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" Upper Ten," " Magnolia," " Extra Choice," " Golden Drip," " White-
Loaf Drip," etc. Dealers tell me that these sirups, by their cheapness
and excellence, have driven all the others out of the market. So much
is this the case that it is no longer proper to call glucose the " coming
sirup." It is the sirup which has already come.

In addition to the uses above mentioned, small quantities of glu-
cose are used by vinegar-makers, tobacconists, wine-makers, distillers,
mucilage-makers, and perhaps for some other purposes.

Grape-sugar is also used for many of the purposes enumerated above,
but chiefly for the adulteration of other sugars. When it is reduced
to fine powder, it can be mixed with cane-sugar in any proportions,
without altering its appearance. Since the grape-sugar costs less than



GLUCOSE AND GRAPE-SUGAR. 255

half the price of cane-sugar, this adulteration proves immensely profit-
. able. The presence of grape-sugar in table-sugars can be approxi-
mately determined by several simple tests. When placed on the
tongue, the bitter after-taste, already spoken of, may be detected. If
spread in a thin layer on a piece of glass, and treated with a little
water, the cane-sugar granules dissolve first, and the grape-sugar is
left as a flocculent mass. With the microscope, its particles can be
detected by the absence of all crystalline structure. Its exact quan-
tity can only be determined by the polariscope. This is hardly a
proper place to describe how this is done.

From the best information I can obtain, it appears that the cost of
manufacture of glucose and grape-sugar is about one cent a pound.
From twenty-six to thirty-two pounds are made from a bushel of
corn. It is sold by the manufactories at three to four cents per
pound. In the West the price of corn during the last year has
averaged a little over thirty cents per bushel. It thus appears that
the manufacture of glucose is a profitable industry.

I shall attempt here no detailed statement of the method of
manufacture, but give only such an outline as may interest those
who like to know how the things on their tables are prepared. The
corn is first soaked for two or three days in warm water, and is then
ground on specially prepared stones with a stream of water. The
meal is next passed into a trough, the bottom of which is made of
fine bolting-cloth. Here the starch is washed through, and led ta
large tanks, where it is allowed to settle. It is next beaten up with
caustic soda to separate the gluten, and the starch is again allowed
to settle in long, shallow troughs. The starch, washed from all ad-
hering alkali, is next beaten up with water into a cream, and con-
ducted into the converting-tubs. These tubs are supplied with coils
of copper steam-piping and are made of wood. Here the starch-
cream is treated with dilute sulphuric acid, and steam is allowed to
bubble up through the mixture from small holes in the copper pipes.
This process of conversion, which is called " open conversion," is com-
pleted in about two hours.

Another method is called " close conversion." The substances are
inclosed in stout copper cylinders, and subjected to the action of super-
heated steam. This process occupies about fifteen minutes.

The conversion is also accomplished sometimes by fermentation.
This requires a much longer time. The greater part of it, however,
is carried on by the method first named.

After conversion the acid is neutralized by marble-dust and animal
charcoal. Since the sulphate of calcium, which is formed in this oper-
ation, is slightly soluble in water, carbonate of barium has been used
instead of marble-dust. Its use, however, has not become general.

After neutralization the liquid is filtered through cloth and animal
charcoal, and is then conveyed to the vacuum-pan. Here it is evapo-



256 THE POPULAR SCIENCE MONTHLY.

rated, at as low a temperatiire as possible, to tlae required concentra-
tion. If grape-sugar is to be made, the process of conversion is not
stopped as soon as the starch has disappeared, but is carried on still
further to a point which can only be determined by trial. After con-
centration it is conveyed into tanks, where the process of solidification
begins and continues for several days.

Glucose, on the other hand, will not harden, whatever the degree
of concentration may be, or, at least, if it do so, only partially and
after many months.

The habit of bleaching both glucose and grape-sugar by means of
sulphurous acid is sometimes practiced, but is reprehensible. By the
oxidation of the sulphurous acid, free sulphuric acid is likely to occur
in the finished product.

Glucose and grape-sugar are mixtures of several chemical sub-
stances. Starch, which is composed of six atoms of carbon, ten of
hydrogen, and five of oxygen, when subjected to the action of dilute
sulphuric acid, appears to undergo a molecular condensation and hy-
dration. Among the substances formed may be reckoned dextrine,
glucose, and a substance isomeric with cane-sugar. This latter sub-
stance appears to be one of the early products of conversion, and this
is the reason that the poorly converted glucoses are sweeter than the
well converted. It is only after prolonged boiling with dilute acid
that the product becomes chemically homogeneous, with a constitution
which is probably represented by the symbol CgHj^OgH^O,

Glucose presents several anomalies when examined with polarized
light. Its highest rotatory power is found when it is made with the
least possible amount of conversion — i. e., when the process of con-
version is stopped as soon as the starch has disappeared. Continued
boiling with dilute acid causes a gradual decrease of rotatory power.
It is only after six to eight hours* heating to a temperature of 104° C.
that a constant rotatory power is reached. This power is only about
half that exhibited by the glucose as a maximum. This minimum,
rotatory power, however, is greater than that possessed by cane-sugar.

Glucose, like many other bodies, has the property of reducing a hot
alkaline copper solution and separating the metal as a red sub-oxide.
This power in glucose is always inversely as the rotating power. I
have shown this fully and conclusively in the paper already referred
to. The relation between reducing power and rotating power is a con-
stant one, and hence the percentage of reducing power can be calcu-
lated from the polarimetric observations. This, however, is of more
interest to the practical chemist than to the general reader, and I there-
fore pass it by.

