John Almon.

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sulting from the transverse walls raised in the tube during the vibration.
The experiment is so easily repeated (blowing by means of a bellows or
even the mouth) and the nodal figures so exoeeding beautiful both dur-
ing and after the intonation, and the same may so easily be preserved
thereafter, that every reader ought to repeat the experiment. Measuring
the distance of any two nodal areas fives with great accuracy the hal^
wave-length of the tone; the same pipe may in quick succession — after



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CkemiMiry and Physics. 2SIS

nwraly thakiog up the silica id the pipe — be made to give different tones,
the piteh of which is easily ascertained by the ear, and the length of
whose waves is found to coincide admirably with the calculation based
npon the first determination and the interval — or the velocity of sound
and the number of vibrations. The known methods of Hopkins, Ednig,
and others, for representing the vibrations of the air in organ pipes are
very deficient: Kundt's method is as complete as it is simple.

Bnt it shows more than anticipated. If repeated by means of a verti-
cal pipe, with a ffcu-Jlame in place of the silica, this fiame shows a cor*
responding stratification in dark and bright layers — the luminous strata
evidently due to an accumulation of carbon particles. The mutual dis-
tance of these luminous strata is nearly proportional to the length of the
tube. From this and other facts Dr. Kundt concludes that the rippling
of the silica and the stratification of the flame probably are due to the
higher or secondary tones (obert&ne of Helmholtz) coexisting with the
one produced, and whose wave-length is measured by twice the distance
between two consecutive nodal areas.

For farther detail, and many other interesting results, we must refer to
the paper of Eundt in Poggendorff*s Annalen, 1866, cxxviii, 337-^55
and 496. In the same volume, page 610-618, the same investigator
gives an interesting method for the observation of the vibratory forms of
plates by means of reflection. o. h.

12. Influence of the interior friction of the air on the transmission of
sound ; Stsvan (Acad. Vienna, April, 1866). — The analytical results are :

(1.) The velocity is greater for the tones of* higher pitch ; for the
h^hest tones it only is one-thousandth of a millimeter [so that disper-
sion of sound is practically impossible ?].

(2.) The amplitudes of plane progressive waves decrease in a geomet-
rical progression, the ratio of which is proportional to the square of the
number pf vibrations. The amplitude is reduced to one-ninth in 1000
naeters for 10,000 vibrations, or in 100 meters for 30,000 vibrations per
second.

(3.) In stable vibrations the wave-length cannot be greater than four
tiroes the mean excursion of a molecule of the air (as assumed in Ero-
nig^s theory of the construction of gases).

(4.) The amplitudes in stable waves decrease in geometrical progres-
sion of the time, the ratio being proportional to the square of the num-
ber of vibrations. Thus the amplitudes of tones of 1000, 10,000, and
30,000 vibrations will in 100, 1, and ^ second be reduced to one-half
their original amount — Vlnstitut^ 1866, p. 271. o. h.

13. Interferential tones, — In May, 1866, Stefan communicated to the
Academy of Vienna some interesting experiments, giving for tones, the
vibratory motion of which cannot be contested, a transformation per-
fectly analogous to the theoretical decomposition of light-waves travers-
ing a quartz crystal in the direction of the axes and producing the rota-
tion of the plane of polarization.

A square plate exhibiting two nodal lines at right angles will produce
a more intense tone if the two opposite sectors Hiaving the same motion)
are covered with a card of their own figure and size : for then the parta
Am. Jouk. 8ci.— Sbcoitp Saaias, Toi*. XXJII, No. ISa— Mabob, 1867.
33



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of the plate adjaeent to these will alone move the air with ooneordaiit
impulses. If now the card (or the plate) be rotated n' times a second,
the intensity will show n' periods per second ; if the amplitude of the
original vibration of the plate be a, the amplitude corresponding to the
rotation of the card be a , and the pitch of the tone of the plate n, we
have a-^a' &in 2n*nt, and hence the original tone A=asin2n9r< becomes

a' a

A=a'6in in'ntsm 2nnt=z-^ coi2{n^nf)nt'^-coB2{fi^n*)ntj
2 2

that is two tones of pitch n— »' and n'\'n* (or a graver and a higher tone)
will be heard instead of the primary tone of pitch n.

