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D. S. (David Samuel) Margoliouth.

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animal dies under the local influence of the
poison without sensible variation of the nor-
mal phosphorus of the nervous matter. In
slow and chronic poisoning the replacement
takes place slowly; arseniated lecithine is
formed, and acts as ordinary lecithine, pass-
ing gradually into the insoluble albuminoid
state, while the phosphorus is steadily di-
minished, giving place to the arsenic.

The Otto of Roses.— The otto of roses
lonsists of an odoriferous liquid containing
oxygen combined with a solid hydrocarbon
called slearopiene, which is destitute of per-
fume. The quality of the oil is determined
by the relative proportion of these sub-
stances, and that is dependent chiefly on
conditions of climate. The Bulgarian oils
contain about eighteen per cent., the oils
distilled in France and England as much as
thirty-five and even sixty-eight per cent, of
stearoptene. The difiference in the propor-
tions is al.so shown in the higher tempera-
ture required to melt the oil which contains
a greater relative amount of stearoptene.
The Bulgarian oil melts at from 61" to 64°,
French and English oils from TO^ to 89^°.
Even in Bulgarian oil a notable difference
is observed between that produced on the
hills and that from the lowlands. The most
important source of otto of roses is a small
district in Bulgaria or East Roumclia, stretch-
ing along the southern slopes of the central
Balkans, and approximately included be-
tween the twenty-fifth and twenty-sixth de-
grees of east longitude and the forty-second
and forty-third degrees of north latitude.
A suitable soil for the growth of roses is
furnished, with need for but little manuring,
by the decomposition of the syenite, which
is the characteristic rock of the region.
The average summer temperatures of the
ilistrict arc 86^ at noon, and 68' in the
evening. The rose-bushes do best on sandy
slopes having a good exposure to the sun.
The flowers of bushes which grow on in-
clined ground are much richer in oil, and
that of a stronger quality, than those raised



on level land, and are therefore more es-
teemed and dearer. The flowers when fully
expanded are gathered before sunrise, often
with the calyx attached, and should be
treated the same day. In Bulgaria, rosea
which have matured slowly in moderately
cold weather furnish the richest yields ; in
England, the contrary appears to be the
case. The flowers are distilled for an hour
and a half, with double their volume of
water, in a copper still from which a pipe
passes through a tub that is kept constantly
cool by inflowing spring-water. After the
distillate has been allowed to stand for a
day or two at a temperature exceeding 59°,
the oil is skimmed off from it. The residual
liquors are used instead of spring-water for
subsequent distillations. The rose-water
which comes over last is extremely fragrant,
and is much prized for medical and culinary
purposes. Pure otto, carefully distilled, is
at first colorless, but speedily becomes yel-
lowish ; has a specific gravity of about 0-87,
boils at 444°, and solidifies at from 51-8° to
60-8', or at higher temperatures in the case
of inferior oils, and is soluble in absolute
alcohol. It is tested by its odor, which can
be judged only after long experience; its
congeal ing-point (a good oil should congeal
in five minutes at a temperature of 54'5°),
and by the crystallization of the stearoptene
with light, feathery, shining plates filling the
whole liquid. It is sometimes adulterated
with spermaceti, which may be detected by
its readiness to solidify, and by other essen-
tial oils, the effect of which is sometimes to
lower the congealing-point. Rose-water and
otto of roses are also produced in India ; in
Persia, where the trade, formerly important*
has nearly disappeared ; in the Mediterra-
nean countries of Africa, and in France.
The otto of the Provence rose has a char-
acteristic perfume, which arises, it is be-
lieved, from the pollen of orange-flowers,
which is brought by bees to the petals of
the roses.

Effefts of Pettlns on Animals.— Mr. A.

