RESUME AND FIELD NOTES. 
129 
rouge, eouleur de vin un peu sableux, se trouve 
un schiste sableux, blanc etquelques concretions 
blanches dans 1’argile rouge. Les couches 
paraissent horizontales, ou a peu pres. La 
topograpbie du pays est une prairie ravinee de 
30 a 80 pieds par des rnisseaux presque tons 
a secs et nous suivons le dos d’ane de la ligne 
de partage des eaux entre Walnut et Canadian 
et Washita rivers. 
23 Aout.—Du No. 22 au No. 23.—On suit 
les memes argiles, sableuses, rouges, eouleur 
de vin au sommet d’un des mamelons, ces 
argiles rouges sont couronnees par un calcaire 
sableux, rouge, brecliiform passant a un gres 
rougeatre, bien stratifie, les couches plongeant 
a Louest seul, sous un angle de 5 a 10 de- 
gres. Pas d’alluvions. Des efflorescences alumi- 
neuses et saliferes dans une marne. Au camp 
ces marnes deviennent tellement sableuses que 
e’est un veritable gres rouge, avec un gres gris 
alternant. 
24 Aout.-—Du No. 23 au No. 24.—On suit 
constamment l’argile rouge qui est un peu 
moins sableuse que precedemment, aussi on 
traverse desruisseaux qui ont de l’eau courante. 
Pas d’alluvion. 
25 Aout.—Du No. 24 au No. 25.—On voit 
sans interruption les argiles rouges sableuses, 
passant dans gres rouges tres-fins, et calcaire 
silicieux rouge. Pas d’alluvion. 
26 Aout.—Dio No. 25 auNo. 26.—Les argiles 
rouges avec gres de meme eouleur sont tou- 
jours en vue. A moitie chemin on a des allu¬ 
vions tres sableuses avec cailloux de quartz, 
serpentine, trap, agate, jaspe variant de la 
grosseur d’une noissette a celle du poing toutes 
tres-roulees, epaisseur de cette alluvion de 1 
a 1^ pied. Le sable est blanc; on y trouve 
deux ou trois fragments de gypse. 
27 Aout.—Du No. 26 au No. 27.—On a 
constamment les marnes rouges, mais on com¬ 
mence de plus a y trouver quelques fragments 
de gypse, blanc ros tre amorphe, et un peu 
crystallin, il est sous forme de gateau ou bis¬ 
cuit. La meme alluvion qu’ hier. 
28 Aout.—Du No. 27 au No. 28—On a 
17 t 
as the fist. Under this red clay, of a wine- 
color, and somewhat sandy, we find white ar¬ 
gillaceous and arenaceous shales, and in the red 
clay some white concretions. The beds appear 
to be horizontal, or nearly so. The topogra¬ 
phy of the country is a prairie, cut by ravines 
from twenty to eighty feet deep. The courses 
of brooks now nearly all dry. We followed 
the water-shed or dividing ridge between the 
Walnut and Canadian and Washita rivers. 
August 23.— From Camp No. 22 to Camp 
No. 23.—We followed the same red or wine- 
colored sandy clays. At the summit of one 
of the small knolls these red clays are crowned 
by a sandy, red, brecciated limestone, passing 
into a reddish-grey sandstone, well stratified, 
and dipping to the southwest at an angle of 
from five to ten degrees. No alluvial deposites. 
Some efflorescences of salt and alum were found 
in the marls. At camp these marls became so 
sandy that they form a true red sandstone, 
with an alternation of grey. 
August 24.— From Camp No. 23 to Camp 
No. 24.—We constantly follow the red clay, 
which is a little less sandy than before. We 
cross brooks with running water. No allu¬ 
vium. 
August 25.— From Camp No. 24 to Camp 
No. 25.—We followed without interruption 
the red and sandy clays, passing into a very 
fine red sandstone, and into a red silicious 
limestone. No alluvium. 
August 26.— From Camp No. 25 to Camp 
No. 26.—Ked clays, with sandstone of the same 
color, are always in view. Half-way we find a 
very sandy alluvium, with pebbles of quartz, 
serpentine, trap, agate, and jasper, varying 
from the size of a nut to that of the fist, all of 
them much rounded and water-worn. The 
thickness of this alluvium is from one to one 
and a half feet. The sand is white. We found 
fragments of gypsum. 
August 27.— From Camp No. 26 to Camp 
No. 27.—We constantly find red marls, but 
fragments of gypsum make their appearance ; 
they are of a rosy-white color ; amorphous 
and occasionally somewhat crystalline, and 
having a form like a cake or biscuit. Allu¬ 
vium the same as yesterday. 
August 28.— From Camp No. 27 to Camp 