Thus Stefan found that a plate giving the tone Jis^^ which according
to Quincke's table (this Journal, Nov. 1866, p. 417) corresponds to
185=n vibrations, produces, when n':=10 rotations per second, the tones
/2=:l74'6 and ^2=196, which are verj nearly 185d=10. Ulnstitut
gives jis^^ etc., no doubt by a mistake in translating Stefan's German
notation. — V Institute 1866, No. 1710, p. 327 ; Cosmos^ 1866, vol. iv, pp.
468, 450. o. H.

14. FoueaulVs silvered ohjeetives for observations of the sun. — A very
ingenious method for close observation of the solar disc wa^ communi-
cated by Foucault in September, 1866. Having noticed that no heat
and very little light is transmitted through the thin bright silvering of
his glasses, he coated the outer surface of the objective of a refracting
tele8cop>e with such silvering, and found, as he expected, that all heat-
rays were reflected, as also the greater part of the light, so as to permit
only a pale bluish-violet to pass through. LeVerrier reported, October,
1866, most favorably as to the results obtained by a 9-inch refractor
(equatorial). No heat could be felt in the very focus of the objective
directed toward the sun — thus freeing all solar observations of a very
great cause of error. Furthermore only the ultra-red rays are really ab-
sorbed ; all others are, as the prismatic spectrum shows, only diminished
in intensity so as to give a steady (calme) and pure image of the sun,
showing all detail of outline and color with excellent definition, and per-
mitting a magnifying power of 800. — Vlnstitut^ 1866, pp. 281, 318;
Cosmos, 1866, iv, 387, 430. o. h.

15. Lead-thallium glass has greater density and refracting power than
common lead-flint glass; 300 pure sand, 200 minium, and 335 carbon-
ate of thallium (instead of the usual 100 carbonate oif potassa), give a
glass of density 4-235, index of refraction l'7l, and only very slight yel-
lowish tint It has been made in England. — L'lnstitut^ 1866, p. 320.

O. B.

16. Expansion of water and mercury ; A. Mattuibsssn. — ^The results
of this very elaborate investigation are — the volume of water at any
temperature 1? C. is V=:a— 6<+c<*-rf/3, the volume at 4* C. being 1
and the coefficients



for 4°<*<82
100018845828
0000006798ee
0-00000752824
000000007178



for 82<<<><100^

0*999696

0-000000

0-0000054724

0-000000011260



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Chemuiry and Physics.



255



The coefficient of expansion for a volume of mercury he finds from
^ve series of determinations (per degree C.)

0-0001812
Regnault found 0*0001815.
— Poggendorff'^s Annalen^ 1866, cxxviii, 512-540. o. h.

17. On the expansion of crystals, — Fizbau has invented a method for
the exact determination of the coefficient of expansion of small solids
fonly a few millimeters thick), and obtained important results thereby
(Cosmos, 1865, xxvi, 641). The following is the substance of a later and
more elaborate research of Fizeau.

Let the coefficient of expansion in the direction of the three axes of
elasticity of any crystal be represented by a, a', a"^ then the expansion
D iD'any direction determined by the three angles ^, d', d"^ will be

D=o cos^ ^+a' cos* ^'+a" cos^ d"^

and the cubical expansion is

which is the same as D for ^=^'=z^"=54^ 41', or in a direction at
light angles to the surface of a regular octahedron whose axes coincide
with the directions of o, a', «".

Fizeau determines a for three temperatures (viz., 20^, 40^ and 60^ C.)
from which he deduces the value for a at any temperature ^, and also

the variation of a for each degree, that is —^^ which is a constant

quantity.

