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the intestises^ as it were, of the rocks are revealed to sight and
search.

Forming the pediment of this stupendous mural escarpment
is the second brim or bench (being the lowest) in the general
mountain descent Here the approaching elevation of the plain,
the increase in size of the streaiins, the accumulating debris from
above, and the increased atmospheric abrasion, all unite to oblit-
erate the angularity of the rocKs and impair Uie striking dis-
tinctness of formation. Forests of pine and deciduous trees
prevail. The flora and vegetation is abundant and various.
The atmospheric irrigation becomes uncertain, and the rocks are
covered with soil or the fragments of their own superficial de-
struction. Immediately following is the broad space occupied
by die fusion of the mountain base and the plain gently descend*
ing to meet it Here is a profile infinitely indented and bro-
ken ; alternately the sloping ridges protrude their ribs into the
plain, and the plain advances its valleys between them to re-
ceive the streams. This is the region of the placers, where is
checked in its descent and lodged beneath the alluvian soil
the free gold washed down by torrents from the overhanging
summits.

This sketch of the normal structure and configuration of the
Cordillera is illustrated by a chequered list of details in its
minute elements. The primeval rocks, heated to incandescence,
rest in their vertical positions unaltered fix>m their original form ;
they have been roasted but not liquified. Original strata of lime-
stone and gypsum, uplifted on high but not destroyed, rest upon
the summit as a torn hat. Gvpum, limestones, slates, clays,
shales, are thus found near the highest summits. The decay of
the secondary rocks gives extraordinary fertility to the moun-
tain flanks and to the alluvial bottoms below. Mence the luxu-
riance of the arborescenoe, the pastures, and the flora. The alti-
tude of the summits gathers and retains the snows, whose gla-
ciers give birth to innumerable rivers. These gash the precipi-
tous &nks with chasms, up which roads ascend ; the composi-
tion of the rooks is here revealed ; the mysteries of their mte-
rior contents are unravelled, and the secretions of nature sub-
jected to the human eye and hand.

Thus, then, erects itself the primeval Cordillera, constructed
of horizontal plates, vertically thrown up by stupendous vol-
canic forces, partially altered or roasted by mcandescent heat, but
neither destroyed nor recast in form ; the secondary rooks are



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858 Parks of Colorado.

tossed and scattered high in the upper regions, but are not cal«>
cined by flame. The metallic ores are as various as is the variety
of the rocks, enriched by heat and exposed by upheaval and cor-
rosion. No lava, no pumice, no obsiaien, nothing of melted mat-
ter from the plutonic region is seen. This furrowing of the ter-
restrial crust has alone occupied and exhausted the stupendous
volcanic throes of the subterranean world of fire.

Sierra Mimbres. — The Sierra Mimbres, forming the western
envelope of the park, is not dissimilar to the Cordillera in its
origin, composition, and configuration. Rising from the level of
the great plateau, it is of inferior bulk and rank. It forms the
backbone from whose contrasted flanks descend the waters of
the Bio del ITorte on the east, and of the Colorado pn the
west.

Craters of extinct volcanoes are numeroas ; streams of lava,
once liquid, abound ; pedrigals of semi-crystalline basalt sub-
merge and cover the valleys into which they have flowed, and
over which they have hardened.

This Sierra, then, has a general direction from north to south,
corresponding with the 109th meridian. It has all the charac-
teristics in mmiature of the Cordillera, but is chequered and in-
terrupted by the escape of subterranean fires, having areas over-
flowed and buried beneath the erupted current Where the nas-
cent springs of the Bio del Norte have their birth, the Sierra
Mimbres culminate to stupendous peaks of perennial snow, lo-
cally named Sierra San Juan.

The concave plain of the San Luis park, begirt by this ellip-
tical zone of the Sierras, thus cappea with a ragged fringe of
snow projected upward against the canopy, is the receptacle of
their converging waters. It is a bowl of vast amplitude, which
has for countless ages received and kept the sedimentary settlings
of so prodigious a circuit of Sierras, builded up with even^ va-
riety of form, structure and geological elements elsewhere found
to enter into the architecture of nature. Hither descend the
currents of water, of the atmosphere, of lava. The rocks rent
from the naked pinnacles, tortured bv the intense vicissitudes
which assail them; the fragments rolled by the perpetual pres-
sure of gravity upon the descending slopes ; the sands and soils
from the foundations of rocks and clays of every gradation of
hardness ; the humus of expired forests and annual vegetation ;
elements carbonized by transient fires ; organic decay ; all these
elements descend, intermingle, and accumulate.