D. Bartlett, of the Zoological Gardens, Lon-
don, has remarked that while adult camiv-
orous animals— lions, tigers, leopards, etc.
— can seldom be tamed and then only at the
cost of danger, the young become very tame
and fond of those who feed and caresa



n6



THE POPULAR SCIENCE MONTHLY.



them; on the other hand, housed vegeta-
ble-feeding animals — stags, antelopes, oxen,
sheep, and goats — if reared by hand from
birth, become when adult the most danger-
ous animals to be met with ; while, if caught
after they have grown up, they are timid
and fly from man. His experience with all
animals of the latter class has been the
same as with the lamb, whose case he de-
scribes, that was brought up as " one of the
family." As it grew larger and stronger,
it became self-conscious and independent,
having "no fear and less gratitude," and
grew so saucy that it had to be consigned to
a large field, where it became a terror to
passers — for, " with hop, skip, and jump, he
was behiud any one in an instant ; with one
good spring, the unfortunate traveler was
on his hands and knees if not on his face "
— and was finally sentenced to the butcher.
Such of these animals as have been bred
in captivity (not petted and handled) and
reared by the parent, become exceedingly
wild if an attempt is made to catdh them,
pack them up, or move them from one place
to another. The reason for these curious
manifestations appears to be that the tamed
animals, having lost their fear of man and
become familiar with him, when the time
comes for them to manifest their belligerent
propensities, have no respect of persons,
and are ready to attack their former friend
as they would any other real or imaginary
antagonist ; but, when anything new is at-
tempted with them, it is as novel as it would
be in their natural state, and awakens all
their natural wildness.

FnngI as Inseftlfides.— The possibility
of putting a limit to the depredations of nox-
ious insects by cultivating the fungi which
are destructive to them has been several
times suggested. Professor Le Conte recom-
mended the study of the epidemic diseases
of insects, particularly of the fungoid dis-
eases, with this view, in 1874. Charles II.
Peck, State Botanist of New York, advanced
a similar idea with reference to the fungi
which infest plants, in 1876, and in 1878
described a large destruction of seventeen-
year-locusts and of the larvae of insects feed-
ing upon the alder by fungi. Dr. H. A. Ha-
gen, of Harvard University, in 1879, thinking
he had established the identity of the fungus



which destroys the house-fly with the yeast-
fungus, recommended the use of the latter
against noxious insects in general. Pro-
fessor A. N. Prentiss, of the Botanical Lab-
oratory, instituted a scries of experiments
during the spring of 1880 with the plants
in the laboratory, upon the effects of the
yeast-fungus upon the aphides and other
insects preying upon them. The record
of his experiments is given in the form of
a journal in contributions to " The Ameri-
can Naturalist." The result of nine experi-
ments as a whole, as also of many others
not recorded, indicates that yeast can not
be regarded as a reliable remedy against
such insects as commonly affect plants cul-
tivated in greenhouses and dwellings. The
attempt to use it is liable to the further
objection, that it will be very likely to in-
jure many kinds of plants quite as badly as
it will the insects. The experiments of Mr.
Trelease, of Selma, Alabama, with the yeast
upon the cotton-worm, led him to a similar
conclusion with reference to its application
to that insect. On the other hand, accord-
ing to Dr. Hagen, Mr. J. H. Hums, of Shel-
ter Island, New York, has had some success
with yeast against the Colorado potato bee-
tle, and it has been used upon the aphides
in a greenhouse in Germany with great suc-
cess. Professor Prentiss does not consider
the question at issue decided by his experi-
ments, for the yeast-fungus may be opera-
tive on other insects and under other condi-
tions than those with which he performed
his experiments, and there may be other
forms of fungus which, applied with discrimi-
nation, would be effective.

Examination of Germs in the .llr. — Dr.

Ferdinand Cohn and Dr. Jliflet, of Hreslau,
have been investigating experimentally as
to the possibility of detecting the organisms
which are regarded as the germs of infec-
tion and fermentation in the air in which
they are supposed to float. Their experi-
ments were carried on from the middle of
March to the end of July, 1878, in the air
of laboratories, operating-rooms, and the
sick-rooms of hospitals ; in the free air of
the botanical gardens, and the air gathered
at the surface of the soil of the garden ; and
in the sewer-air of a court. They found —
1. That numerous germs exist in the air in



P OP UL A R MIS CELL A NY.



137



a suitable condition to undergo develop-
ment ; 2. That these germs could be col-
lected by the methods they employed, could
be made to develop and multiply, and could
be systematically distinguished and de-
scribed ; 3. That the presence of some of
the germs which are commonly developed in
fermenting substances was not detected in
the air ; 4. That the presence of germs of
particular kinds was detected in air taken
from the surface of the soil; 5. That the
air of the sick-chamber of a typhus-hospital
appeared to be singularly free from germs
capable of development, a result which was
attributed to effective ventilation and dis-
infection ; 6. That the air rising from the
sewer was rich in living germs ; 7. That the
number of observations and experiments in
this their first systematic investigation is
not yet sufficient to enable them to deter-
mine whether the difference in the number
of germs collected from the air in different
places may be taken as indicating a differ-
ence in the healthiness of the several locali-
ties — so far, they seem to give a negative
result.

