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with each other. The slave-making ants
{Pol>/erffics lucidus) were studied near Altoo-
na, Pennsylvania. They occupied a cham-
bered nest which was furnished with four

■ gates, and extended to the depth of at
least twenty-two inches underground; but

1 the chambers were without orderly arrange-
ment, apparently on account of the grav-

i elly nature of the soil in which they were
built. Mingled in large numbers with the
lucidus ants were working insects, of the
species Formica Schaujfitssi. Two days
after the nest was disturbed, the work-
ing ants were observed cleaning out the
galleries, with the apparent intention of
closing the openings. Others were engaged
in a migration, taking up the mistress ants
by interlocking mandibles with them, and
carrying them off up the perpendicular face
of the cutting for eighteen or twenty inches,
and then for the distance of six feet over the
ground and through the grass. " More than
once a slight opposition was made to this
treatment. The slaves, or at least certain
individuals of them, . . . seemed at times
to have a prejudice against the presence of
hicidm ants above-ground, and would un-
ceremoniously seize them and carry them



130



THE POPULAR SCIENCE MONTHLY.



below. I have seen a master, or more prop-
erly ' mistress,' thus served several times,
each time returning in a dogged sort of
resistance to the will of her servitor.
These inert mistresses, too, apparently know
something of the bitterness of bondage to
a capricious domestic help ! " In the course
of the migration, one queen was seen to re-
sist carriage so vigorously that she was
finally dropped, and, refusing to give the
slave a hold on the mandibles, was seized
by the wing and dragged off. " The luci-
dies ants seemed to have no volition in or
direction of this movement. I released a
number from their porters during various
stages of the transit, and they always wan-
dered about with a confused, aimless, and ir-
ritated manner until again seized and borne
off by slaves." Some of the ants were col-
onized in Philadelphia, and observed more
closely. The masters were never seen to
work. "The colony was changed several
times in order to incite to new work in min-
ing galleries and rooms ; clusters of lucidus
were placed by themselves ; they always re-
mained idle. The slaves wrought with the
greatest industry and energy as long as
there was any need: the masters would
crowd into the galleries, and move about in j
an aimless way, but I never could trace any I
attempt either at directing or aiding in the
work. So, also, I never saw one attempt to i
eat. . . . Yet they are in good condition,
and evidently well fed. They arc doubtless
fed by the workers, who must disgorge the
food." But Dr. McCook could not see this
going on. The lucidus ants and the workers
both seemed fond of the light, even of the
artificial warmth and light of the gas-light
globe, where they would " congregate in the
comfortable glow." The association of the
two species in their singular relations has
resulted in developing the warlike faculties
of lucidus at the expense of its disposi-
tion to labor ; but has not operated to de-
generate the soldierly courage and faculty
of Formica Schauff'ussi, the working ant,
for the individuals of this species will spring
to repel a hostile attack as freely and fierce-
ly as their masters, and will do it indepen-
dently, too ; and they are quite as able as
ready to wage sucessful warfare. The hici-
dm ant appears to be spread over the whole
continent, except perhaps in the far south.



Improved Electric Motor. — A new form
of dynamo-machine has recently been de-
vised by Mr. C. F. Ileinrich, which the " Tel-
egraphic Journal " pronounces an important
advance upon previous constructions. The
main improvement is in the form of the
armature, which the inventor has been led
to adopt by a careful study of the Gramme
ring and the way in which currents are in-
duced in it. He finds that the inner side of
the ring (that farthest from the field mag-
net) produces on the coil a current opposed
to the one induced on the part of the coil
immediately in front of the poles of this
magnet, and to this extent weakens the cur-
rent and causes heat in the coil. When the
field magnet is powerful and the ring thin,
this effect is reduced, but the inductive ac-
tion of the farther side of the ring is not
wholly eliminated. He therefore makes the
ring channeled, or of horseshoe cross-sec-
tion, the coils of wire being wound on the
outside only. This removes the metal from
the inner portion, and at the same time
allows such a free circulation of air around
the wires of the coil where they cross the
base of the horseshoe that heating is effect-
ually prevented. The ring is mounted and
revolved between the poles of the field mag-
net in the same way as on the Gramme ma-
chine.

Geological Features of Behrin^ Strait.