This concave plain is, then, a bowl filled with sedimentary
drift, covered with soil and varnished over as it were with vege-
tation. The northern department or Bincon, closely embraced
by the Sierras and occupied by the San Luis lake, is a vast sa-



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Parks of Colorado. 859

vanna deposited from the filtration of the waters, hiehlj impreg-
Dated witn the mountain debris. Beneath this soil is a contin-
uous pavement of peat, which maintains the saturation of the
super-soil, and is aamirable for fuel.

The middle region of the plain, longitudinally, displays a cra-
ter of the most perfect form. The interior pit has a diameter
of twenty miles, from the cenjer of which is seen the circum-
ferent wall forming an exact circle, and in height five hundred
feet. This wall is a barranca, composed of lava, pumice, calcined
lime, metamorphosed sandstone, vitrified rocks, and obsidien.
This circumferent barranca is perforated through by the entrance
and departure of the Bio del Norte, the Calebra, and the Cos-
tilla rivers, which traverse the northern, western and southern
edges of the interior. By this and other forces of corrosion this
barranca is on these three sides cat into isolated hills, called cer-
ritos, of every fantastic form and of extraordinary beauty of
shape and tints. The bottom of the crater has been filled up
with the soils resulting from the decay of this variety of ma-
terial, introduced by the currents of the water and of the atmos-
Ehere. It is beveled by these forces to a perfect level ; is of the
ittest fertility, and drained through the porous formation which
underlies it.

From this crater to its southern rim, a distance of sixty-five
miles, the park expands over a prodigious pedrisal formed from
it in the period or volcanic activity. This pedrigal retains its
level, and is perforated by the the Rio del Norte, whose longitu-
dinal course is confined m a profound chasm or cafLon, of per-
pendicular walls of lava, increasing to the depth of 1,200 feet,
where it debouches from the jaws of this gigantic flood of lava,
near the village of La Joya, in New Mexico. Such are the ex-
traordinary forms and stupendous dimensions with which nature
here salutes the eye and astonishes the imagination. The ex-
pansion of the lava is all to the south, following the descent
toward the sea. Toward the north, repelled by the ascent, are
waves demonstrating the defeated effort to climb the mountain
base.

Such is an imperfect sketch of this wonderful amphitheater
of the Sierras. Its physical structure is infinitely complex, ex-
hibiting all the elements of nature piled in contact, yet set to-
gether in order and arranged in harmony ; its cloud compelling
Sierras, of stern primeval matter and proportions; its concave
basin of fat fertility ; its atmosphere of dazzling brilliancy, tonic
temperature, and gorgeous tints ; its arable and pastoral excel-
lence, ffrand forests, and multitude of streams ; its infinite va-
riety of mines and minerals, embracing the whole catalogue of
metals, rocks, clays and fuel ; its capacity to produce grain, flax,



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360 Parks of Colorado.

wool, hides, yegetables, fruits, meats, pooltrj, and dairy food;
the compact economy of arrangement which blends and inter-
fuses all these varieties; these combine to provoke, stimulate^
and reward the taste for physical and mental labor.

Entrance and exit over the rim of the park is everywhere
made easy by convenient passes. Boads re-enter upon it from
all points of the compass and eK^rj portion of the surrounding
continent. These are not obstructed at any season. -On the
north is the Poncho pass, leading to the Upper Arkansas river,
and into the south park. On the east, the Mosca and Sangre de
Christo passes debouch immediately upon the great plains. On
the south is the channel of the Bio del mrte. On the west easy
roads diverge to the rivers Chamas, San Juan, and towwl Ari-
zona. In the northwest the Oocha-to-pee opens to the great
Salt Lake and the Pacifia Convenient thoroughfares and excel-
lent roads converge from all points and diverge with the same
fiu^ility.

The system of the four parks, extending to the north, indefi-
nitely amplifies and repeats all that characterizes the San Luis
park. Smaller in size and less illustrated by variety, each one
of the three by itself lingers behind the San Luis, but is an
equal ornament in the same family. Their graceful forms, their
happy harmony of contact and position, make their aggregated
attractions the fascinating charm and glory of the American con-
tinent.

The abundance and variety of hot springs of every modula-
tion of temperature is very great. These are also equalled by
waters of medicinal virtues. It has been the paradise of the
aboriginal stock, elsewhere so abundant and various. Fish,
waterfowl, and birds of game and song and brilliant pluma^
frequent the streams and groves. Animal life is indefinite m
quantity and abundantly various.

