292 The American Geologist. May, 1901. 
beds of that part of the state, making extended collections es- 
pecially of what was afterwards designated as the Ripley 
Group of the cretaceous by Conrad * 
I also investigated closely the features and geological rela- 
tions of the "Orange Sand" (now better known as the La- 
fayette formation of the Southwest), showing its derivation 
partly from northern sources, partly from the underlying for- 
mations of which it contains the fossils ; distinctly characteriz- 
ing it as a quarternary deposit. 
It having become clearly apparent to me by this time that 
the survey would never maintain itself in public esteem on the 
basis of mineral discoveries, and that it must seek its main 
support in what services it might render to agriculture. I 
made a point of paying close attention to and recording the 
surface features, f vegetation, soils, the quality and supply of 
water, and especially the marls, which I found to occur in 
large supply and great variety. I also made a collection of 
plants, which, although omitted from the subjects mentioned 
in the act creating the survey, I perceived was essential to- 
ward the characterization of soils. In the prosecution of 
these studies, the close connection between the surface vege- 
tation and the underlying formations became so striking, that 
I soon largely availed myself of the former in tracing out the 
limits of adjacent formations, in searching for outcrops, etc. 
I also, by current inquiry among the inhabitants, ascer- 
tained all that was known regarding the peculiarities, merits 
and demerits of the several regions or soils, from an agricul- 
tural point of view, and studied their practice and its results 
on the several soils and crops. 
During the latter part of the season of 1856, I extended 
*A collection of fossils from these beds was sent to Conrad by Dr. Spill- 
man, of Columbus, to whom I had given a list of good fossiliferous localities 
of that group, of which he promptly availed himself. The same season 
(1850) in Conrad's published description of these fossils (Jour. Acad. Sci., 
Philadelphia, Vol. IV. N. S.. pn. 275 to 291.) Dr. Spillman is erroneously 
credited with being the discoverer of the Ripley beds. My original collection, 
containing a number of species still undescribed, was unfortunately never 
seen by Conrad, with whom I twice made arrangements for a protracted visit 
to Oxford for the purpose of studying the collections of the survey. His 
feeble health and subsequent death prevented the carrying-out of this pro- 
gram. 
tXo instrumental topographical work was ever done in connection with 
the Mississippi survey, partly because it was not provided for by law, partly 
because the continually recurring violent barometric changes during the work- 
ing season rendered the use of the aneroid, so useful elsewhere, very unsat- 
isfactory. The railroad levelings then available were, however, fully and 
extensively used by me. an., were excluded from the report of 1860. simply 
by the absolute need of brevity for the sake of I'educing the expense of pun- 
lication. 