— Some curious geological features are
noticed in Mr. W. H. Call's report of his
last summer's work in the coast and geo-
detic survey of Alaska and the vicinity of
Behring Strait. The country is not wholly
without attractions, for when, on the 20th
of August, the surveying-vessel, the Yukon,
anchored behind Cape Lisburne, on the
American shore of the Arctic Ocean, nearly
two hundred miles north of Behring Strait,
the air was balmy, the sun was warm and
bright, no snow or ice was visible, and the
banks were covered with flowers, among
which daisies, monk's hoed, and forget-me-
nots were conspicuous. At Point Belcher,
too, the vegetation was quite dense. Beds
of good coal, belonging to the true Car-
boniferous period, are found at Cape Lis-
burne, from which the revenue cutter Cor-
win was satisfactorily coaled several times.
Large lumps of coal lay on the beach at



POPULAR MISCELLANY.



131



Point Belcher, which had been pushed up
by the ice from the bottom of the sea. The
peculiar geological feature of this region is a
great formation of ice which seems to have
the characteristics of a regularly stratified
rock. At Point Belcher, pure ice is met at
two feet below the surface, and is of un-
known depth. At Elephant Point, Kotzebue
Sound, the clay banks gradually rising along
the beach to the eastward show successively
two perpendicular faces of ice, " solid and
free from mixture of soil, except on the out-
side," one above the other. The ice-face
nearest the beach is covered with a coating
of soil which bears a luxuriant vegetation.
The whole formation, including the talus in
front of the ice, may be about thirty feet
high. Above this is a second talus, on a
larger scale, ascending to the foot of another
iec-face, which is also covered with herbage-
bearing soil. The brow of the second bluff
is about eighty feet above the sea ; from it
the land rises gradually to a rounded ridge
three or four hundred feet high. At the
height of two hundred and fifty feet a
frozen stratum was found containing lumps
of clear ice, that indicated the existence of
solid ice, at no great depth below. Hence
it is inferred that the whole ridge, two miles
wide and two hundred and fifty feet high, is
chiefly composed of solid ice overlaid with
clay and vegetable mold. The ice gener-
ally has a semi-stratified appearance, is only
superficially soiled, is granular in structure
for the outer inch or two, and internally
solid and transparent or slightly tinged with
yellow ; but is never greenish or bluish, like
glacier-ice. Small pinnacles of ice run up
into the clay in places, while in other places
the ice itself is penetrated with deep holes in
which clay and vegetable matter have been
deposited. Holes were seen in the clay-
molds of spurs of ice that had been melted
away, and cylinders of muck and clay were
found on the ice-face, that had once filled
holes from around which the ico had melted.
A strong, p:culiar smell was often noticed,
apparently emanating from dark, pasty spots
in the clay. It was supposed to proceed from
the decompasition of the remains of soft
parts of mammoths and other animals.
Birches and alders seven or eight feet high,
luxuriant herbage, and plants bearing deli-
cious berries, grew with their roots less than



a foot from perpetual solid ice. Observations
en the water in the strait showed that it is
warmest toward the American side, and be-
comes gradually cooler toward the Asiatic
side ; that the temperatures are nearly uni-
form from top to bottom, precluding the idea
of the existence of a sub-surface current
from the Arctic Ocean which carries cold
water to the south ; and that the northerly
current through the strait and along the
Arctic Ocean is probably chiefly dependent
on the tide for its force and direction, and
upon the warming of shallow waters for its
high temperature.

Minnesota Academy of Sciences. — The

Minnesota Academy of Sciences was organ-
ized seven years ago, and is now free from
debt, and able to report its library and cab-
inet in creditable condition. Although it
has had to encounter a lack of sympathy
from part of the community, on account of
an apprehension that its tendency might be
toward infidelity, the retiring President, Dr.
F. L. Hatch, declared at the annual meeting
last January, that in none of the papers
read and published under the sanction of
the Academy had any dogma of any one's
faith been touched, or a derogatory reflec-
tion been cast upon the Christian's sacred
record. Professor N. H. Winchell, the in-
coming President, made an address at the
annual meeting, maintaining the right and
duty of the State to establish and support
institutions for the higher education. He en-
deavored to show that the denominational
colleges and universities had been backward
in responding to the demand for the pro-
vision of more liberal courses of scien-
tific in.struction ; and that no general move-
ment was made by them in this direction
till a sj-stem of scientific schools had been
established by private enterprise and State
aid, independently of them, and in the face
of their indifference to the scheme.

