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unaltered also. But supposing those projecting masses were
either further upheaved rrora some internal cause, or worn down
and ffround away by the sea or by suba^rial agency and deposi-
ted elsewhere, it seems impossible but that the same effects mast
ensue as we see resulting upon the model from the elevation
and depression of certain screws, and that the axis of rotation of
the crust of the sphere would be changed in consequence of its
having assumed a fresh position on its fluid nucleus, though the
axis of the whole sphere might have retained its original direc*
tion, or have alterea from it only in the slightest degree.

An irregular accumulation of ice at one or both of the poles,
such as supposed by M. Adh^mar, would act in the same manner
as an elevation of the land ; and even assuming that the whole
land had disappeared from above the surface of the sea, yet if
by marine currents the shallower parts of the universal ocean
were deepened and the deeper parts filled up, there would, owing
to the different specific gravity of the transported soil and the
displaced water, be a disturbance in the equilibrium of the crust,
ana a conseouent change in the position of its axis of rotation.

Now if all this be true of a sphere, it will also, subject to cer-
tain modifications, be true of a spheroid so slightly oblate as our
globe.

The main difference in the two cases is, that in a sphere the
crust may assume any position upon the nucleus without any al-
teration m its structure, while in the case of the movement of a
spheroidal crust over a similar spheroidal nucleus, every por-
tion of its internal structure must be more or less disturbea as
the curvature at each point will be slightly altered.

The extent of the resistance to an alteration of position aris-
ing from this cause will depend upon the oblateness of the
spheroid and the thickness and rigiditv of the crust ; while the
tnicker the latter is, the less also will be the proportionate effect
of fiuch elevations, subsidences, and denudations as those with
which we are acquainted. The question of friction upon the
nucleus is also one that would have to be considered, as the
internal matter though fluid might be viscous.

It will of course be borne in mind that the elevations and de-
pressions of the surfitce of the globe are not, on the theory now
under consideration, regarded according to the proportion they
bear to the earth's radius, but according to their relation to the
thickness of the earth's crust; and that, even assuming Mr. Hop-



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Positi&n of the Axi$ of the Earth's crust. 387

kins's eztrame estimate to be trne, yet eleTations or depresmons,
mich as we know to have taken place, of 8,000 or 10,000 feet,
bear an appreciable ratio to the 800 or 1,000 miles which he as-
signs as toe thickness of the earth's cmst

It is, however, to be remarked that the extremely ingenioas
speculations of Mr. Hopkins are based on the phenomena of
precession and nutation, and that if once the po«ibility of a
chance in the position of the axis of rotation of toe earth^ cmst
be aounitted, it is not improbable that the valne of some of the
data npon which the calculations of these morements are found-
ed may be affected.

The supposition of the thickness of the crust being so great
seems also not only entirelv at variance with observM facts as
to the increase of heat on descending beneath the sarfiace of the
earth, but to have been felt by Mr. Hopkins himself to offer
such obstacles to any communication between the surface of the
globe and its interior, that he has had recourse to an hypothesis
of laroe spaces in the crust at no great depth from the surfisu^e,
and filled with easily -fusible materials, in oraer to account for vol*
canic and other phenomena.

But though it may be possible to account for volcanoes upon
such an assumption, yet, as already observed, the phenomena of
elevation and depression, such as we find to have taken place, and
.more especially the existence of vast geological fismlts, cannot
without enormous difficulty be reconciled with such a theory.

Taking the increment of heat as 1"^ Fahrenheit for every 65
or 60 feet* in descent, a temperature of 2400° Fahr. would be
reached at about 26 miles^ sufficient to keep in fusion such rocks
as basalt, greenstone, and porphyry ; and such a thickness ap-
pears much more consistent with the fluctuations in level, and
the internal contortions and fractures of the crust which are
everywhere to be observed. Sir William Armstrong, on the as-
sumption of the temperature of subterranean fusion being 8000.°
Fahr., considers that the thickness of the film which separates
us from the fiery ocean beneath would be about 81 miles.

Even assuming a thickness of 50 miles, so as to make still
greater allowance for the increased difficalty of fusion under
heavy pressure, the thickness of the crust would only form one-
eightieth part of the radius of the earth ; or if we represent the
earth by a globe 18 feet in diameter, the crust would be one
inch in thickness, while the difference between the polar and
equatorial diameters would be half an inch.

