John Almon.

The American journal of science and arts online

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20-6 -8769

21-5 -8989

19-6 -8561

21-2 -8879

20-1 -8660

21-6 -8989

19-4 -8521



1547
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Rbao- Com- Tan- Int Mean ▼aloes of



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20-9 -8819



int resist



19-4 -8621 ^^ 25-46
87-29

20-7 -8779 ....

21-84
19-1 -8462 -— - 25-52
29-21

20-8 -8699 ....
24-90
18-9 -8424 ^^ 2402

20-4 -8720 ....



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18-6 '8866

20-2 -8680

18-2 -8287

20-8 -8699

18-2 -8287



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81-91

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Tabls YI (oontiiiM 1).



Mean valoM of
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40-821

1 86-6
82*68 J



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Rheo- Com- Tan- Int Menn values of



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26-10 I

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19-8<» -8600 ....

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86-00
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82-30 I

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82-30

19-7 -8581 ....

26-75
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2 0*49



80-69
16-6 -2962 ^' 8018
29-67



19-6® -8641

6

19-6 -8661

6

19-4 -8521



80-84
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19<» '8448 ....

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86-98




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28-86

19-4 -8621 ....

15-8 -2880 ??1? 82-76.

82'76
19-4 -8521 ....



88-44



15-6<> -2792
18-8 -8405
16 -2679
19 -8448
15-8 -2786
18*6 -3865



8064
26-48

29V6
28-06

80-96
84-79



88-54



28-66



82-87 J



81-69




10


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18-60 -8866

2930
19 -8448

82-0
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320



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82-0
83-64



80-781

181-86
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82-77




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14-6 -2605

19 •3448

14-6 -2686

18-6 -8865



82-66
8109

80Y7
88-19



81-821



h81-76



81-681



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20 12-1 -2145 |51^ 86-97
86-78

18-8 -8808 ....

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18-2 -8287 ....

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86-27




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and Resistance of a Gmlvanic Circuit



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Tablb YI (contiiiMd).



Mheo- 0dm- t^o- lot Mean Tftloct of
cted ptm. gBBL nsisL lot ntiaUnce.

18<» -8249 ....

86*69
80 10 -1768 ^^ 84-91

18*8 '8808 .... ^87-88

80 108 1817 ^t ^^''^

18-1 -8908 ....

80 10^1 1781 ^~ 86-71
86-48



Rbeo> Com- TMi- lot lf««B«alnMor

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18*9« -8987 ....

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177 '8191 ....
86 89

90 1797 jj^j 84-98J

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80


80





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40


40


40


40





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8-7 -1620

17-8 '8911

84 1477

17-7 -8191

86 -1618

17*4 -8184

88 -1469

17*8 -8116



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86-96

84 07
8417

88*96
87 88

8484
86-94



86-181
84*97
87-16
86*04



84-7«



86-09



44-64

44*64



60 7*40 1899

17*8 -8116

60 6-9 1210

0* 164 -2948

60 70 1928

168 -2926

6*8 -1192

168 -9926 ....

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8811

4849

41 '27
41-27



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kl*87



88*26



8811]



48*19



41*97



88-98



89*78




120


120


120


200


200


200



18-8* -9996
48 -0769

16*4 -9948
4-4 -0770

18-6 -9982
4n -0769

16-6® -9799
9-8 D489

16*8 -9880
9-8 -0489

16-6 -9799
9-7 D479



lis -i



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42T6 '"^

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49-29



41-86




120

16
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8V-47

41 78

42-47

. . • •
4069

4148



40*97



49-19



y 41*64



4108



89*69
4*1 -0716 ?l|{ 89*77
8996
•2867 ....



88-69
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40*08
166 -9792 ....



89-67



16-80 -2880 ....

200 2*7 -0472 ^— 40-861
4189
16*8 -2786

200 26 -0464 *^I' 89*89
88-84
16 6 '2792 ....



40H)9



* TUt obterratioo was tnftde ifter the buttery having been open for tome time.
Ail Joom. acx.-4BcoicD 8brixs, Vol. Zim, No. 197.— Jjjc, 1807.
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Ax. Jwm. Sox.— 8icioin> Suixi , Vol. XLm, No. Id7.— Jur., 1107.

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/. Ife Smith &n Colorado Meteorites.



Art. VIII. — On Gohrado Meteorites — Russel Quick Meteoric Iron^
and Bear Creek Meteoric Iron; by Prof. J. Lawrence Smith,
Loaisville^ Kj.