He puts the crystal with one side on a platinum support, and places a
polished glass plate above the upper surface so as. to leave a small inter-
val ; by means of a telescope he counts the number of fringes passing
beyond certain fixed points of the support, these Newtonian rings being
produced by an alcohol flame with salt, and changed by heating the
whole apparatus. For the detail of this method we must refer to the
original paper — we can here only give a tabular view of the results ob-
tained thereby. At 40^ G. the coefficient of linear expansion in the
direction of the axis is a, at right angles to the same o', cubical expan-
sion c=a-|-2a', A the variation for each degree; / is the temperature at
which the body has a maximum of density. The unit of a, a', o and A
is 0*00000001, or one hundred millionth of the unit of length or volume.

__



Platinum with 01 iridium, 888*847

Mirror-glaat,

Diamood,

Coprite,

Beryl, 106

Quarts, 781

Rutile, 919

Cassiteritc 892

Periclase (artificial),

Spartalite (ZnO), 816

Corundum, 619

Hematite, 829



A


o'


A


c


A


0-7688


• ■ . •


• • ■ ■


• • • •


. . • •




• • • •


• . . •


2881


4-74




• • • •


• ■ • •


854


4'82


• • • •




• ■ • •


279


6-30


114


187


1-88


880


8-80


1-77


1419


2-88


8619


6-68


2-26


714


110


2374


4-46


1-19


821


076


1034
8129


2-71
801


1-86


589


1-28


1894


4-82


2*05


688


2-26


1705


6'66


1-19


886


2-62


2601


6-48



-42«-8

- 40'8

- 4«-2



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Senamiontite,

ArseoioiiB acid (artificial)

Spinel (regular system, hence a=:a's=a"), .

1. Rabj from Ceylon, •

2. Pleonast from Warwick,

S. Oabnite from Fahlnn,

4. Kreittonite from Siiberberg



e


A


f>C.


6889
12378


1-71
2087




1787
1806
1766
1760


r2«

6-84
6-19
6*81





It M evident that t is found bj e— A<=0; it thus appears that the
maximum of density instead of being an exception roaj be the rule !
Fizeau has cut a needle of beryl wherewith he proposes to verify it —
Poggendorff'^s Annalen^ 1866, cxxviii, 564-589. o. H.

18. Expansion of a conductor due to the galvanic current ; by Er.
EoLUND (Swedish Academy, January, 1866). — When a current passes
through a conductor, the latter is heated to a certain temperature, ^,
al:K)ve its surroundings and consequently expanded ; but it may be ques-
tioned whether this expansion is due to the temperature of the conductor,
or whether it is greater, so that the galvanic current itself produces a pe-
culiar expansion of the conductor through which it flows. That this
last is the case ha^t been experimentally demonstrated by Ediund. This
expansion might perhaps be called galvanic ; the usual, caloric expansion.

He very carefully measured the actual expansion, £, of the conductor
(platinum, iron and brass were used) and the corresponding resistance R.
Next he determined the expansion produced by heat alone in the same
wire, so that he accurately can determine the temperature, Tj, of the con-
ductor from E, considering this expansion due to the temperature alone.
Finally, he carefully determines the influence of temperature on the con-
ducting power of the very same wire; so that he can calculate the tem-
perature T^, which would correspond to the above resistance R — that is,
he determines the actual temperature of the conductor while the current
circulates by the resistance it offers.

