Geological Observations on South America
Although in some respects more technical in their subjects and style than Darwin’s “Journal,” the books here reprinted will never lose their value and interest for the originality of the observations they contain. Many parts of them are admirably adapted for giving an insight into problems regarding the structure and changes of the earth’s surface, and in fact they form a charming introduction to physical geology and physiography in their application to special domains. The books themselves cannot be obtained for many times the price of the present volume, and both the general reader, who desires to know more of Darwin’s work, and the student of geology, who naturally wishes to know how a master mind reasoned on most important geological subjects, will be glad of the opportunity of possessing them in a convenient and cheap form.
The three introductions, which my friend Professor Judd has kindly furnished, give critical and historical information which makes this edition of special value.
G.T.B.
Of the remarkable “trilogy” constituted by Darwin’s writings which deal with the geology of the “Beagle,” the member which has perhaps attracted least attention, up to the present time is that which treats of the geology of South America. The actual writing of this book appears to have occupied Darwin a shorter period than either of the other volumes of the series; his diary records that the work was accomplished within ten months, namely, between July 1844 and April 1845; but the book was not actually issued till late in the year following, the preface bearing the date “September 1846.” Altogether, as Darwin informs us in his “Autobiography,” the geological books “consumed four and a half years’ steady work,” most of the remainder of the ten years that elapsed between the return of the “Beagle,” and the completion of his geological books being, it is sad to relate, “lost through illness!”
Concerning the “Geological Observations on South America,” Darwin wrote to his friend Lyell, as follows:—“My volume will be about 240 pages, dreadfully dull, yet much condensed. I think whenever you have time to look through it, you will think the collection of facts on the elevation of the land and on the formation of terraces pretty good.”
Charles Darwin
Geological Observations on South America
CONTENTS
SOUTHWARD OF THE PLATA.
DIAGRAM 1. SECTION OF STEP-FORMED PLAINS SOUTH OF NUEVO GULF.
(DIAGRAM 2. SECTION OF PLAINS IN THE BAY OF ST. GEORGE.
(DIAGRAM 3. SECTION OF PLAINS AT PORT DESIRE.
(DIAGRAM 4. SECTION OF PLAINS AT PORT S. JULIAN.
(DIAGRAM 5. SECTION OF PLAINS AT THE MOUTH OF THE RIO SANTA CRUZ.
THE VALLEY OF THE R. SANTA CRUZ.
TABLE 1.
TABLE 2.
A SUMMARY OF RESULTS.
GRAVEL FORMATION OF PATAGONIA.
FORMATION OF CLIFFS.
THE ISLAND OF CHILOE.
VALDIVIA.
CONCEPCION.
COAST NORTH OF CONCEPCION.
VALPARAISO.
VALPARAISO TO COQUIMBO.
COQUIMBO.
(DIAGRAM 8.—SECTION OF PLAIN OF COQUIMBO.
VALLEY OF COQUIMBO.
(FIGURE 10. NORTH AND SOUTH SECTION ACROSS THE VALLEY OF COQUIMBO.
(FIGURE 11. DIAGRAM OF A BAY IN A DISTRICT WHICH HAS BEGUN SLOWLY RISING)
COQUIMBO TO GUASCO.
COPIAPO.
LIMA.
FOSSIL-REMAINS OF HUMAN ART.
A SUMMARY ON THE RECENT ELEVATION OF THE WEST COAST OF SOUTH AMERICA.
SLOPING TERRACES OF GRAVEL IN THE VALLEYS OF THE CORDILLERA.
FORMATION OF VALLEYS.
SUPERFICIAL SALINE DEPOSITS.
THIN, SUPERFICIAL, SALINE INCRUSTATIONS.
SALT-LAKES OF PATAGONIA AND LA PLATA.
BUENOS AYRES TO THE RIO COLORADO.
BAHIA BLANCA.
BUENOS AYRES TO ST. FE BAJADA, IN ENTRE RIOS.
PHYTOLITHARIA.
BANDA ORIENTAL.
(FIGURE 16. SECTION OF THE LOWEST PLAIN AT PORT S. JULIAN.
A SUMMARY AND CONCLUDING REMARKS ON THE PAMPEAN FORMATION.
RIO NEGRO.
SAN JOSEF.
NUEVO GULF.
PORT DESIRE.
PORT S. JULIAN.
SANTA CRUZ.
BASALTIC LAVA OF THE S. CRUZ.
EASTERN TIERRA DEL FUEGO.
A SUMMARY ON THE PATAGONIAN TERTIARY FORMATION.
HUAFO.
CHILOE.
(FIGURE 19.)
VALDIVIA: ISLAND OF MOCHA.
CONCEPCION.
COQUIMBO.
COQUIMBO TO COPIAPO.
COAST OF PERU.
CONCLUDING REMARKS.
TABLE 4.
ON THE TEMPERATURE OF THE TERTIARY PERIOD.
RIO DE JANEIRO.
THE NORTHERN PROVINCES OF LA PLATA.
MONTE VIDEO.
SOUTHERN LA PLATA.
PATAGONIA.
PSEUDO-DIKES.
FALKLAND ISLANDS.
TIERRA DEL FUEGO.
WEST COAST, FROM THE SOUTHERN CHONOS ISLANDS TO NORTHERN CHILE.
CHILOE, VALDIVIA, CONCEPCION.
CENTRAL AND NORTHERN CHILE.
CONCLUDING REMARKS ON CLEAVAGE AND FOLIATION.
BASAL STRATA OF THE CORDILLERA.
PASSAGE OF THE ANDES BY THE PORTILLO OR PEQUENES PASS.
THE PORTILLO OR EASTERN CHAIN.
CONCLUDING REMARKS ON THE PORTILLO RANGE.
PASSAGE OF THE ANDES BY THE CUMBRE OR USPALLATA PASS.
THE USPALLATA RANGE.
CONCLUDING REMARKS ON THE USPALLATA RANGE.
VALPARAISO TO COQUIMBO.
COPPER MINES OF PANUNCILLO.
COQUIMBO: MINING DISTRICT OF ARQUEROS.
A SECTION EASTWARD, UP THE VALLEY OF COQUIMBO.
COQUIMBO TO GUASCO.
VALLEY OF COPIAPO.
SECOND AXIS OF ELEVATION.
THIRD AXIS OF ELEVATION.
FOURTH AXIS OF ELEVATION (VALLEY OF COPIAPO).
FIFTH AXIS OF ELEVATION (VALLEY OF COPIAPO, NEAR LOS AMOLANAS).
COQUIMBO.
GUASCO.
COPIAPO.
SIXTH AXIS OF ELEVATION (VALLEY OF COPIAPO).
SEVENTH AXIS OF ELEVATION.
VALLEY OF THE DESPOBLADO.
(FIGURE 24.)
ON THE ERUPTIVE SOURCES OF THE PORPHYRITIC CLAYSTONE AND GREENSTONE LAVAS.
IQUIQUE, SOUTHERN PERU.
METALLIFEROUS VEINS.
NOTE.