CONTENTS 
CHAPTER I. 
GENERAL REMARKS ON THE PHYSICAL GEOGRAPHY OP THE REGION EXPLORED. 
Page. 
Extent and boundaries of the region.—Mountain ranges.—Trend and elevation.—Table lands, their extent and 
elevation.—Llano Estacado.—Two slopes of the plain.—Altitude.—Bluff character of its northern borders.-— 
Limit of the Llano on the east.... 7—11 
CHAPTER II. 
GEOLOGY OP THE MOUNTAIN RANGES. 
Ranges probably granitic, with Carboniferous limestone.—Organ mountains.—Hueco mountains.—Los Cornu- 
dos.-—Polished rocks.—Guadalupe mountains.—Trend towards the Witchita mountains.-—Sierra de los Alamos 
and Los Cornudos.-—Probable shallowness of the valleys in the granite.—Natural tanks or reservoirs of water.— 
Similar tanks in the African deserts.—Probable origin. 12—15 
CHAPTER III. 
GEOLOGY OP THE LLANO ESTACADO AND THE PLATEAUX BETWEEN THE MOUNTAIN RANGES PROM 
THE RIO GRANDE TO THE COLORADO. 
Horizontal character of the strata of the Llano.—Section of the strata.—Absence of bluffs.—Character of the 
strata underlying the Llano.—Gypsum and red clays.—Probable Cretaceous age of the upper strata of the 
Llano.—Fossils.-—Cretaceous at Dona Ana.—Possible presence of Tertiary strata.—Absence of Jurassic fossils.— 
Red sandstone and Gypsum formation of Delaware creek and the Pecos.—Gypsum of the Andes and of Iowa.— 
Of Nova Scotia and Virginia.-—Of Tuscany, Italy.—Extent of the American formation.—Geology of the plains 
between the Rio Grande and the Guadalupe mountains.-—Sand-hills.—Saline lakes.—Springs.—Artesian wells 16—23 
CHAPTER IV. 
REMARKS ON THE GEOLOGY OF THE ROUTE, PROM THE LLANO ESTACADO TO PRESTON. 
General description of the country.—Red sandstone and gypsum.—Age of the Gypsum formation.—Absence of 
fossils.—Probable Cretaceous or Carboniferous age.—Gypsum of Nova Scotia in the Carboniferous.—Fort Belk¬ 
nap to Preston.—Section of strata at Belknap.—Coal.—Carboniferous limestone.-—Cross timbers.—Cretaceous.-— 
Loess.. 24—28 
CHAPTER V. 
BUILDING -STONE. —COAL. —GYPSUM. —LEAD. —SULPHUR. 
1. Building-stone. —Description of the principal specimens in the collection.—Remarks upon them and their 29—30 
distribution_______ 
2. Coal.—F ort Belknap.—Carboniferous formation.—Lignite on the Brazos.—Probable extent of the coal-.. 31—32 
3. Gypsum.—G eneral description of the mineral.—Its composition and uses.—Anhydrite.—Varieties of gypsum in 
the collection.—Description of a specimen containing carbonate of lime.—Gypsum of Plaister Cove, N. S.— 
Applications of gypsum in the arts.—Quantity mined and shipped to the United States.—Remarks on the origin 
and formation of the beds.—Gypsum in the Tertiary strata of California----.-. 32—36 
4. Lead.— Lead and silver mines of the Organ mountains.—Description of the specimens.—Galena.—Cerusite 36—38 
5. Sulphur.— Analysis of a dry powder from Delaware creek. 38 