The first of these irons I described in the September number
of this Journal, calling it the " Colorado meteorite.'' Owing to
the discovery of another in the same territory (specimens of
which have been in my possession for some little time), it will be
proper to designate the first mass as the "Bussel Gulch" iron
and the other as the *' Bear Creek" iron. Of this last there are
two short notiises in the November number of this Journal, pages
260 and 286, the specimen of it in my possession has enabled
me to make a thorough examination of the constituent& The
piece I have has a portion of the exterior attached.

As has already been stated by Prof. Shepard, it is coarsely
crystalline, and laminated from the effects ot decomposition be-
tween the crystals ; the surface contains considerable pyrites, al-
though Prof. Shepard did not discover any in his specimen. I
was enabled to separate and analyze magnetic pyrites, schreiber-
site and nickeliferous iron. Of the magnetic pyrites suflGicient
was separated to make a quantitative determination which was
as follows :

Sulphur, 35*08

Iron, 61-82

Nickel, -41

In&olubU residue, 1*81

9912

The schreibersite was not obtained in sufficient quantity for
a complete analysis; about 60 milligrams of the pure mineral
gave alHhe constituents usually found in this interesting mineral.

The nickeliferous iron, constituting of course the great bulk of
of the mass, was composed as follows :

Iron, 83*89

Nickel, 1406

Cobalt, -83

Copper, .... minute quantity
Phosphorus, - '21

98-99

The laminae of iron are often very brilliant, having the luster
of silver and caused me to suspect more nickel than was found.
It was supposed that in the decomposition of the crystals the
iron would disappear more rapidly than the nickel, and that by
a process of cementation, the nickel would accumulate in the



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/. If. Smith vnnew localiUes of Minerals, etc. 07

laminao ; but &om-«arefal examination of the pToeess of deoom-
positioD, there is no doubt that the interior of the mass will not
differ materially in its composition from the analysis already
given of the nickeliferous iron. Besides the minerals already
mentioned, and which properly belong to the original mass, there
is much oxyd of iron, containing some nickel arising £rom the
decomposition of ike sur&ce.



Abt. IX. — On a new locality of Tetrahedriie, TennantiUj and Na^
criie^ with some account of Oit Kellogg Mines of Arkansas; by
Prof. J. Lawbence Smith.

A SHORT time since Prof. E. T. Oox of Indiana sent to me an
antimonial copper ore containing silver, one fragment being the
termination of a crystal having a number of small but beautiful
faces, another was a minute crystal of a different form ; in the
hands of Prof. Cox a blowpipe analysis had given about five
per cent of silver in some of tne mineral.

The crystalline fragments were first examined and they enabled
me clearly to trace out tetrahedrite in one and tennantite in
the other. The faces on the tetrahedrite were small but beauti-
ful and very numerous ; from the number on the fragment ex-
amined there would not have been less than from 60 to 70 had
the crystal been perfect : it corresponds very nearly to the cy ratal
figured in Dufrenoy's Mineralogy, plate 124, fig. 441, which he
speaks of as coming from Moschellandsberg, a locality that I am
not able to discover. Good measurements were made on a few
of the faces.

P on P 70** ; P on ft» Ih^"" 30' ; P on a* 144* 30'

Specific gravity of different specimens varied from 4*78 to
6*08 ; the latter was the sp. grav. of the above crystal. The
ansdysis of two specimens, No. 2 being a part of the crystal,
gave





1.


2.


Antimony,


26-60


. 2701


Sulphur,


26-71


2532


Copper, -


86-40


33-20


Iron,


1-89


'82


Zinc,


4-20


6.10


Silver, -


2-30


4-97


Arsenic, -


1-02


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9902 98*03

The quantity of No. 2 analyzed did not exceed 800 milli-
grams.



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68 /. L. Smith on new localities of Minerals, etc.

There are two minerals consisting of minnte micaceons scales
on the quartz containing this gray copper. One of them I could
not obtain in sufficient quantity for examination; from an im-
perfect examination I conclude that it is muscovite; the other
mineral, a soft unctuous talc-like mineral, is nacrite, composed
as follows :

Silica, 66-02

Alumina, - - - - - - 26*11

Oxjd of iron, 2*20

Manganese, trace

Potash and soda, - - - - 1*18

Water, 4 98

09-49

These minerals came from a'n exceedingly interesting mine
in Arkansas that is an yet almost unexplorea; I have obtained
a full description of it from Prof. Cox and I think it would be
well to give it here, for besides being likely to prove of consid-
erable commercial value when properly explored, there will
doubtless be found many interesting mineral species there.