In such a case, the elevation or wearing away of continents
such as are at present in existence, rising, as some of them do,
nearly a quarter of a mile on an average above the mean sea-

* Pag«, ' AdTaneed Text-book of Oeolo^/ p. 80.
Am. Joub. ScL—SacoHn Sianw, Vol. XLm, No. 128.— ICabch, IttT.
31



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SM •/. Evans on Oeoiogieal Changes^ 4^.

level, woald cause a great distarbance in the eqailibriam of tiie
crust, si^cient to overcome considerable resistance in its at*
tempts to regain a state of equilibrium bj a movement over its
fluia nucleus.

Whether the thickness of the earth's crust was not in early
geological times less than at present, so as to render it more sus-
ceptible of alterations in position — ^whether the spheroid of the
fluid mineral nucleus corresponds in form with tne spheroid of
water which gives the general contour of the globe— whether or
no there are elevations and depressions upon the nucleus corres-
ponding to some extent with the connguration of the outer
crusty and whether the motion of the crust upon it^ besides effect-
ing climatal changes, might not also lead to some elevations
and depressions of the land, and produce some of the other phe-
nomena mentioned by Sir Henry James, are questions which I
will leave for others to discuss.

My object is simply to call attention to what appears to me
the fact, that if, as there seems reason to suppose, our globe con-
sists of a solid crust of no great thickness resting on a fluid nu-
cleus, either with or without a solid central core, and if this
crust, as there is abundant evidence to prove, is liable to great
disturbances in its equilibrium, then it of necessity follows that
changes take place in the position of the crust with regard to
the nucleus, and an alteration in the position of the axis of ro-.
tation, so far as the surface of the eartn is concerned, ensues.

Without in the slightest degree undervaluing other causes
which may lead to climatal changes, I think that possibly we
may have here a vera causa such as would account for extreme
variations from a tropical to an arctic temperature at the same
spot, in a simpler and more satisfactory manner than any other
hypothesis.

The former existence of cold in what are now warm latitudes
might, and probably did in part, arise from other causes than a
change in the axis of rotation, but no other hypothesis can well
account for the existence of traces of an almost tropical vegetation
within the arctic circle.

Of the former existence of such a vegetation, the evidence,
though strong, is not conclusive. But if the fossil plants of
Melville Island, in fat. 75^ N.,^ which appear to agree generical-
Iv with those from the English coal-measures, really grew upon
the spot where they were now discovered, they seem to afford
conclusive evidence of a change in the position of the pole since
the period at which they grew, as^such vegetation must be con-
sidered impossible in so high a latitude.

The corals and Orthoceratites from Griffiths Island and Com-
wallis Island, and the Liassic Ammonites from Point Wilkie,

• LyoU, ' Frincipkt of Ckology/ 185t, p. 88.



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/. jB. LoughUn on Fht0rescence. SS9

Prince Patrick's Island, tell the same story of the former exist-
ence of something like a subtropical climate at places at present
well within the arctic circle.

To use the words of the Bev. Samuel Haughton,* in describ-
ing the fossils collected by Sir F. L. McClintock, ^' The discov-
ery of SQch fossils in mtu^ in 76"^ N. latitude, is calculated to
throw considerable doubt upon the theories of climate, which
would account for all past changes of temperature by changes
in the relative position of land and water on the earth's surface ;"
and I think that all geologists will agree with this remark, and
feel that if the possibility of a change in the position of the
axis of rotation of the crust of the earth were once admitted,
it would smooth over many difficulties they now encounter.

That some such change is indeed taking place at the present
moment may not unreasonablv be inferred from the observations
of the Astronomer Boyal, who, in his Beport to the Board of
Visit6rs for 1861, makes use of the following language, though
" only for the sake of embodying his description of the observed
facts," as he refers the discrepancies noticed to ^* some peculiaritv

of the instrument The transit circle and collimators still

present those appearances of agreement between themselves and
of change with respect to the stars which seem explicable only
on one of two suppositions — that the ground itself shifts with
respect to the general earth, or that the axis of rotation changes
its position."



Abt. XXVIIL— Om Fluorescence ; by J. Eneu LoughliK,
Philadelphia.

