John Almon.

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ethylenic alcohols, which are nothing but the anhydrids of gly-
col, anhydrids formed bv the condensation of several molecules
into a single one. He has since 1862t applied to the hydrates
of silicic acid the same theory, by means of which he explained
the formation of polyethylenic compounds. Wurtz and Frie-
del:|: have shown tnat the theory of condensations is applicable
to acids as well as to alcohols, and several researches, among
others those of Hugo SchiflF,§ have confirmed this view. It re-
sults from this, that if, in order to take the most simple case, we
take the hydrate of silicium, corresponding to the chlorid, in
which the 4 atoms of chlorine are replaced by 4 equivalents of
the body HO,

OH



(1.) Si



3g = Si,4(eH).



We can derive from this hydrate, which with Odling we call nor-
mal, the following hydrates containing less water.
First, without conaensation :



• Bunetin da U Soci4t6 Cbimi<}ne, [1], i, 82; December, 1859.
' Repertoire de Chimie pure, ii, 449.
Ann. de CUm. et Phys., [8J. Iziii, 111 ; 1861



{Repertoire de Chimie pure, ii, 449.
Ann. de CUm. et Phys., [8], Iziii, 1
§ Oomptee Rendos de rAcademie dee Sciences, Ut, 1075; 1862.



Av. JouB. 3ci.~Skgond Sksibs, Vol. XLIII, No. 1S8.— Mabcu, 18C7.
23



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166 Friedel and Crafts on the Ethers of Silicic Acid.

( OH

(2.) lat anhydrid, SN O = si,0,2eH.

/en

The silicate which Odling calls metasilicate corresponds to this
hydrate.

Secondly, with condensation :

(OH
Si ^ OH

r OH

(3.) lat anhydrid, O = 2(SiO), 6(OH).

(OH
Si^OH
(OH

This hydrate is the type of Odling's intermediate silicates,
bodies which it would be better to call disilicates.

(OH

Si^OH

(4.) 2d anhydrid, O = 2Si, 20, 4(eH).

*]oH



Hi



OH

(5.) 3d anhydrid, O = 29i, 30, 2(OH).

O



^'JOH

Without giving other formulae of possible hydrates, we will
observe, that the three ethers of Ebelmen would come under
the case (1), (2) or (4) and (6). Ebelmen does not speak of any
ether corresponding to the formula (S), but this is tke only one
that we have been able to obtain in a state of purity, and every
repetition of Ebelmen's experiment has given negative results,
in spite of the most persevering efforts to prepare his bisilicate
and quadrisilicate.

Eexeihylic disilicic ether, — Having operated upon several pounds
of chlorid of siliciuro, and prepared large quantities of silicate
of ethyl with alcohol, which was not perfectlv anhydrous, a con-
siderable portion of the product boiled at a higher temperature
than the normal silicate. We collected all' the products of dif
ferent preparations, and on submitting them to a fractionated
distillation, we observed that a much larger amount of liquid
distilled at about 240°, than at any other point above or below
between 170° and 820°. In one preparation where 800 grama
of chlorid of silicium were employed, we obtained, beside the
normal silicate, 80 grams of a product boiling at 2S0°-240^. An
analysis gave:



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FViedel and Crafts on the Ethers of Silicic Acid. 167

L Substance, weight, .... 0*3860

€0-, 0-5940

HgO, 0-3100

Not succeeding well at first in obtaining a compound boiling
at a fixed temperature, we submitted all the products, whose
boiling point was higher than that of the normal silicate, to a
series of distillations in vacuo. This operation can be conducted
without difficulty, thanks to the tubes and corks of india-rubber
now manufactured,* and the labor of working the air-pump dur-
ing several days in succession was rendered much less disagree-
able by the employment of one of Bianchi's rotary pneumatic
machines, with the aid of which we could maintain an atmos-
phere exercising a pressure equal to only 3-5 millimeters of
mercury during all tne operations.