Units of Eleotrlcal Measurement.— The

International Congress of Electricians, to be
held in Paris during the summer, will doubt-
less be called upon to consider the subject
of a uniform standard for electrical measure-
ments. The system of standards at present
most used was adopted by the British Asso-
ciation after eight years of study and expori-



132



THE POPULAR SCIEXCE MONTHLY.



ment by a committee. In it all the units
of measurement are referred to three funda-
mental unit3, the centimetre, the gramme,
and the secund, whence it is called the centi-
metre-gramme-secund system of units (ex-
pressed by the symbol C. G. S.). The units
practically employed — multiples or sub-mul-
tiples of the fundamental units — are the
ohm, or unit of resistance (symbol R.), the
volt, or unit of electro-motive force (symbol
E.), and the weber, or unit of intensity (sym-
bol I.). Their relation to each other is ex-

F
pressed by the equation, I = - , whence, the

value of two of the elements being known,
that of the other can be determined. The
unit of resistance, or ohm, is determined by
a long and complicated formula, so that it is
easier to get it at once by comparison with
the material standard which is kept at Lon-
don. Graduated resi.stancc-boxes containing
electric coils carefully adjusted to the resist-
ance-force they are intended to represent,
are sold by the instrument-makers. Some
idea of what the ohm is may be given by
saying that a wire of pure copper a metre
(or S9i inches) long and a milimeter in di-
ameter (or about -^g of an inch) represents a
resistance of one fiftieth of an ohm ; conse-
quently, fifty metres, or one hundred and
fifty and a half feet of such wire, will repre-
sent an ohm. Common copper wire offers
a stronger resistance, so that only thirty or
forty metres of it are required to represent
an ohm. The volt, or unit of electro-motive
force, is not represented by any actual exact
standard, but several constant piles exist,
the force of which has been exactly meas-
ured, which may be referred to. A Daniell
battery, having its copper immersed in a
saturated solution of sulphate of copper,
and its zinc in a saturated solution of sul-
phate of zinc, has a force of 1"079 volt. The
electro-motive force may be measured in
practice by using galvanometers which are
graduated in volts, the exactness of which is
proportioned to the amount of the resistance
they offer. One weber represents the in-
tensity of a current having a force of a volt
and passing over a circuit which offers an
ohm of resistance. The intensities of cur-
rents in ordinary industrial use are repre-
sented by fractional units of the weber, the
milliwcber, or thousandth of a weber, for tel-



egraphic, domestic, and medical currents,
the microwcber, or millionth of a weber, for
telephonic currents. Telegraphic currents
vary in intensity from five to twenty milli-
webers ; the currents of the Gramme ma-
chines that feed the Serrin regulators, of
from twenty to thirty webers. Some ma-
chines used in electrotyping afford still more
intense currents, often exceeding eighty we-
bers, although their electro-motive force is
very feeble. In France they sometimes
measure by the kilometre of resistance,
meaning by that the resistance which is
offered by a telegraphic wire four millime-
tres or about one sixth of an inch in di-
ameter, and a thousand metres or five fur-
longs long, which is equivalent to about ten
ohms. The unit of Siemens (U. S.), employed
in Germany, represents the elastic resist-
ance of a column of mercury having the
length of a metre and a section of a square
millimetre, and is equivalent to 0'9536 of an
ohm. Several units of intensity founded on
the chemical action of electric currents are
in use — such, for example, as may be found-
ed on the quantity of gases disengaged in a
minute by a voltameter placed in a circuit,
or the amount of copper that may be de-
posited in an hour in an electrolytic bath
which is traversed by the current to be
measured. Standard apparatuses have also
been made, bo graduated as to furnish on a
simple reading the intensities in webers and
microwebers.

German Anthropology. — The German
anthropologists are making a study of
the relative distribution of blondes and
brunettes in aid of their investigation of
the origin and ethnological composition of
the German people. The reports on this
subject, presented by Professor Virchow to
the recent German Anthropological Con-
gress, seemed to indicate the existence of
centers of light-colored populations in
Schloswig-Hol stein, the country of the low-
er Elbe, Hanover, and Pomerania, and of
dark-colored stocks in Bavaria, along the
Rhine, in western Belgium, and in Switzer-
land. No superiority over the other is as-
cribed to either complexion, but the differ-
ence is one of original stocks. The blondes
appear to have come down from the north-
cast of Europe and pressed the native dark



POPUL AR MIS CELL ANY.