The Kellogg mines are situated 10 miles north of the city of
Little Rock in Pulaski Co , Ark. The country in the vicinity is
rolling, the highest hills are about 270 feet above the water level
of the neighboring streams. The surface rocks are thick and
thin beds of sandstone alternating with shales occupying the
base of the coal measures. The rocks are but little disturbed
and are for the most part horizontal. There are no metsmor-
phic rocks showing themselves at the surface nearer than Little
Bock on the south side of the Arkansas river. Innumerable
veins of milky quartz are seen traversing the sandstones and
shales.

About seventeen years ago lead ore was discovered at these
mines by Mr. Kellogg, companies were organized and mining
operations carried on extensively for about one year, when the
flattering accounts of the gold discoveries in California caused
the miners to leave, and the work which had been badly con-
ducted was abandoned. Many tons of the ore which is an ar-
gentiferous galena (containing 60 to 200 ounces of silver to the
ton) were extracted from the mine and finally the greater part
was shipped to England and sold at a good price. A smelting
furnace has been erected on the groumla, but for lack of skill,
the proprietor never succeeded in working the ore profitably,
consequently the impression was produced that the ore could
not be smelted, but tnere is no good reason for such an opinion.

Since the mines have been abandoned, the old shafls, ranging
in depth from fifteen to seventy feet, are all filled in, and the
country has become covered with a dense undergrowth of brush



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H. Mitchell on recent Soundings in the Oulf Stream. 69

and briars. About one year ago Prof. Cox revisited these mines
for a company who had in view to lease or purchase them ; it
was during ihis visit that the gray copper above referred to was
discovered. This ore has previously esaiped tlie observation of
others who had explored these mines. It is impossible at pres-
ent to see the ore in place, and those who previously woiked
the mine give conflicting statements as to the manner in which
the ore is found.

The vein-rock and associated minerals with the galena are
white quartz, spathic iron, zinc blende, copper pyrites, gray cop-
per, tennantite and nacrite.

The mines are now in the hands of a new company, and the
latest information from their operations are, that matters look
well; the vein now being worked is nearly three feet wide,

Principally lead ore, the balance being zinc blende; twenty
ands are at work, and the shaft is down forty-five feet My
opinion is, that in time this mine will become of considerable
importance, and lead to furtlier developments of argentiferous
galena in that region.



Art. X. — On recent Soundings in the Gulf Stream. — Abstract
of a paper read before the National Academy of Sciences;
by Henky Mitchell, Assistant U. S. Coast Survey.

Early in the spring of the present year an application was
made to tlie CoastSurvey by the International Ocean Telegraph
Company for information relative to the form and character of
the bottom of the Straits of Florida between Key West and
Havana along the proposed track of the submarine telegraph
cable which is to connect the United States wiih the West India
Islands. It was clearly the province of the Coast Survey to
supply information of this sort, and a special survey was there*
fore ordered under instructions from Mr. J. E. Hilgard who, dur-
ing the illness of Prof. Bache, conducts the work of this bureau.
These instructions were carried out carefully and under favoring
circumstances, so that the results are entitled to confidence.

The distance from Sand Key, on the extreme southern point
of the Fh^rida reef to El Moro rock at the entrance to Havana,
is but a trifle over 82 miles. To lay a cable over this short dis*
tance would seem to be an easv task and one that should long
since have been executed. In tact, however, the locality offtsrs
a new problem to the engineer, viz: to lay a cable nearly at right
angles to a stroitg stream, or system of streams^ fli)whig through a
rofky pass of great depth. The new survey, if it does not, as is
hoped, supply the elements for the solution of this problem, at



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70 H. Mitchell on recent soundings in the Gulf Stream.

least develops and gauges the di£5culties of the task, and inci*'
dentjilly adUs a few items of interest to physical inquiry.

The line of maximum depression was struck at a point 24
Tiiilrs north of the Moro, and followed some distance to the north-
east vvitli dr})ths or 853, 846 and 794 fathoms. The direction
ot this line does not correspond to that of the Gulf Stream in
this neighborhood ; but a glance at the map will show. that a
S.W. course would be a natural one for the Polar Current, as
it is called, which runs near the bottom.