After eight fractionated distillations (pressure 3-5 mm.), the
product distilling at 126°-130° was analyzed.

11. Substance, weight, - - - . 0''7260

Silica, 0-2660

IIL SubaUnce, wt. (boiling point =126'-180**), 0-3675

€0,, 0-6690

H^O, 0-2970

This portion (125°-130° in vacuo), distilled in the air, passed
almost entirely at 238°-238^. An analysis of this gave :

IV. Substance, weight (boiling point 233"-238"), 0-1776

eOoy 0-2746

H^O, 0-1395

V. Substance, weight, .... 0-3760
SiOg, - - - - - - 0-2006

Theory.

L II. ra. IV. V VI. va 2Si, 6(€^H J, 70.

C, 41-96 42-22 42-16 42-11

H, 892 8-97 8-74 8*77

Si, 16-38 16-28 16-53 1669 16-38

All these numbers agree with the formula /£j h ? [^7'
which belongs to one of the ethers of disilicic aeid, if this name
be given to the hydrate, which results from the condensation of
two molecules of the normal hydrate with elimination of the
smallest quantity possible of water, i. e., one molecule.

The reaction which gives rise to the ether above analyzed is
expressed by the equation

* Yulcanized india-rubber becomes less pervious to air after it has been boiled
irith a weak solutiou of caustic potash stmciently long to extract most of the
aulphor.



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168 Friedel and Crafts on the Ethers of Silicic Acid.

As this ether, which may be named hexethylic disilicic ether,
was not obtained by Ebelmen, we have used great care in assur-
ing ourselves, that it is really a distinct compound, and rely as
Sroof upon the following facts. The boiling point after repeated
istillations remains constant at a temperature too remote from
that of the boiling points, which Ebelmen indicates for the nor-
mal ether and for his bisilicate, to make it possible to consider
it as a mixture of these two compounds. We succeeded in ob-
taining the ether almost pure by treating chlorid of silicium
with alcohol containing the requisite quantity of water. The
product of this experiment was distilled under a pressure of 3-5
mm., and distilled almost entirely at 126°-130°.

This product, boiling at 126''-i80° in vacuo, furnished the ma*
terial for the determinations of silica vi and Vii given above.

VI. Substance, weight, - - - . 0*7305
SiOj, 0-2685

VII. Substance, weight, ... - &370
SiO^, 0-8330

We thought afr first that the compound was decomposed by heat,
and that its boiling point changed after a large number of dis-
tillations in the air, and this indeed was the reason, that we un-
dertook the series of distillations in vacuo; but this idea proved
afterwards to be erroneous, for a portion, distilled in vacuo after
having been heated seven hours at 280^-285° in a sealed tube
did not change its boiling point. With silicic ethers as with the
chlorhydrines great care must be taken to exclude the moisture
of the atmosphere during the protracted operations necessary to
effect a large number of fractionated distillations, and if the
boiling points changed, it was because the ethers had been de-
composed by moisture.

The vapor density of hexethylic disilicic ether corresponds
with the formula given above. The first determination was
made with an impure product, and the number 13*5 instead of
11-86 was found ; but this only came from a portion of an ether
having a higher boiling point, which remained in the bulb.
This we satisfied ourselves of by making a determination of si-
licic acid of the liquid remaining in the bulb.

I. Substance, weight, - - , . 0*8875
SiOj, - 0-8205

Si=16'82 instead of 16-88, the theoretical number. If we sup-

Eose that the excess of silica came from an admixture of a body
aving the jcomposition of the bisilicate of Ebelmen, the liquid
remaining in the bulb must have contained one-tenth its weight
of that compound.

A second determi;iation made with a product redistilled seve-
ral times and boiling at 233°-234° gave 12025, a number which
corresponds very closelj with the theoretical 11-86.



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Friedel and Crafts on the Ethers of SiHdc Acid. 169

Difference between the weights of balb, 1*6595 gr.