In the year 1845, Sir J. Herschel published two papers in the
* Philosophical Transactions,' on what he termed the epipolio
dispersion of light. His researches were made upon sulphate
of quinia and other organic substances, from which researches
he deduced the conclusion that the colors came from the surface
of the liquid at which the light entered, and that a ray of light
having once passedthrough such a stratum has lost the power of
reproducing the same eflfect. Sir D. Brewster, in 1846, in a
paper read before the Boyal Society of Edinburgh, drew atten-
tion to a similar phenomenon in a solution of the green principle
of leaves, and disproved the ideas of Sir J. Herschel, by show-
ing that the light was dispersed not merely at the surface, but
for a long distance within the fluid. In 1852, the subject was
taken up by Mr. Stokes of Cambridge, and by him ably dis-
cussed. He examined many organic substances and arrived at

* Jonrnal of the Royal Dublin Society, toL i, p. 244.



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S40



/. E. LaughHn on FlMorescenee,



several valuable condusions. He was tbe first to examine the
fluoreseent nature of glass colored by ozyd of nraniam.

In June of the present year, I oommenced a series of experi-
ments upon the tinctures and infusions of the leaves, barks, and
roots of various plants. A beam of sunlight was tbe aeent em-
ployed for illumination. Tbe apparatus, that of Pro£^Stokea
Of the specimens examined, those worthy of note, widx their
results, are given in the following table:



Tinct. of Qoaisia root,

" Veratnim ?iride leaves,

^ Aoontta root,

•* Opium,

^ Belladonna leaves,

** Stramonium leaves,

^ Nuz vomica root,



light green.

greeniBh-yellow.

orange-yellow.

greeuish-yellow.

yellowiah-green.

light green.

yellow.



The tinctures were then deprived of color by being filtered
through animal charcoal, the object being to remove tne colo^
ing matter, as several of them gave reactions which were due to
the presence of chlorophylL On an examination they gave tbe
following results :

Tinct of Quassia,

** Veratrum viride,

Aconite,



Opium,
Belladonna,
Stramonium,
Nuz vomica,



light green,
yellowish -green,
yellowish-green,
deep yellow tint,
yellowish-green,
light green,
light green.



Tinct. of Nux vomica deserves more than passing notice;
when deprived of color it gave a faint green tint in place of tbe
original yellow tint. All the alkaloids of the above that could
be obtained were examined, viz :



Quassia, distinct light green.
Veratria, yellowish-green,
Aconitia, yellowish-green.
Morphia, yellow.
Narcotina, yellow.



Codeia, faint green passing to

orange.
Atropia, yellowish green.
Strychnia, faint green paning to

orange.



The next step was the examination of the fluorescence shown
on tbe pouring of infusions of different substances into water
contained in a tall jar, also the fluorescence shown b^ p&p^
saturated with different infusions. The flame of burning sul*
phur served as the illuminating agent. The intensity of color
'Sraried as is showa in the table.



Infusion of Esculin,
'* Cinchona,

*' Quassia,



Paper,
distinct,
pale,
pale,



laqnid.
disUneL
distinct
distinct



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E. W. m^ardontlu GheimI Drift. S41





Pap«r.


laqmd.


Infiuion of Stramonitim,


pale,
iDCJistioct,


distinct


*" Aoooito,


pale.


•* Veratria,


iodistiDC^


pale.


Galls,


distinct,


distinct



For the light of sulphur was then subatituted that of the fol<
lowing' illuminating agents^ alcohol flame colored by different
fiubetances being u^, with the accompanying results.

Red by nitrate of strontia, no action.

Green by nitrate of baryta, indistinct

Yellow by chlorid of sodium, no action.

Violet by chlorid of potassium, similar to sulphur.

Bed by carbonate of lithia, indistinct

Blue by blue fire, very distinct

Potassium, distinct

Magnesium, no action.

The infusions of the above were spread upon paper and made
to receive the solar spectrum. Those that produced elongation
of the violet portion were —

Infusion of Cinchona, very decided.

^ Esculin, very decided.

*^ Quassia, very distinct

Philsds^l^ Dm. Sth, 1866.



Abt. XXIX. — Note an Dr. Andrews^ paper on ffie OUxcial Drift ;^
by B. W. HiLGARD, Pro£ of Chemistry, University of Missis-
sippi.

Db. Andrews^ interesting paper on the Drift of Illinois, in
the January number of this Journal, defines in a precise manner
a point which I have heretofore failed to find distinctly elucida-
ted, viz.: the exact stratigraphical relations of the great strati-
fied deposits of sand and gravel in the Northwest to such as ex-
hibit unquestionable evidences of glacier action, and not only
those which, so far as their character was concerned, mi^ht
equally as well be referred to that of stranded floes, or shore-ice.
It seemed strange, indeed, that the former should be absent,
where so much of glacial transporting agency was apparent

The oecurrence of glacier-scored rocks is likely, in general, to
be confined to a mcKierate distance from the parent glacier.