133



race upon the mountain-spurs and the upper
valleys. Herr Eckert reported to the Con-
gress conceruing the progress he had made
in determining the differences in the skulls
of the sexes. The feminine skull appears
to be marked by a smaller volume, greater
delicacy in the contours of the orbits and
the structure of the jaws, the absence or
inferior importance of the frontal sinus, a
more gradual passage from the forehead to
the root of the nose, and a flattening of the
parietal bone. A discussion took place re-
specting some Arabic silver ornaments and
filigrees of the tenth and eleventh centuries
which have been found in Northern and
Eastern Europe. Virchow has concluded,
from the occurrence of these articles, that
an extensive trade existed in the ninth and
tenth centuries between the regions of the
Volga, the Baltic ports, and the northern
countries, and the coasts of the Black Sea
and the East. These Arabic ornaments are
very abundant in the province of Posen,
in some parts of Russia, and in Gothland,
and Arabic coins are found in Norway and
Iceland. A paper was presented by Pro-
fessor Ranke, based on the statistics of
reci-uits for the year, which appeared to
show that a relation exists between the
character of the country and the size of the
men who inhabit it. The higher mountain-
regions appear generally to produce the
larger men. M. Kollmann, of Switzerland,
read a paper showing that prognathism,
which is believed to be an exclusive mark
of inferior races, is of frequent occurrence
among civilized people. The prognathous
jaws which have hitherto been found in
Europe have been considered as abnormal
cases, or as examples of alveolar progna-
thism ; but it is impossible exactly to sepa-
rate alveolar from real prognathism. Some
skulls from the heart of Germany, by what-
ever rules or lines they are measured, show
a greater degree of prognathism than those
of the negroes of Australia ; and the con-
clusion can not be avoided that this feat-
ure is shared to a considerable extent by
civilized people. An interesting communi-
cation was made concerning the skull of
Emmanuel Kant, whose remains had been
exhumed in order to place them in the
tomb built for them by the city of Kiinigs-
berg. Two skeletons were found together,



but the remains of Kant were identified by
comparing the skull with the cast which was



I preserved in the archives of Konigsberg,
with which it was found to correspond ex-
actly. The bones of the nose were turned
toward the right, and the superciliary arch
had a greater development on the same side.
The greatest cranial length was 182 milli-'
metres, the height 132 millimetres, and the
breadth 161 millimetres, while the mean
breadth of Prussian skulls is only 1446
millimetres. The forehead had none of the
majesty attributed to a thinker; it was not
broad, and was a little retreating. The tem-
ples had a fullness that compensated for
this lack, and the left temple showed a pro-
tuberance in the region of the third frontal
circumvolution, the region in which the fac-
ulty of controlling articulate speech is sup-
posed to reside. The only extraordinary
feature of the face was the height of the
orbits.

Life and Xatnre in the Campos. — Dr. D.

Christison's narrative of his journey to cen-
tral Uruguay, given before the Royal Geo-
graphical Society last fall, is full of curious
illustrations of the primitive character of
the life in a country which, although it has
great capacities for development, is as yet
hardly known abroad. The region to which
the description applies is the estancia of San
Jorge, on the south bank of the Rio Negro,
almost in the center of the republic, which
embraces an area of three hundred and
sixty-four square miles. The journey from
Montevideo was made in a diligencia, an open
omnibus in three compartments, holding
twelve passengers, and drawn by six half-
broken or unbroken horses, which are driven
in a manner peculiar to the Campos. In or-
der to prevent accidents from unperceived
faults in the roads, a cuartiador rides about
twenty yards ahead of the team and conducts
it by means of a rope which at one end is
fastened to the wagon-pole and loosely con-
nected with the bridles of the leaders, and
at the other end is attached to the saddle of
his own horse. The stages are short, but
the stops are very long, for the horses have
to be driven in from the plain, and much
talking has to be done before those which
are needed are lassoed and harnessed to the
wagon. "Sometimes an animal is selected,



134



THE POPULAR SCIENCE MONTHLY.