Temperature of balance, - - - i2"-6

" " oiUbath (mercury thermom.), 206°

Height of barometer, - - * - 757-8 mm.

Capacity of bulb, 320 cc

Air remaining (measured), - - - 26 cc.
11^ temperature and 756*8 mm. barometric height.

A determination of ailica was made from the liquid remaining
in the bulb.

Substance, weight, - - 0*4670
SiOa, 0*1655

Si=16"48 ; theory=16-88. The density of the hexethylic di-
silicic ether is at 0° =:1-0196, at 19*'-2 =1-0019.

The ether is a colorless liquid of slightly oily consistency,
with a rather agreeable odor, scarcely differing from that of the
normal silicate. It burns with a smoke composed of silicic acid
like all of this class of compounds.

Aqueous alcohol transforms it into products having a higher
boiling point. It is not so easily acted on by moisture as the
normal silicate.

After we had demonstrated the existence of the above body
we attempted to obtain the bisilicate of Ebelmen in order to de*
termine whether it corresponds to the first anhydrid of silicic
acid or to the second anhydrid of disilicic acid, if this latter ex*
ists ; but all the experiments undertaken failed to give this body,
whose existence seemed so probable on theoretical grounds and
whose preparation seemed so easy according to the statements
of Ebelmen. We have submitted to a great number of frac-
tionated distillations in the air, under a diminished pressure and
in vacuo, the products boilipg above 240®, without being able to
observe any point, at which a particularly larce quantity distill-
ed ; and it will be seen by our analyses, that tne quantity of si-
licic acid contained in the higher products, was greater than that
required by theory for the bisilicate of Ebelmen. The temper-
ature also, which was measured in vacuo by a mercury tner-
mometer, corresponds to 450° in the air, a point much higher
than that at which Ebelmen supposed his compound to b^il. It
may be of \ise to give the results of our experiments as they
teach us something concerning the nature of the condensed sili-
cates containing more silicic acid than the ether just described.

In order to determine the difference in boiling point due to a
diminution of pression, and to ascertain what reliance could be
placed on the constan<*.y of boiling points in vacuo, we distilled,
under a pressure of 8-6 millimeters, the normal silicate of ethyl
having a fixed boiling point at 165°'5 in the air. Platinum wire
and a piece of charcoal were put in the flask to make the ebul-
lition as quiet as possible, but without any very marked ^eot



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170 Friedel and Crafts on the Ethers of SiKcic Acid.

The normal ether began to boil at 65^ and the thermometer rose
rapidly to 72^-73® and remained nearly stationary at this tem-
perature (in another experiment at 74°-75°) during the distil la*
tion. When the distillation was interrupted and recommenced,
ebullition commenced always at a much lower point than 73^
According to this, the diminution of pressure to 3^ mm. powers
the boiling point of the ether in question from 165°'5 to about
73**. We have seen that the hexethylic disilicic ether, which
distilled at 233^-8*', in the air distilled at 226°-230*' under a pres-.
sure of 3-6 mm. For this latter product, the limits of tempera-
ture within which the thermometer varies during a distillation
in vacuo, are much less than for normal ether.

The ebullition is much more regular under a somewhat greater
pressure, and for this reason and also because we hoped that the
change of pressure might facilitate the separation of the pro-
ducts, as Boscoe has observed in the case of hydrates of acids,
we made another series of distillations under a pressure of 60
millimeters of mercury.