Forestry in India.— An address by Sir
William Temple, before the Society of Arts,
on " Forest Conservancy in India," calls at-
tention to the vast destruction of forests
which that country has suffered in common
with other populous. lands. Traditions show
that the country was once covered with syl-
van and other vegetation, but this dress has
been removed, as the demands of man upon
the surface have increased, and the most
important forest-growths are now found on
the mountain-ranges. The trees of India
may be divided into two classes ; those of
the Himalayas, and those of the other
mountain-ranges and the plains. The trees
of both classes are magnificent specimens
of growth. The Himalayan trees are allied
with those of Europe and other temperate
regions, and embrace, among the Coiiiferre,
tiie cedar, the Finus longifoUa, most valu-
able timber-trees; the cypress, the fir, the
yew, and tlie juniper, the latter the only valu-
able tree that grows near Quettah. Of the
other orders are the ile.T, oak, and walnut,
of Simia,the plane-tree of Cashmere, the ma-
ple, magnolia, laurel — here a great tree —
the rhododendron, and tho trof-f.-rn, most



graceful of plants. The other mountains
produce the teak, the iron-hearted sal, the
anjun, with its white, bright, and smooth
trunk like a great marble pillar ; the saj,
which often grows close by the anjun, and,
having a black and rough trunk, offers an
effective contrast with it ; the black-barked
bije sal ; and the white-barked, weird-look-
ing frankincense-tree. The plains furnish
the babul, or acacia, the one tree which is
universal in India; the mango, the figs,
among which are the banyan ; and the
India-rubber tree, bamboos, and palms in
their varieties. The demands of the popu-
lation for wood are immense, with thirty-
seven million houses in British India, and
one fifth as many in the native states, to be
supplied, and all the implements of a people
with whom iron is in comparatively little
use. On account of the scarcity of wood,
the people are obliged to burn manure for
■ fuel, and thus to rob the soil of what should
j be returned to it, adding another to the
agencies which are steadily impoverishing
it. The absence of woods can not affect the
total rainfall of the country, for the vapors
that rise from the sea must be condensed
somewhere, but it seriously affects its dispo-
sition. The clouds pass over the hot, dry
plains, and precipitate their moisture upon
the mountains, where they cause swift tor-
rents to rush down into the lower country
and create destruction there. The capacity
of the soil to retain moisture is destroyed,
and the water which would be stored in the
natural forest through the dry season is lost
in a sudden drought. A Forest Department
has been created by the Government within
the last tiiionty years, and gives special at-
tention to the preservation of the remaining
forests, of which the whole extent is about
seventy thousand square miles. These for-
ests are divided into the " reserves," or for-
ests which are carefully guarded, embracing
about twenty-five thousand acres, and the
" protected " forests, which are imperfectly
guarded and preserved. The forests of both
classes have been decided to be the prop-
erty of the Government. The reserves are
placed directly under the care of the Forest
Department. The protected forests are
managed by the ordinary civil officers, un-
der the supervision of the Forest Depart-
ment. The management is directed to the



138



THE POPULAR SCIENCE MONTHLY.



regulation of the cutting of timber, to the
control of the practice called " rab," or of
cutting the new shoots and twigs of trees
to be burned for manure, to the prevention
of jungle-fires, and to the regulation of
pasturage by establishing blocks, or areas
of forest range, to which grazing may be
confined, while other blocks are held in re-
serve to be entered upon after the grass of
the former blocks has been consumed. The
restrictions are imposed only in those forests
which have belonged from time immemorial
to the Government, as well under native
dynasties as under British rule; and, where
subordinate rights exist, they are recognized
and defined. Areas of jungle, of equal —
probably of more than eciual— extent with
the forests, and ample for the general local
use of the natives, have been evcrj-where
marked off as belonging to the people, and
are accessible to them without restriction.
The " reserved " and " protected " forests
furnish first and second class timber and
excellent fuel. The management of the
Forest Department has so far been attended
with a considerable profit to the revenue of
the state.