The atmospheric currents which sweep away every exhalation
and all traces of malaria and miasma have an undeviating rota-
tion. These currents are necessarily vertical in direction and
equable in force, alternating smoothly as land and sea currents
01 the tropical islands of the ocean. The silence and serenity
of the atmosphere are not ruffled ; the changing temperature
alone indicates the motion of nature.

All around the elliptical circumference of the plain, following
as it were its shore, and bending with the indented base of the
mountain, is an uninterrupted road of unparalleled excellence.
This circuit is five hundred miles in length, and is graced with
a landscape of uninterrupted grandeur, variety and beauty ; on
the one hand the mountains, on the other hand the concave
plain, diversified with groves of alames and volcanic cerrito8«
At short intervals of five or ten miles asunder are crossed the



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Parks of Colorado. 361

swifk-running current and fertile meadows of the converging
mountain streams. Hot springs mingle their warm water with
all these streams, which swarm with delicate fish and waterfowl.

The works of the beaver and otter are everywhere encoun-
tered, and water power for machinery is of singularly universal
distribution. Agriculture classifies itself into pastoral and ara-
ble ; the former subsisting on the perennial grasses, the latter
upon irrigation everywhere attained by the streams and artificial
acequias. This concave configuration and symmetry of struc-
ture is remarkably propitious m economy of labor and produc-
tion, favored by the juxtaposition and variety of material, by
the short and easy transport, and by the benignant atmosphere.

The supreme excellence of position, structure, and productions
thus grouped within the system of the parks of Colorado, occu-
pying the heart of the continental home of the American peo-
ple, is conclusively discemable. Here is the focus of the moan-
tains, of the great rivers and of the metals of the continent.
The great rivers have here their extreme sources, which inter*
lock and form innumerable and convenient passes from sea to
sea. From these they descend smoothly to both oceans by con-
tinuous gradations. The parks occupy the line of the fortieth
degree, and offer the facilities for a lodgement in force, at the
highest altitude, where the highest divide of the continent ex-
ists, half way between the trough of the Mississippi and the Pa-
cific shore. Being immediately approachable over the great
plains their mines of precious metals are the nearest in the
world to the social masses of the American people and to their
great commercial cities. Their accessibility is perfect. All the
elements of a perfect economy, food, health, geographical posi-
tion, innumerable mines of the richest ores and every variety,
erect, assist, and fortify one another.

The San Luis park has twenty-four thousand population.
These people are of the Mexican- American race. Since the con-
quest of Cortez, A. D. 1520, the Mexican people have acquired
and adopted the language, religion, and in modified forms the
political and social systems of their European rulers. A taste
for seclusion has always characterized the aboriginal masses,
heightened by the geographical configuration of their peculiar
territory. Upon the plateau elevated seven thousand feet above
the oceans, and encased within an uninterrupted barrier of snow,
reside nine millions of homogeneous people. An instinctive
terror of the ocean, of the torrid heats and malarious atmos-
phere of the narrow coasts on either sea, perpetually haunts the
natives of the plateau. To them navigation is unknown and
marine life is abhorrent The industrial energies of the people
always active and elastic, and always recoiling from the sea,
have expanded to the north, following the longitudinal direction

▲x. JouB. SCL— Sboomb Bnnu, Vol. XLTV^No. 18S.^Noy., 1807.
42



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362 O. C Marsh on Ledererite from Nova Scotia,

of the plateau, of the mountains, and of the great rivers. This
column of progress advances from south to north ; it has reached
and permanently occupies the southern half of the San Luis park.

At the same moment the column of the American people ad-
vancing in force across the middle belt of the continent, from
east to west, is solidly lodged upon the eastern flank of the Cor-
dillera, and is everywhere entering the parks through the passes.
These two American populations, all of the Christian faith, here
meet front to front, harmonize, intermarry, and reinvigorate the
blended mass with the peculiar domestic accomplishments of
each other.

The Mexican contributes his primitive skill, inherited for cen-
turies without change, in the manipulations of pastoral and
mining industry, and in the tillage of the soil by artificial irri-

5[ation. The American adds to these machinery and the intel-
igence of expansive progress. The grafted stock has the sap
of both. As the coming continental railroad hastens to bind
together our people isolated on the seas, a longitudinal railroad
of 2,000 miles will unite with this in its middle course, bisecting
the Territory, States and cities of 10,000,000 of affiliated people.
This will fuse and harmonize the isolated peoples of our conti-
nent into one people, in all the relations of commerce, affinity
and concord.
Sfta Loui0 di OaLebra, July 6, 1866.