Ediund found T^ invariably from 1° to 10** lower than T, — or the ac-
tual expansion, E, of the conductor is greater than would be produced
by the actual heating, T^, of the same, this being calculated from the
measured resistance, R, of the same conductor. The expansion was not
due to a change in elasticity, for the tension of the wire varying from
2^ to 3^ pounds did not change the result. This galvanic expansion in-
creases rapidly with the intensity of the current-^\>\xt according to what
law is still unknown. — Poggendorff^s Annalen, 1866, cxxix, 16-44,

O. H.

II. MINERALOGY AND GEOLOGY,

1 . Note on the use of the name JTudson-river group : by F. B. Mkek.
— In the Introduction to the Illinois Paleontology, just published, Mr.
Worthen and the writer have some remarks on the impropriety of trans-
ferring the name Hudson-river group, from the older series of contorted
slates and argillaceous sandstones to which it was originally applied (ex-
isting in great force along that stream above the Highlands), to the more
modem group composed of the Lorraine shaleSy I^rankfort slates^ hc^
with which the true Hudson-river rocks were subsequently confounded.

Since these remarks were in print, I observe we were in error in sap-



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Mineralogy and Otology. 267

posing that late investigations had brought to light facts casting doubt
upon the occurrence of the later types of fossils along any part of the
liudson river, in other than the little isolated masses alluded to as occu-
pying synclinal axes in the older rocks, or entangled amongst their con-
torted strata. The fact, however, that the more modern types of fossils
are not known to occur under other circumstances than those mentioned,
along the part of that stream regarded as the typical localities of the
Hudson-river group and lying mainly between the Highlands and the
region of Albany, while the name, as originally used by Conrad and
Mather, was expressly applied by them to this older series, which they
regarded as belonging to the Cambrian of Sedgwick, is believed to be a
sufficient reason for objectiDg to the transfer of the name to the later
group. Hence if retained at all, it is believed this name should be ap-
plied exclusively to the group of rocks for which it was originally in-
tended, and to which it must always carry the mitds of those who may
look into its origin and history. As it, however, subsequently became
very generally also associated with the more recent series already alluded
to, it probably could not now be restricted without much inconvenience,
to the rocks to which it- properly belongs. Consequently the surest, if
not the only, way to avoid confusion, will be to strike it entirely from our
nomenclature. The name applied to the more recent rocks, in Mr.
Worthen's Report on Illinois, is the Cincinnati group, from the great
development and highly fossiliferous character of these beds at the well-
known city of that name in Ohio.*

2. Note on Bellinurus Banof^from the Illinois Coal-measures; by
F. B. Meek. — In the Proceedings of the Academy of Natural Sciences
of Philadelphia for March, 1865, and again in the Illinois Paleontologi-
cal Report, Mr. Wortben and the writer have described a new species of
crustacean under the name Bellinurus Danes, In both of these publica-
tions it is stated that we had not seen the original description published
by the founder of the genus BellinuruSj nor a full description of it by
any other author ; but that our species, although closely allied to the
forms figured by Prestwich and usually referred to this genus, differs from
the characters assigned it by Portlock, Owen and some others, in having
its body segments anchylosed, as well as in the position of the eyes.

In the Quarterly Journal of the Geological Society of London, Nov.
1865, p. 490, 1 observe Mr. Henry Woodward, in speaking of the genus
Bellinurus, says, '^ the segments of the abdomen, if not anchylosed in all,
are so in most *' of the species.

In ^ The Readier -' of Dec 1 866, containing an abstract of the Proceed-
ings of the London Geological Society, it is stated that in a paper read
by Mr. H. Woodward, Nov. 1866, "On some points in the structure of
the Xiphosura^ he remarked that this group is *' divisible into three

Sinera ; 1st. Bellinurus, having 5 freely articulated thoracic segmenta,
ree .anchylosed abdominal ones, and a telson ; 2nd. Prestvnchia, a new

* It has been suggested that Prof. Safford's name, Nashville group, should be
retained for this formation. To this I d* not seriously object : the only reason for
not using it is, that Prof. S. applied it to a group including along wilii the so-called
Hudson river rocks, the upper part of the Trenton. Hence it cannot be conveo-
iently used when we wisn to speak with precision of the later so-called Hudaoa
river rocks, as a distinct formation from the Trenton.