These distillations were made with an apparatus which per-
mitted us to operate almost as rapidly as wnen distilling in the
air, and it onhr requires a small hand pump, when no better is
to be procurer




The opening B has an india-rubber tube through which is
passed the glass tube leading from the flask containing the sub-
stance. At C a thermometer is introduced in the same way.
The lower end, A, of the receiver has a tube, which is closed
during the distillation, and is opened to draw off the product
when required. It is not necessary to surround the receiver



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JK F. Hayden on the Cretaceous rocks of the West 171

with water, as the specific heat of the silicic ether is very
small. The opening D, which is closed with a piece of glass
rod fitting into an india-rubber tube, serves to ada a new quan-
titj of liquid when required. The object of the other parts of
the apparatus is obvious. The balloon at the extremity only
serves to augment the volume, so that a constant pressure may
be more easily obtained ; its communication with the distilling
apparatus is closed when it becomes necessary to open the latter.
All the connections were made with india-rubber tubes boiled
in potash, and used double, the inner one coated with tallow,
ana when the apparatus was left to itself the pressure only va*
ried a few millimeters in twenty-four hours, and could easily be
kept perfectly constant hj a few strokes of the air pump during
a aistillation. We will give the results of several series of dis*
tillations made with the same material under different pressures.

[To be concluded.]



Art. XVIII. — Bemarhs on the Oretaceous rocks of the West krwwn
as No. 1, or the Dakota Group; by F. V. Hayden.

The Cretaceous rocks of the Upper Missouri have been sep-
arated into five divisions, which have been designated, for the
sake of convenience, by Nos. 1, 2, 3, 4, and 6.* They have also
received special geographical names indicating points where they
are shown in their largest developmentf The Dakota group or
Formation No. 1, ^s at the base of this series, and either as an
outcropping or unaerlying rock extends over a large portion of
Nebraska, Dakota, Minnesota, Kansas^ and even reaches far
southward into New Mexico. It is more distinctively defined
along the Missouri river between Omaha City and the Big Sioux,
where it exhibits its typical characters.

The lithological characters of this group have been so often
described in former memoirs by Mr. Meek and the writer, that
they scarcelv need to be repeated here. The principal object
of this article is to present such additions to our knowltdge of
it as may have been obtained since our last papers were pub-
lished. It is not intended to discuss in detail any differences of
opinion, or to make any criticisms, but to present certain facts
and statements gathered by Professors Capellini and Marcou in
their tour to Nebraska in 1863, and the results of the investiga-
tions of Prof. Heer derived from the study of the flora of this
group.

* Memoin Am. Acad. Arts and Sci., toI. t, new series, also numerous papers bj
F. B. Meek and F. V. Hayden.

t Proceedings Acad. Nat ScL, Dec 1861.



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172 F. V. Hayden on the Cretaceous rocks of the West

In order that the geological relations of the Dakota group
may be better understood, I have given a brief summary of the
contiguous formations.

In ascending the Missouri river we find near Fort Leaven^
worth exposures of limestone which, up to the present time, we
have regarded as belonging to the upper Coal-measures. The
beds are all nearly horizontal, with a slight, almost impercepti-
ble, dip toward the northwest. As we continue up the Missouri,
layer after layer of these Coal-measure rocks pass from view be-
neath the water level of the river, and when we reach Fort Lisa
they have entirely passed from sight and are overlapped by a
bed of variegated friable sandstone. The sandstone undoubtedly
exists, or has existed, as an underlying rock considerably lower
down the river than Fort Lisa, probably nearly to Omaha City,
but has either been removed by erosion, or concealed by the great
thickness of superficial recent deposits which cover this country,
sometimes entirely hiding from view the underlying basis rocks
over large areas. Ascending the Platte valley we have the true
Upper Carboniferous limestone nearly to the mouth of the Elk-
horn. Before reaching that point, however, we observe a portion
of No. 1 resting directly upon the limestones, as the following
section will show.

1. Gray compact siliceous rock, passing down into a coarse
conglomerate, an aggregation of water-worn pebbles, cemented
with angular grains of quartz ; then a coarse grained micaceous
sandstone (lower portion of Dakota group), 25 feet.