A New Disinfectant. — When warm air
is forced through a hot mixture of turpen-
tine and water, a disinfecting substance
known in commerce as sanitas is produced.
It is an aqueous solution, characterized by
the presence of peroxide of hydrogen and
certain camphoraceous substances. With it
is found another substance, called sanitas-
otl, also containing peroxide of hydrogen,
which possesses a high power of oxidation.
According to the account given of it by
Mr. C. T. Kingzett, the oil promises to be-
come very valuable for sanitary purposes.
As it has been found an efficient agent for
the decomposition of so stable a substance
as iodide of potassium, it can hardly be
doubted that it will also effect the oxida-
tion of any animal or vegetable substances,
particularly those which are in course of
putrefactive decomposition. It has also the
property of being capable, after having
once performed its measure of oxidation, of
forming a new amount of active peroxide
of hydropcn, which may be made available
for further work. Several experiments,
made by Mr. Kingzett, prove that this oil



is a powerful antiseptic. Beef put in wa-
ter containing it was kept sweet during pe-
riods of twenty-five and forty days; flour
paste from thirty to fifty days ; the whitL
of eggs for fifty days ; wine for one hun-
dred days. The oil is not destined to su-
persede the sanitas, for it is too powerful
in its action to serve the purpose to which
the aqueous solution is applied, and is not
adapted to meet the same ends, but be
a valuable supplement to it. It may be
added to glycerine, oils, or ointments, when
they are applied to the body in cases of
infectious disease. It may be evaporated
for the fumigation of rooms which have
been occupied by persons sufifering from
communicable diseases. Plane surfaces, as
floorings and walls, maybe disinfected 1 y
wiping them with a cloth or brush which
has been dipped in the oil ; and only a
small quantity of oil is necessary for this
purpose, for it spreads freely. It is slowly
volatile, and may be used as an aerial disin-
fectant. The emulsion in water may be
applied in a gi-eat many places ; and sprin-
kled over sawdust it may be emi)loyed as
an effective deodorant.

The Color-Sense among rnfivlllzed Peoples.

— Dr. Hugo Magnus, of Breslau, has just
published a work containing the results of
inquiries which he has made into the power
of uncivilized people to distinguish colors.
He sought to ascertain from direct evidence
the extent to which the color-sense already
exists among savages, and how great is its
capacity for development, and to collect the
terms by which they express their distinc-
tions of color. He prepared a set of ques-
tions relating to the most marked colors,
such as black, gray, white, red, orange, yel-
low, green, violet, and brown, omitting those
shades to distinguish which some degree of
education is obviously necessary, and sent
them to physicians, missionaries, merchants,
and other persons in different parts of the
world having intercourse with native races,
who seemed able to afford information on
the,subject. As a whole, he has found that
the color-sense of the ruder nations is cir-
cumscribed by limits differing but little
from those which bound the same sense
among civilized people. In no race did he
find an entire absence of the faculty of



POPULAR MIS CELL ANY.



139



distinguishing between the principal colors.
Taking red, yellow, green, and blue, as the
chief representatives of the colors of the
longer and shorter wave-lengths, there was
not one among the tribes coming within the
range of the inquiry which did not show
some knowledge of these four colors. This
knowledge must be considered as only rela-
tive, and not as existing in the same degree
a;nong all tribes. Savages exhibit impor-
tant differences in the degree to which their
sense of color is capable of cultivation,
h^omc show considerable skill in distinguish-
ing between different mixed and transitional
colors, others are less keen to perceive tran- I
sitional colors, while there are some who are
slow in marking the most distinct principal I
colors without being wholly incapable of it.
This dullness is shown chiefly in reference ,
to the colors of the shorter wave-lengths, '
as green, and more especially blue. There !
are tribes which have surprisingly little j
knowledge of these colors ; among them are
some of the aboriginal tribes of southern
India, whose color-sense is developed only
to the perception of red, while their knowl-
edge of yellow and green and blue is most
limited and rudimentary. The inhabitants
of the island of Nias have one name for
blue, violet, black, and green, another for
yellow and orange. Numerous observations
are cited to prove that the capacity to dis-
criminate between the colors of the longer
wave-lengths is sharper than that relative
to those of shorter wave-lengths. An Eng-
lish consul in the Loyalty Islands informs
Dr. Magnus that the inhabitants of that
group understand the differences between
colors very well, but confound them in nam-
ing them. The negro tribes of Sierra Leone,
distinguish between the several colors, and
have words to indicate them. Gray and
orange are least regarded, and are spoken
of as white and red. Blue and green are
frequently confounded, but are seldom men-
tioned as identical. The pastoral Ovahere-
ros, or Damaras, of South Africa, are keen
in their appreciation of the shades of color
that are marked on their cattle, and have
names for all of them, twenty-six terms in
all, but have no names for the colors that
are not cattle-colors, although they know
them apart quite clearly, and will use for-
eign words in speaking of them if it is