Art. XXXVIII. — Oontribtdions to the Mineralogy of Nova
Scotia ; by Prof. 0. C. Marsh, of Yale CoUege.— No. 1.
Ledererite identical with Omdinite.

During their first geological excursion to Nova Scotia, in
1827, Dr. 0. T. Jackson, and the late Francis Alger, Esq., dis-
covered a mineral at Gape Blomidon which has since been the
subject of no little discussion among mineralogists.* These
authors apparently regarded it from the first as a new species, but
other authorities differed widely as to its true nature. Mr.
Brooke of London, after measuring the angles of a crystal, pro-
nounced it to be apatite, a view subsequently controverted by
M. Dufr^noy of Paris, while Dr. Torrey of New York consid-
ered it nepheline.

Dr. Jackson subsequently described the mineral under the
name Ledererite, in honor of Baron von Lederer, then Austrian
Consul at New York;t and in the same paper Dr. A. A. Hayes,
gave the results of an analysis he had made, on which its claims

* Memoirs Am. Acad., yoL L p. 253.
f This Journal, yoL xzy, p. 78.



I



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O. C. Marsh on Ledererite from Nova Scotia. 303

to be coiisidered a difitinct s^ies were mainly founded. The
mineral examined had a specific gravity of 2169; and its com-
position, according to this analysis, was as foUows: —

Silica, 49-47

Aluminay 21*48

Lime, 11-48

Soda, 3-94

Phosphoi-ic acid, 3*48

Oxyd of iron, 0-14

Foreign matter, -03

Water, 8-58

98-60
The large amonnt of phosphoric acid, and the small percent-
age of water obtained, although the determination of the lat-
ter was not entirely satisfactory, left the true character of this
mineral still a matter of doubt. Berzelius attempted to clear
up the difficulty by proposing a formula, based upon Dr. Hayes's
analysis, according to which the mineral would consist of tiiree
atoms of lime-analcime and one of apatite.^

This view was adopted by Mr. Alger, who suggested also that
the crystalline form of the analcime mi^ht have been changed
to a hexagonal prism by the phosphate of limcf Bammelsl^rg
proposed to reject the phospnoric acid as an impurity, and with
it an amount of lime sufficient to form tribasic phosphate of
lime. This would leave a silicate differing from chabazdte in
having one-third the amount of water, and hence a lime-anal-
cime.| The probable identity of Ledererite with GmeUnite ap-
pears to have been first suggested by the editors of the London
and Edinburgh Philosophical Magazine in 1834;§ and Prof.
Shepard, in Ms Mineralogy of 1835, and Prof. Dana, in his first
edition in 1837, place it under that species. This view was
subsequently accepted by both Mr. Alger and Dr. Jackson.||
Finally Descloizeaux, in his Manuel (1862), published meas-
urements of crjrstals by himself which sustain it.

Although the identity of Ledererite and Gmelinite was thus
rendered highly probable, the chemical proof was still wanting,
and it was very desirable to obtain more of the mineral for fur-
ther investigation. At the request of Mr. Alger, the writer
made a careiul search for it at Gape Blomidon during several
visits to Nova Scotia, but without success until the summer of
1861, when a number of crystals were found near the original
locality, which had long b^n supposed to be exhausted. This
was on the north coast of Cape Blomidon, at a point nearly op-

* Jahresbericht, ziy, 1*76. f Alger'e PhiUipp's Mineralogy, p. 630.

1 Haadwdrteibnch, yoL i, p. 387. f YoL iy, p. 394.
I Boston Soc Kat Hist Journal yoi. y, p. 306.



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364 O. O. Marsh an LedereriU from Nova Scotia.

posite Cape Sharp. The ciystalB were found in geodes in ihe
amygdaloid, accompanied by analcime and quartz, and in most
instances implanted upon the latter subetanoe. They were snb-
sequently shown to Mr. Alger, who pronounced ihem identical
with the Ledererite discoyered by hunself and Dr. Jackson.