Apart from the terminal moraine, we find them frozen into
the bottom or sides of the glacier, and of course into the corres-
ponding surfaces of the iceberg detached from it They are
therefore liberated by thawing long before those unscored an-

* This Jour., Jsn. 1807, p. 16.



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£42 B. SiUiman an Illuminating Oil from California Tar.

gular blocks, which, by falling into crevasses, become enclosed
in the mass of the glacier without penetrating to the bottom.
It is only when two thick glaciers unite into one at a very acute
angle, that scored rocks may become imbedded in the interior
of the combined mass, and afterward be conveyed to considera-
ble distances in an iceberg.

Stratification, therefore, must always be the criterion between
the moraine and the deposits formed of the ballast dropped by
floating ice, though, from the mode of formation, distinct or con-
tinuous stratification could not be expected even in the latter.

Dr. Andrews specially mentions the stratification of the drift
penetrated in the Chicago tunnel, and that by great care it can
DC observed in the greater part of the formation. The latter is
therefore clearly not of the moraine character — it is the result of
the combined action of water and floating ice, as re(juired by
the hypothesis advanced in the paper referred to by him. Nor
does the occurrence of the true " glacial drift " beneath the strat-
ified beds in any way detract from the importance of the latter,
and the necessity of assigning the origin of their 'Hhick masses''
to a cause more powerful in degree and more widely active, than
is implied in the sentence quoted from Dana's Manual.

While angular blocks do occur in the stratified drift of middle
Illinois and Missouri, they, nevertheless, manifestly decrease in
proportion to those of rounded form, as we advance southward;
ana the lithological composition of the " Orange Sand " of the
Southwest is precisely such as we should expect to result from
the modification, in proportion to distance and lower latitude, of
the agencies to whicn the stratified drift of the Northwest seems
to owe its conformation.

IJnhrersliy of Miniwippi, Feb. 2, 1867.



Abt. XXX. — On Naphtha and JtUuminating Oil from Heavy
California Tar {Maltha) ; by B. SiLLlMAN.

Having lately had an opportunity to examine a specimen of
" surface oil," so called, from Santa Barbara county, in Califor-
nia, I present the following experimental results in the hope
that they may not be without interest, as an addition to our
knowledge of one extreme of that class of hydrocarbons which
occur in nature in the fluid form, and of every density, from
those which are but little lighter than water down to the lightest
naphtha found in a natural state.

It is proper to state that the chemical examination of this
sample had chieflv a technical object, to prove whether or not
illuminating oil of good quality could be obtained from the dis-



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A SiUiman on llbtmiruUing Oil from California Tar. 843

tiUaticm of so dense a body. The experinieDts were conducted
on quantities of from five to ten gallons each. The orade oil
was very dark, almost black, transmitting yellow brown light in
thin films. At ordinary temperatures (60^ £".) it is a thick, viscid
liquid, resembling coal tar, but with only a very slight odor.

4ts density at eO"* F. is 0980 or IS"* Baum4 It retains, me-
chanically entangled, a considerable quantity of water, which is
neutral in its reaction. The odor of sulphvdric acid, which is
very decided in this product, as I have noted in its locality, had
entirely disappeared in the specimen under consideration.

The tar froths at the commencement of distillation, from escape
of watery vapor. It yields by a primary distillation no product
having a less density than 0-844, or 87° B. at 62** F.

Distillation to dryness produced in two trials an average re*
suit as follows :

Oil having a density of '890 to 0'900, - - 69*82
Coke, water, and loss, 30*1 8

100*00

la one of these trials the product was divided as follows :

Oil, of density 29* B. at 62* (-886 sp. gr), - 60-0

" " 24-76 ** 63* (-908 •' ), - 17-6

Coke, water, loss, <kc, - - - . * 82'5

100^
The coke is very large in quantity, strong, and is a good fuel,
resembling gas-house coke. The odor of ammonia is given off
toward the close of the distillation.

It is well known to distillers of petroleum that by the process
called " cracking," heavy oils unfit for illumination are oroken
up into bodies of less density, from light naphtha to the heavier
illuminating and lubricating oils. This process is simply the
application of a carefully regulated heat producing a slow distil-
lation. By this treatment the molecules apparentlv rearrange
themselves into groups of different density, which by a subse^
quent distillation are divided into fractions (or '* heaps" as Mr* -
warren calls them) of tolerably constant boiling points.