which has never been harnessed or handled
before, and it is only after a long struggle,
requiring the utmost skill and strength of
the mayoral and his assistants, that it is sub-
dued, great roughness being used in lassoing
and throwing it, while it is approached and
handled gently in harnessing." The road,
like all the main routes in Uruguay, is
called the camino real, or. royal road, but the
roads are all mere tracks over the Campos,
chosen so as to avoid the steepest hills
and seek the easiest places to ford the
rivers. As a rule, the country can be
crossed by ordinary stage-coaches on the
natural turf in either direction. The land-
scape is tame and monotonous, disposed for
the most part in low, gently sloping downs
or ridges, rising from sixty to two hundred
feet above the valleys, " covered with grass
and generally unbroken by tree, bush, or
rock." The ridges are not furrowed by
ravines, and show no traces of erosion.
Signs of human habitation are rare. In a
few instances the view was relieved by
two or three ombie-trees {Phytolacca dioica),
" large, handsome, shady trees, with soft,
pith-like stems." Near Florida we're ob-
served groups of stones, like cairns, " con-
sisting of squarish blocks arranged in an
artificial-looking manner," a similar forma-
tion to which, fifty miles farther west,
called Serra, constitutes a true though min-
iature raountain-range, and has been com-
pared by Dr. Burmeister to the " Teufels-
mauem " and " Felsenmeere " of Germany.
The district of San Jorge, judging from the
rocks of the dividing ridges, rests on a for-
mation of volcanic origin, and is remarkably
well watered by the Rio Xegro and its tribu-
taries, the Garpinteria and Chileno, with nu-
merous streams flowing through it. The
mass of the country is covered with grass
but destitute of timber, while the rivers are
fringed with monies, dense belts of trees and
shrubs. The grass is coarse and bunchy,
endures the droughts of ordinary summers,
and is profusely adorned with composifce,
yellow and purple oxalis, white, red, and
scarlet verbenas, many liliaceous plants, and
a fine cenothera. The only native tree on the
Campos is a thorny tala ( Celtis tola). The
mo7ites are of comparatively insignificant
area, and are composed chiefly of willows,
coronillos, laurels, the fruit-bearing gua-



yavo, prickly climbers, and brush-wood,
comprising more than twenty species in all.
The larger animals — the jaguar, puma, great
ant-bear, and large deer — have nearly dis-
appeared, but the smaller animals and the
rodents are well represented. Birds are
numerous and extraordinarily tame. Eagles
would let the traveler throw clods at them
and almost touch them, and the rhea ostrich
would allow a man on foot to approach to
within seventy yards before walking or trot-
ting off. The most important insect is the
leaf-cutting ant, which has been often de-
scribed. It parcels out the Campos among
its communities, the nests of which are
generally about a hundred yards from each
' other, with five or six paths radiating from
' each till they approach the domains of
their neighbors. Along these paths double
' streams of workers are constantly passing
1 to and from the country, each ant of the
returning stream holding aloft a piece of
I grass, a leaf, or a flower. Gardens must
j be protected against them by destroying the
] nests with boiling water or poi.sonou3 solu-
j tions — a diflBcult task, which has to be care-
fully done. Another insect plague is the
bicho more, a blistering beetle, which at-
tacks the potato-fields and eats regularly
forward with almost incredible rapidity. —
The return-journey to Montevideo was made
in a bullock-wagon, a solidly built vehicle
with an arched roof of zinc, perched on
high, broad wheels made of pieces of wood
so skillfully wedged together that every
shock made them firmer, and drawn by
means of a shaft which is of one piece
with the body. The three or four yoke of
powerful oxen, which form the team, are
driven by a picador, who rides alongside,
and the whole train, of which a single one
of the wagons is only a member, is under
the command of a mounted carrctero, or
patron. The rate of traveling is estimated
at from twenty to twenty-four miles a day,
but is largely dependent on the weather.

Physiology of Arsenical Poisoning.—

MM. H. Caillet de Poncy and C. Livron, of
the Medical School at Marseilles, have found
that, when poisoning by arsenic takes place,
the phosphorus which exists as phosphoric
acid in the brain is replaced by arsenic.
The substitution takes place in Xhclccithinc,



POPULAR MISCELLANY.



35



a very complex nitrogenized compound,
which thus becomes transformed into an
insoluble albuminoid substance. In acute
poisoning there is no time for the arseni-
Tted lecithine to be subjected to physiologi-
cal reactions and be eliminated, and the



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