The crystals were from one-tenth to one-third of an inch in
diameter. Some of them, especially the smallest, were color-
less, and nearly transparent; others were yellowish-white or fiunt
salmon-red, and translucent. All were in the form of short
hexagonal prisms with pyramidal terminations, as shown in
the accompanying figures, that represented in fig. 1 bdng
the typical form. In all the crystals observed the sides of
the pnsms were marked with horizontal strice, while the planes
of the pyramids were striated parallel to weir polar edges.
These strisB were in most instances much more distinct l£an
those seen occasionally on cirstals of Gmelinite fix>m Irish lo-
calities, or from Iceland. Tnere'was, moreover, in most of the
specimens a tendency toward a rhombohedral form, as seen
in the much greater prominence of alternate pyramidal planes,
a peculiarity rarely observed hitherto in Gmehnite. In several
01 the cryBi»l8 this resulted in the form given in fig. 2.





As the amount of the mineral obtained was sufficient for a
chemical examination, the writer, while a student at Heidelbog
in 1863, made two analyses of it in the laboratory, and under
the direction of Prof. Bunsen.

An attempt was first made to decompose the finely powdeied
mineral with hydrochloric acid, but without success, alihoiigii
continued over the water-bath for forty-eight hours. A second
trial was made in the same way with sulphuric add, but strai^p
to say, the mineral was apparently litue affected. In conse-
quence of this unexpected difficulty, a portion of the mineral
which remained was decomposed by hydrofluoric acid, accord*
ing to Brunner's method, and the constituents, as given below
in analysis Ko. 1 &, separated in the uaual manner. A Ihiid
portion of the mineral was first used for a determination of



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O. C. Marsh on Ledererite from Nova Scotia. 365

the water, as given in No. la, and then filsed with carbonate
of soda, and its silica separated. A portion of the same min-
eral, but from a neighboring locality on Cape Blomidon, was also
decomposed by fusion with carbonate of soda, and its com]^
sition, as given in analysis No. 2, determined in accordance with
the usual methods. The amount employed in each analysis
was one gram. The specific gravity of the mineral used in
No. 1, was 2*108 ; in No. 2, 2*099, and the hardness in each
case was about 4*5. The omer physical, and the pyrognostic
characters of the mineral, corresponded essentially with those
observed in typical GmeUnite. The results obtained in the
analyses were as follows : —

L a

a b

Silica, 63-71 .... 61-82

Alumina, 17*68 18*46

Lime, 6*62 6*40

^\:::::::::: ,Z {^y-'-''

Phosphoric acid, . . . trace ....

Water, 17*98 .... 20*36

99*74 100.00

On comparing these results with those obtained by Dr.
Hayes in his analysis, the only one previously made of Leder-
erito, it will be seen that they differ widely in respect to the
amount of phosphoric acid ana water— the two important points,
in fact, which had occasioned discussion as to the nature of the
mineral. It should perhaps, be added that in consequence of
this discussion, special precautions were taken to guard against
error in detamimng these substances. The small amoimt of
material at command, rendered it impossible to repeat the analy-
ses; but the results of those completed make clearly evident,
what has long been suspected, that the phosphoric acid, found
by Mr. Hayes, must be regard^ as an impurity, and that Led-
ererite has essentii^y the same amount of water as Gmelinite,
and hence is identical with that species. The evidence of this
identity becomes still more apparent on comparmg the compo-
eition of the Cape Blomidon mineral, deduced indirectly from
a calculatibn of its constituents as given below, with the re-
sults obtained in analyses of typical Gmelinite.

The excess of silica obtainea, especially in the first analysis,
taken in connection with the remarkable difficulty of decompo-
sition, naturally suggested the presence of impurities in the
mineiBl; and, on examining with the microscope some frag-
ments of a nearly colorless crystal, a quantity of minute crys-



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366 O. C. Marsh on Ledererite from Nova Scotia.

tals of quartz difiseminated tbrougli the mass were detected.
Several other crystals from the same locality were eioimiiied,
and all found to contain quartz. This discovery clearly ex-
plained the large amount of silica obtained in analyzing the
mineral^ and also, perhaps, its resistance to decomposition.^

If, now, the results obtained in the above analyses be viewed
in the l^ht of this discovery, it is evident that the true compo-
sition of the mineral can only be ascertained from them by re-
jecting the quartz. Assuming, then, that the excess of silica
in the substance analyzed was due to quartz, — of which, indeed,
the microscopical examination afforded good evidence — and cal-
culating from analysis No. 1, first the oxygen ratios respectively
of the protoxyd bases, alumina, silica and water, they are
found to be, 278 : 8-24 : 2864 : 15-95, or veiy nearlv 1:3:



Online LibraryJohn AlmonThe American journal of science and arts → online text (page 93 of 102)