The first distillate, having a density of about '890 at 60'' F.,
treated in this manner, yielded a product having a density of
about -886 at 60®, or only 1^ Baum^ lower than before dietilla^
tion. AfWr treatment with sulphuric acid and soda and redis-
tilling from soda, it had a density of -880 at 60° F. Upon re-
distilling, 100 measures of this last distillate yielded —

Light oil having a density of about *834 at 60^ F., 21*58

Heavy " " « u .qqo " 66** F., 87-41

" ** " « ii .916 « 64^ F., 84'68

Coke, Ac, 6*48

■* -

10000

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844 B. SilHman on Bhminating OUfrom California Tar.

In another experiment andertaken with a view to "cracking,"
&c., treating ana redistilling with soda, the products were as al-
lows, stated in percentages of the whole quantity operated oo,
the several steps being as before.



Naphtha,* «p. gr. about •760 at 60* F.,
Oil,t " " -886 « «

♦* 44 tt .393 tt 44

« 44 44 .921^

LOM, -



11-S3

66-23

12-67

8-56

6-22

100-00

The illaminatin^ oil from both these experiments, after treat-
ment with sulphunc acid and soda in the nsnal manner, acquired
an agreeable odor, a light straw^yellow color, and burned as
well in a lamp as good commercial oil.

With a view to test the effect of heat aided by pressure in
breaking up the heayy hydrocarbons — a method of treating
heavy hydrocarbon oils patented in 1866 by Mr. James Young
of Glasgow — ^a portion of the first distillate from the crude ou
was suqected auring distillation to a pressure of ten to fifteen
pounds to the square inch, in an apparatus adapted to the pu^
pose, the distillate thus obtained b^mg about the same density
as in the first named experiment, *890 at 60"^ F.

From this distillate were obtained, after the ordinary treat-
ment with sulphuric acid and soda, the following products:

Light oil, sp. gr. -825 at 60^ F., - - 19-2 p. o.
Heavy ** «* -886 « " - - 26-86 »*

44 44 u .913 44 44 . . 33.14 a

Coke, loss, Ac, - - ^ • - 16-80 "

10000

The illuminating oil from the last experiment flashed at 80^ F.
and lighted on the surface at 85^ F., showing the presence of
naphtha or some very light body, the quantit;^ of which cannot
be very considerable. The light oil could with care be taken
off in practice without materially diminishing the yield of illu-
minating oil. It would be rash to conclude that there may not
be an important economical advantage in employing in the large
way Mr. Young's method of treatment under pressure, over that
of *' cracking" by a regulated heat alone. It is highly probable
that there would be found an important saving of time, as under
a regulated pressure and a corresponding increase of tempera-
ture, the transformation of the heavy oils into a mixture of
those of less density, will occur more speedily. The experi-
ments herein mentioned gave nearly the same result whether,

* This naphtha caught fire from a match at ao atmotpheric temperature of 66® F.
t This oil flashed at llS® F. aod ignited at 124^ F.



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B. Silliman on lUumituUing Oil from California Tar. M5

{>re8Btir8 was uaed or not; a certain loss, all fUling npon the
ighter portions^ was found to result from leakage of the appa*
ratus under pressure, which in the larger way of operating com*
mercially could be avoided.

No paraffine could be detected by refrigerating the heavy oils
obtained in these distillations in a mixture of salt and ice. It
is no doubt the absence of this body from the series of products
obtained from the California oils generally, that accounts for the
illuminating oil burning well at a density Considerably below
the commercial standard for oil obtained from Pennsylvania pe-
troleum — a difference enhanced also by the absence of any con-
siderable quantity of light naphtha. The lubricating oils of
this series, likewise free from paraffine, retain on this account
their fluidity at low temperatures.

The light oils obtained in this series of experiments corres*
pond respectively to 12*96, 14*56 and 18*96 per centum of the
crude oil. The total commercial products are about 60 per cent
of the crude body, which likewise yields sufficient coke to supply
the fuel required in the distillations.

In the large way, by returning the lightest oils to the heav*
ier portions in the successive distillations and employing Mr.
Young's method by pressure, it is probable the product of light
or illuminating oils may be raised in these very heavy natural



Online LibraryJohn AlmonThe American journal of science and arts → online text (page 28 of 102)