our state, is the determination of the presence of rocks 

 of Carbonic age for the first time in this country. In the course of 

 his explanations of the geological characteristics along the banks of 

 the Mississippi river, Nuttall rather naively observes that he is 

 "Fully satisfied that almost every fossil shell figured and described 

 in the Petrifacta Derbiensia of Martin was to be found throughout 

 the great calcareous platform of Secondary [Paleozoic] rocks ex- 

 posed in the eastern part of the Mississippi valley."® Thus by means 

 of the contained organic remains he parallels these Mississippi lime- 

 stones with the Mountain limestones of the Pennine range of Eng- 

 land, to which several years later Conybeare gave the title by which 

 we now everywhere know them. 



At this late day we can hardly appreciate the scant state of knowl- 

 edge concerning the geological column a hundred years ago. When 

 Nuttall arrived on the scene Iowa-land was a perfect terra incog- 

 nita. No scientist had yet laid eyes on the field. Along the Mis- 

 sissippi river, as we now know, the Englishman collected fossils 

 from rocks which are mainly if not entirely Early Carbonic in age. 

 So his identifications of forms were with a few possible exceptions 

 doubtless correct. Moreover, it must be remembered that at that 

 time and for many years afterwards the inferior rocks of not only 

 this country but throughout Europe were entirely undifferentiated. 

 The great succession of older stratified formations which were 

 subsequently successively separated from one another were jumbled 

 together under the title of Transition Group. It was not until a 



'Jour. Acad. Nat. Sci. Philadelphia, Vol. VI, pp. 72-100. 1829. 

 ♦Jour. Acad. Sci. Philadelphia, Vol. VI, pp. 59-71, 1828. 

 "Observations on Geological Structure of Valley of the Mississippi; Jour. 

 Acad. Sci. Philadelphia, Vol. II. pp. 14-52, 1821. 



•Jour. Acad. Nat. Sci. Philadelphia, Vol. II, pt. i. p. 14, 1821. 



