Succession of the Ozark Series. — Xason. 143 
this sandstone from dozens of others which might occur. Much 
less are they sufficient data upon which to base an important 
geological division. 
Farther, every report which was obtainable was carefully 
searched by the writer for a full description of not only the 
First sandstone, but of the Second and Third sandstones. The 
search was fruitless, except for the following. Mr. Shuruard 
in describing the saccharoidal First sandstone in St. Genevieve 
county, says : 
This important formation consists of white and ferruginous sandstone, 
oocurring usually in massive beds. Its lithological and chemical char- 
acters in this county have been fully described by Dr. Litton, in the 
Second Annual Report (Part II, page 85). 
For the benefit of those who may not have access to the 
above report, I quote verbatim the "lithological and chemical 
characters" so "fully described" by Dr. Litton: 
I mention now as existing in the greatest abundance, and sufficient 
to supply the wants of the Union, a remarkably pure sandstone, found 
in the neighborhood of St. Genevieve, Plattin Rock and other places. 
This constitutes what is denominated saccharoidal sandstone, and is, in 
many places, almost snow-white, in beds easily approached and of vari- 
able thickness. This sandstone separates the upper from the second 
magnesian limestone, and about eight miles from St. Genevieve there is 
an exposure of it, from twenty to twenty-five feet high. It is unusually 
white, crumbles easily upon a slight pressure, is made up of rounded 
grains, and has little, if any, cementing substance to unite the parti- 
cles. It does not color in the least by heating; and, so far as I could 
discover, does not contain any material that, by oxidation, would color 
the glass made from it. It is, and has been, extensively quarried, and 
packed in barrels, is shipped from St. Genevieve and Plattin Rock to 
various points. Two analyses of this — number one by fusion with car- 
bonate of soda, and number two by treating with hydrofluoric acid, gave : 
1. 2. 
Silica 98.81 99.02 
Lime 0.92 0.98 
The above has been quoted in full from the description re- 
ferred to by Mr. Shumard, in order that perchance the reader 
may discover some subtle but distinguishing characteristic 
which has escaped the writer, but by which the authors re- 
ferred to were able to recognize unmistakably the First sand- 
stone when they saw it. One, at least, of the above mentioned 
observers seems to have had difficulty in this respect, for in- 
stead of saying the sandstone observed in Moniteau county is 
the First sandstone, he says, "the rock I have st<i>i><>si<l to be 