2. Yellow and light gray limestone of the upper coal-meas-
ures containing numerous fossils, Spirifer ^imeratuSj Spiriaera
subtUita, Fusulina cylindrical ProductuSy ChoneteSj and abundant
coral and crinoidal remains."^

At the mouth of the Elkhorn, the Carboniferous limestones
have passed from view beneath the Cretaceous sandstones. The
intermediate Permo-carboniferous and Permian rocks, as well as
the variegated and gypsiferous marls and clays which are quite
conspicuous westward from Fort Eiley, are wanting in this region.
The Dakota group as seen along the Missouri passes beneath the
bed of the river about 80 miles above the mouth of the Big
Sioux. How far up the Big Sioux it extends is not yet known ;
but at a point 40 miles up the valley, the seam of earthy Lignite,
which is seen just above the Omaha reserve, crops out, and is
exciting some attention among the farmers.

The researches of Prof. Hall have extended this group north-
ward from the Missouri river into Minnesota 180 miles or more.
In an interesting memoir read before the American Philosophical
Society at Philadelphia, Prof. Hall, after describing numerous
exposures of the variegated quartzites from St. Peters to Fort

* Tnuu. Amer. Phil. Soc 1861.



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F. V. Hay den on ike Cretaceous rocks of the West. 178

Ridgely, says: "Proceeding westward from Fort Ridgely, I had
DO opportunity of seeing any other formation than the prairie
for about thirty miles. At this point near where we crossed the
Big Cottonwood Biver, there is an exposure of rock in the bank
of the stream ; and at a short distance farther on, some explora-
tions had been made for coal, and a shaft had been sunk to the
depth of more than one hundred feet The materials thrown
out of this shaft consisted of a dull greenish argillaqeous sand,
with calcareous nodules, together with irregularly laminated
sandstone containing vegetable remains. The order of deposits,
as given to me by Mr. Morin, who superintended a part of the
working, was as follows :

1. Ironstone; 1 ft. 6 inches.

2. Sand, clay, etc. ; 40 ft.

3. Earthy coal;^ 1 ft. 8 inches.

4. Sand, clay, etc. ; 8 ft.

5. Sandstone in irregular and diagonally laminated layers, with some-

times calcareous concretions, and containing plant remains ; 5 ft.

6. A Calcareous sandy clay of Tariable color and character ; 20 ft.

7. Sandstone in loose thin layers of three or four inches ; 4 ft.

8. Clay with coaly seams near the bottom; 16 ft

9. Clay ; 13 ft

10. Loose quicksand tt bottom of shaft.

" In the river bank, at a quarter of a mile distant, and at a
level 30 or 40 feet below the ground where the shaft began, there
is the following exposure :

1. Loose ironstonef in nodules and irregular concretions, more or less

mixed with drift and pebbles ; 1-2 ft.

2. Calcareous clay ; 6-8 ft

3. Earthy coal ; 8 inches.

4. Clay as above coal ; 4 inches.

5. Yellow or ferruginous sand and clay ; 8-8^ ft.

6. Ferruginous sandstone in irregular layers and diagonally laminated

to level of river; thickness unknown.

" This sandstone appears to be the sam^B as that containing the
vegetable remains met with in the shaft; and though I did not
find plants in it at this point, I was informed that specimens had
been found there ; and at another place on the Cottonwood I
found them to be quite common. Near the previous exposure,

* An analyBis of this ooal, by Prof. T. Sterry Haat, gave the following results :

Fixed carbon, 26*1

Volatile ** 26-7

Ash •' 48-2=100-0

In the tectioDs of strata near the mouth of the Redwood river, then^ is a stratum
of similar earthy ooal three f<»et thick.

f This ferruginoQS layer does not appear to belong to the regularly stratified
deposite, as it overliefl, irregularly* the eages of the succssBiTe beds, aira has been
depoeitflid after the denudation had taken place.
Am. Joub. Sgz.— Secokd Sbbibs, Vol. XLIU, No. 128.~March, 18ft7.
23



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174 F. V. Hayden an the Creiaceoui roeki of the West

and partly from an old digging, I obtained a simOar section*
At etill another point I noticed a similar exposare, leaving no
doubt of the character and order of arrangement of the materiala
composing this formation.