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genus, having the thoracic and abdominal segments anchylosed together;
8d. LimuluSf M&lier, having a head composed of 7 cephalic and one
thoracic segments, followed by 6 coalesced thoracic somites bearing
branchiae, and one or more coalesced abdominal somites, to which is artic-
ulated the telson.''

From this I infer, that Mr. Woodward proposes to separate as a new
genus under the name Prentwichia^ those species formerly referred to
BellinuruSy in which the body segments are anchylosed together. If so,
our Illinois species would fall into the latter group, under the name
Prestmchia Dance*

3. Ser.tion of the Hocks of Illinois, from WorthetCs Geological Re-
port, vol. II, 'p. viii.

PoaT-TERTiAKT. Feet

Drift) Loess, etc. — Clay, aaod, pebbles, boulders, etc. 160

Tbrtiabt.

Eoeene period f Clays and greenish sand, 160

Cabbonipkeous Strtbm.
OarboniferoM period. Coal-measures and MillstoDe grit. — Coal, shale, clay,

iimestoDes, sandstones nnd cooglomerate 1200

Mounlaih Limenione or Subearboni/erout period. Chester group. — Limestone,

sandstone and shale, 800

St. Louis beds. — Limestone and shale, SCO

Keokuk group. — Limestone and shale, 160

Burlington group. — Coarse, subcrystalline limestone, 200

Kindernook group. — Shales, limestone, sandstone, etc 160

Dkyorian Ststkh.

Hamilton period. Genesee division. — " Black slate" and grayish shale, 100

Hamilton beds. — Dark grayish fetid and lighter, more pure limestones, 120
Upper Helderberg period. Comiferous and Onondaga beds. — Gray, more or

less sandy limestone, 26

Oriekany period Oriskany — upper bed. — Quartzose sandstone, ... 40

Oriskany — lower beds, or Clear-creek group. — Highly siliceous, very
cherty msgnesian limestone, usually in thin layers 200

Uppee Silurian.

Lower ffelderberg period Lower Helderberg group, (D. shaly limestone of
N. T. geologists). — More or less magnesian and argillaceous lime-
stone, in thin layers, including flinty concretions, 200

Ntagara period, Niagara group. — Magnesian and argiUaceous limestones,. . . 200

LowKB Silurian.

KHndnnati period. Cincinnati group. — Limestones, shales and sandstone,. . . 140

Trenton period. Galena and Trenton bed8.~MagneBian and more or less pure

limestones, 800

Potsdam or Primordial period. St Peter's division. — Pure quartsose sandst, 160

120

Oaldferous division. — ^Magnesian limestones and sandstones, .^^„

** Been.

* Since the publication *of the Illinois Report, I observe Quenstedt figures, on
tab. 21, fig. 7, of his Handb. der Petref., under the name Oampeonyx fimbriaiu*, a
little Crustacean from the Coal-measures of Germany, almost certainly congeneric
with an imperfect specimen referred by us, provisionally, to our Palceocari» typua,
(See III. Rep., ii, pi. xxxn, fig. ba.) If Jordan's original figure, however, of the type of
the ^nus Oampeonyx, as reproduced by Pictet, and that given by Bn)nn, are even
nearly accurate, the typical specimen of our genus PaUtoearie must be yery dis^
tinct from Gmnps^nyg.



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Mineralogy and Geology. 309

4. Ckologieal Survey of Canada, — Catalogue of ike Sflurian Foeeih
of the Isle of Anticoeii^ with deecriptions of some new genera and epe^
cie$; by £. Billings, Paleontologi^U F.G.S. 93 pp., 8vo, with 42 wood-
cuts. Montreal, Nov., 1806. — The whole number of species enumera-
ted and described in ibis valuable memoir is about 830, of which some
130 are here for the first time made known to Science. Altogether they
represent over 10 genera of Protozoa^ Badiata, Afollueca^ and Arliculata,
Of these genera, the following are new, viz., lechyrima^ — a genus of bi-
valves apparently allied to the Trigoniidoe ; Sirepiocerae, a Cephalopod
like Ormoeeras but with a trilobate aperture like Pkragmoeerae^ — and
Sanichmtes^ supposed to be the trac*.ks or trails of a Mollusk. In enu-
merating the species previously described, full references are given to
the woncs in which the descriptions were originally published ; while
the larger portion of the new species are illustrated by good wood-cuts,
printed in the text