The numerous soundings of this survey make it possible to
develop a profile of section from Sand Key to the Moro, and the
subjoined table gives the numerical data for such a profile.

Section of Soundings across the Straits of Florida^ from Sand Key

to El Moro,



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5-0


Remarks.


£^


Key.


Moro.
79i


CHtor.


of line.


ii




, A


2*




66




rock.


Coral strewn orer with shells.


5 B7ito8i


•?4J


Ill


126


6


u


Specimen of coral debris obtained.


^


U


714


129


182


1


«




8.D


14i


67*


2h9


809


2


u


Specimen of coral debris.


S|E


18i


64


869


897


1


mud.


Specimen of gray mud.
Specimen of mud nearly white.


!|F


24i


68


482


466


1


41


g^G


29i


68i


604


663


2


l(


Specimen nearly white with dashes
















of red.


84


48i


687


!^


1 '


It


Specimen of stiff mud, nearly white.


38


44*


794


is


1


It


Specimen gray and granular mud.


, i


46i


86*


846




1


II


Specimen nearly white with red










o °

If






tinge.


i ••


61i


81


842


8


U


Specimen same as above.


1- g


66*


26i


818


si


2


it


Specimen same as above.


Is f,


«0


22*


466


?s


2


U


Specimen of mud with drab color.
No specimen — some doubt of cast.


:i«


6H


20*


880


Sti




U


e» d


67i


16


710


£




hard.




1 c


1H


9


748






mud.




S i


78i


8*


688


620




sand.


Sand or mud of reddish brown hue.


80i


1*


248


244




rock.


A small shell obtained.



In this profile, which is, strictly speaking, that of a diagonal
section, the point of maximum depression is found 87 miles
from the Moro, and is 848 fathoms. The approaches to the great
valley from the two coasts are dissimilar in general features.
From the northward the bottom falls away in terraces whose in-
tervening slopes are nowhere abrupt; while from the southward
an irregular and hilly approach is found with indications of ab-
rupt if not precipitous changes of elevation. Above the terra-
ces of the north shore the sea lies almost motionless, while
among the ca&ons of the southern half of tbe Straits flow the
Gulf Stream and its counter currents.



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iBL. Mitchell on recent soundings in the Gulf Stream. 71

*rheae natural distinctions authorisse ns in taking up separately
the descriptions of these approaches, and we shall proceed to do
so briefly, commencing at Sand Key and following the profile
southward from A to I: then commencing at the Moro and fol^
lowing northward from a to t (see table).

Northern Approach. — Leaving Sand Key, the water deepens
rapidly to 13 fathoms, then shoals again to 7 fathoms upon a
coast bar or ridge parallel to the reef, and scarcely fths of a mile
distant from it. Seen from the deck of a ship upon a fine day
this bar is marked by a narrow belt of pale blue-green water in
beautiful contrast with the dark blue-black of the ocean. The
bottom can be seen on crossing it and appears to be a pure white
rock tn situ, strewn sparsely over with fragments of the weathered
and brown reef rock. Two miles farther out carries us to the
point A, where our table for the profile commences with sixty
five fathoms of water on a slope of one foot in thirty seven.
The next points B and lie upon a nearly level plain which
terminates about twelve miles from the reef in a slope of one
foot to twenty-two. Upon this terrace numerous soundings
were made covering about eight miles of longitude, which show
that the formation belongs to the reef system and lies parallel
to it. Chips of white coral rock were brought up in one of the
casts — in all of them the hard bottom was felt by the hand.
At what appears to be the foot of the fore slope of this terrace
(point E) the bottom is found to be soft muq, and a specimen
procured proved to be of a grey color quite in contrast both as
regards color and consistency, with that obtained above or be-
yond. It differed from the white muds beyond, of which we
shall hereafter speak, in possessing a granular character and re-
taining the same when dry. It is conceived that this terrace
was once a dry reef covered over like Sand Key with dark
fragments of agglomerated reef rock, and that a subsequent
sabmergence has caused all this loose and weathered material to
be swept down to the foot of the fore slope.

Between D and E, in about 800 fathoms, the swept portion of
the Florida Beef, if not also the base of the formation, is passed.
At F, G and H the bottom is of nearly white mud, with dashes
of red at the last named point. These muds were found to set
on drying. The mud with dashes of red is supposed to be the
debris of a kind of coral, quite conimon upon tne reef, which is



Online LibraryJohn AlmonThe American journal of science and arts → online text (page 8 of 102)