" The character of the vegetation obtained from the sandstone
of the shaft and elsewhere, resembling the leaves of Salix, Pop-
lar, Liriodendron, Tupelo, eta, induced me to refer this forma-
tion to the Cretaceous period. A single indistinct shell was
the only animal fossil I was able to obtain. In aspect the cal-
careous concretions are similar to those from the Cretaceoua
formation of the upper Missouri ; and the green argillaceous clay
is likewise similar.^'

At Redwood Falls, also, Prof. Hall obtained another section
of this group with a seam of earthy coal three feet in thickness.
There is little doubt that this group will be found extending far
northward, either as a continuous formation or in isolated
patches, perhaps even into the British possessions.

In September, 1863, Mr. Marcou and Prof Capellini of the
University of Bologt5a, Italy, made an excursion up the Missouri
river to a point near the mouth of the Big Sioux. It seems
that both or them studied with care the different geological for-
mations along the river under quite favorable circumstances.
Prof. Capellini made quite an extensive collection of fossil plants
at different localities, principally from Tekama, Blackbird Hill
and Big Sioux. These plants he placed in the hands of Prof
O. Heer of the University of Zurich, Switzerland, who described
them in a small but carefully prepared memoir with four plates,
4to. Mr. Marcou also published the results of his examina-
tions in the Bulletin of tne Geological Society of France. He
there acknowledges that the rocks, which have hitherto been in-
cluded in No. 1 or Dakota group are Cretaceous. Capellini and
Heer came to the same conclusion, and thus one disputed point
in regard to the geology of the West may be regarded as for-
ever set at rest. I would remark just here, that I have person-
ally examined the greater part of the territories of Kansas, Ne-
braska, Dakota, Montana, Idaho, and Colorado, and I feel con-
fident that, although future investigations may perhaps modify,
they will not essentially change, the published results.

After examining the Carboniferous limestones as far as Belle-
vue, Nebraska, Mr. Marcou* continued up the Missouri and ex-
amined the sandstones of the Dakota group. In this red sand-
stone he found a rich flora of well preserved leaves of Laurel,
Poplar, Sassafras, Walnut, Oak, Willow, Tulip, a flora which

* ReconDaissance g^ologiqoe au Nebraftka, par Jules Marcou : Eztrait da Bulle-
tin de la Soei6t6 O^logiqpe de France, 2d s^rie. t. zzi, p. Ift2, Jan. 18th, 1864, and
Lea PhylUtea Ordtaoees du Nebraaka. par MM. les Prof. J. Capellini et O. Heer,
tirage a part des M6moirea de la Soei6c6 Helv^tiqae des Sciencea KattnreUea.



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F. V. Rayden on the Cretaceous rocks of the West 175

Pxo£ Heer regards as Miooene, and has more the aspect of up*
per Miocene or even Pliocene than of the lower Tertiary epocn.
Xfievertheless, the flora is not even Tertiary but really lower Gre-
taceous. It is found in a fresh^water formation at the bottom of
the White Chalk of the Missouri Basin. It was Dr. Hayden
who first collected these dicotyledonous plants at Blackbird Hill,
at the Omaha Mission, where a quarry was opened for the pur-
pose of erecting the mission house. Mr. Heer who saw the de-
signs of the first collection made at Blackbird Hill by Dr. Hay-
den, declares that this flora is not Cretaceous, but that on the
contrary it has a very dose analogy with the lower Miocene or
Oligocene of Europe. But notwithstanding these facts, Mr.
Marcou saw superimposed upon the rocks with dicotyledonous
leaves at Pilgrim Hill and on the banks of the Big Sioux, beds
of chalk containing Inoceramus problenuUicus^ Ostrea congesta, &c.,
and that too without any indications of faults or disturbances
of strata. *' I yield to the opinion of Mr. Hayden and regard
these beds as Cretaceous. But I make one reservation; that



Online LibraryJohn AlmonThe American journal of science and arts → online text (page 20 of 102)