In regard to his genus Paseeolus^ published some time back, the
author says be thinks the evidence upon which it has been referred by
others to the Cgstidea, not conclusive ; and he denies that he had, as
some have thought, regarded it as presenting Ascidian affinities. He
also doubts its identity with Cgeloerinus of Eichwald.

On pages 75 to 82, be has some highly interesting and instructive rfr*
marks on the paleozoic rocks and fossils of Anticosti and New Bruns-
wick, and their relations to those of Canada, New York and Great Brit-
ain. It would be impossible to give here, even an intelligible abstract of
the whole of these remarks ; but it is worthy of note that he places the
Si, John^s group of New Brunswick, consisting of about 3000 feet of
Black slates and Sandstones (conformably underlaid by a series of rocks
very like the Cambrian) beneath the Potsdam sandstone^ and on a paral-
lel with the Lower Lingula flags of Wales. He mentions seeing, from
the St. John's group, species of Orthia^ Paradoxides^ Conocephalitee^
Arionehlue,, Microdiecua and Agnostus,

The Potsdam sandstone he considers divisible into lower and upperi
the first or lower division being represented by the sandstones and lime-
stones of the north shore of the Straits of Belle* isle, and the rocks, which
in Vermont are called the Georgia slates^ and Red sandstone character^
ized by Olenus Vermontana, O. Thompsom^ Conocephalites Adatnei, ^o.,
also probably including the St. John's slates (of Jukes) Newfoundland,
and the Paradoxides beds near Boston.

The upper Potsdam he views as being composed of the Minnesota and
Wisconsin trilobite beds, and probably the upper part of the Potsdam
sandstone of Canada and New York.

The Calciferous he likewise divides into lower and upper, the first
being the original typical Calciferous beds, and the latter (not known in
Can^a or New York) occurring in Newfoundland, where it is over 1000
feet in thickness.

Above the latter he places the L^vis formation, and next the Silery,
Between the L6vis and the Calciferous formations, there is a great pa-
leontological break, as there is also between the L^vis and the Chazj
above, many of the Trilobitee in the L^vis being closely allied to those
of the Upper Lingula flags and Tremadoc slates.



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This work will be indispensable to those wishing to study the rods
and (bswils of Anticasti, as well as highly interesting, from the general
bearing of sorae of the author's \iews, to all engaged in investigaUng the
Silurian rocks everywhere.

5. Tertiary of North and South Carolina ; by T. A. Conrad. (From
a letter to one of the editors, dated Philadelphia, Jan. 31, 1867!) — The
Tertiary strata of North and South Carolina are well worthy of a mofe
iborongh study than they have yet received. Prof. Tuomey has described
some disturbed Eocene strata in South Carolina, in which he finds many
specimens of the following Cretaceous forms: Ammonites plaemtOj Tere-
bratula Ifarlaniy Oryphoea mutabilis, and Spondylns greffalie, fie re-
marks (hat the beds containing these fossils are of the same age as the
conglomerate at Wilmington, N. C. That this mixture of Cretaceous and
Bocene species is accidental is clearly proved by their never having been
found in the undisturbed strata of older Eocene in Alabama and Missis-
sippi, and especially by the occasional presence of Cretaceous fossils in
the Miocene of Cape Fear river, N. C. No one would believe that they
Kved through the Eocene period ami escaped nlive into that of the Mio-
eene. Prot^ Emmons remarks that Belemnitella mucronata^ Exogym



Online LibraryJohn AlmonThe American journal of science and arts → online text (page 30 of 102)