necessary. Sometimes, for lack of a better
word, they will use their own word for yel-
low, for blue, or green, but with a clear
sense that they are applying it inaccurately.
Most of the Damaras have come into some
contact with civilization, but no important
difference in the capacity to distinguish
colors can be found between the civilized
and the uncivilized members of the race.
The uncivilized, however, although they
know them well enough, can not give names
to blue and green, and think it strange that
these colors should need names. A tribe
on the Gold Coast are well acquainted with
the difference between red, yellow, green,
and blue, but are wholly destitute of terms
for the colors of the medium and shorter
wave-lengths, and seem to have names only
for white, black, and red. Virchow found
similar conditions to exist among the Nu-
bians, who were lately in Berlin, and a simi-
lar indifference to the colors of the middle
and shorter wave-lengths to prevail among
them. Most of them were accurate in per-
ceiving and naming the four higher colors
of the scale, and black, white, gray, and
red, but recognized the other colors with
some difficulty. Professor Delitzsch has re-
marked that the people of the ancient Se-
mitic races had little appreciation of blue.
This dullness in distinguishing the colors of
the shorter wave-length contrasts striking-
ly with the sharpness which people of all
races display in distinguishing and marking
red.

Slanghter of Food-.4iiiinals among the
Jews. — According to the analysis of Dr.
Rabbinonicz, of Paris, the Jewish Talmud-
ic rules concerning the slaughter of food-
animals were framed with the special ob-
ject of providing for the infliction of the
least possible suffering upon the animal,
and of procuring the meat in the most
wholesome condition for food. They pro-
hibit the stunning of the animal by a blow
on the forehead, because it is far from cer-
tain that the blow immediately annuls pain,
and it is certain that it does not annul it if
inflicted by an awkward hand. The rules
require that the act of killing shall be per-
formed by the sweep of a long, sharp in-
strument, which shall at once sever, more
or less completely, the trachea and oesoph-



140



THE POPULAR SCIENCE MONTHLY.



agus. They do not require the arteries to
be cut, for the nature of those vessels was
not known when the rules were made, but
the arteries and the important nerves around
their sheath are cut in practice, and the ani-
mal speedily faints into insensibility, and
dies of haemorrhage. The important points
of the code are, that the steps in slaughter
shall be continuous, because any interrup-
tion, however minute, in the process, is like-
ly to prolong the sufferings of the animal
and make it un6t for food ; that the cut
shall be made by a to-and-f ro stroke, with-
out any pressure beyond what is required to
carry the knife down to the necessary depth ;
that the incision in the skin shall accurately
coincide in length with the deeper portion,
so as to leave no " tail " to the wound ; that
the wound shall not be made so high as to
risk contact of the knife with the bony
structures above the cartilaginous rings of
the trachea, for this would be likely to cause
preventable suffering to the animal, and com-
pel the rejection of its flesh as food ; and
that no tissue should be torn or jagged. The
candidate for a license to slaughter has to
go through a long course of preparation,
of which a kind of rough anatomy forms a
part, and afterward to prove his compe-
tency to the satisfaction of the appointed
authorities. The heart is also carefully ex-
amined, to ascertain whether it is fit for
food. The rules on this subject, although
made before anything was accurately known
of pathology, contribute, as a whole, to the
selection of that which is good and to the
rejection of that which is bad. The use
of the blood is forbidden, and it is in
the blood that science to-day tells us the
germs and the matters that are detrimental



Online LibraryD. S. (David Samuel) MargoliouthThe Popular science monthly (Volume 19) → online text (page 18 of 110)