The question of most practical importance is, " Is glucose a whole-
some article of food?" I do not hesitate to answer this question
in the affirmative. I mean by this, however, a glucose which is
properly made. Such a glucose contains only a very little sulphuric



THE MENTAL EFFECT OF EARTHQUAKES. 257

acid and lime, not much more than good spring-water, and perhaps
an ahnost infinitesimal trace of copper, so slight as only to be de-
tected in a large quantity of the substance. I do not doubt but
that glucoses have been sold which contain large quantities of free
sulphuric acid and likewise other injurious ingredients. But these are
due to carelessness in manufacture, and are not constituents of the
genuine article. I have never found a glucose of this kind. Many of
the impurities which have been imputed to glucose, really belong to
the cane-sirups with which they have been mixed. These largely
adulterated glucoses should always be looked upon with suspicion.
The cane-sirups, which are used for this purpose, yield from three to
five per cent, of ash, while the ash from a genuine glucose is so little
as to be almost unweighable.

There is no reason to believe that a glucose or grape-sugar prop-
erly manufactured is any less wholesome than cane- or maple-sugar.
Corn, the new American king, now supplies us with bread, meat, and
sugar, which we need, as well as with the whisky which we could do
without.



THE MENTAL EFFECT OF EAETHQUAKES.

THE outbreak of new earthquakes, first at Agram, then in Ischia,
and now in Chios, the last the most destructive of all, and cost-
ing thousands of lives, within a few weeks of each other, seems to
show that a period of earthquake-shock may have begun which may
affect, to an extent by no means inconsiderable, the history and life of
our century. No one can doubt that the earthquakes and volcanic
eruptions which visited the same general region, but more especially
Asia Mmor and Italy, during the first and second centuries of our era,
produced great effects, not only on the minds and characters of that
generation, but even on the distribution of population ; nor that the
earthquake at Lisbon, in the last century, produced almost as great a
shock on the thoughts of men as it produced physically on the im-
mense region over which its effects were felt — a region which included
almost all Europe, part of Africa, and part of the American Continent.
A spell of earthquake of any violence or duration, which should ex-
tend over such a field as that, would, in a time like our own, when
every influence is intensified by the simultaneous transmission of the
impressions it produces to all parts of the globe, produce the most
powerful effects, not simply on the countries which might suffer from
it, but on all the world. No physical phenomena, however dreadful,
seem to produce the same sense of paralysis as earthquakes. A corre-
spondent of Captain Basil Hall, who was in the earthquake of Copiapo,

VOL. XIX. — 17



258 THE POPULAR SCIENCE MONTHLY.

in 1822, describes the effect on the mind as something which begins
before any other sign of the earthquake has manifested itself at all —
an anticipatory horroi-, which is even more marked in the case of the
lower animals. " Before we hear the sound, or at least are fully con-
scious of hearing it, we are made sensible, I do not know how, that
something uncommon is going to happen ; everything seems to change
color ; our thoughts are chained immovably down ; the whole world
appears to be in disorder ; all nature looks different to what it is wont
to do ; and we feel quite subdued and overwhelmed by some invisible
power, beyond human control or apprehension." In the Neapolitan
earthquake of ISO."), these anticipatory signs were most remarkable in
relation to the life of the animal world. An Italian writer, quoted in
Mr. Wittich's " Curiosities of Physical Geography," says : " I must
not omit in this place to mention those prognostics which were derived
from animals. They were observed in every place where the shocks
were such as to be generally perceptible. Some minutes before they
were felt, the oxen and cows began to bellow, the sheep and goats
bleated, and, rushing in confusion one on the other, tried to break the
wicker-work of the folds ; the dogs howled terribly, the geese and
fowls were alarmed and made much noise ; the horses which were fast-
ened in their stalls were greatly agitated, leaped up, and tried to
break the halters with which they were attached to the mangers ;
those which were proceeding on the roads suddenly stopped, and
snorted in a very strange way. The cats were fi-ightened, and tried
to conceal themselves, or their hair bristled up wildly. Rabbits and
moles were seen to leave their holes ; birds rose, as if scared, from the
places on which they had alighted ; and fish left the bottom of the
sea and approached the shores, where at some places great numbers
of them were taken. Even ants and reptiles abandoned, in clear day-
light, their subterranean holes in great disorder, many hours before
the shocks were felt. Large flights of locusts were seen creeping
through the streets of Naples toward the sea the night before the
earthquake. "Winged ants took refuge during the darkness in the
rooms of the houses. Some dogs, a few minutes before the first shock
took place, awoke their sleeping masters, by barking and pulling them,
as if they wished to warn them of the impending danger, and several
persons were thus enabled to save themselves." What it is, before
the sound or shock of earthquake is felt, which warns both animals
and human beings of the approach of some dreadful catastrophe threat-
ening the very basis of their existence, no one, of course, can say, since
the impression made upon the nervous system is, at least as regards
our own species, evidently one of general disturbance, and not one to
which experience attaches any explicit significance. It may be, of
course, that some very great change in the magnetic conditions of a
spot threatened with earthquake leads to that extreme excitement of
mind exhibited by all living creatures previous to the onset of the



THE MENTAL EFFECT OF EARTHQUAKES. 259

earthquake. That, however, is pure conjecture. What is interesting
is, that a certain blank consternation seems always to be the charac-
teristic herald of an earthquake, as well as the characteristic result.
That it should be the characteristic result is, of course, no wonder.
The very condition of human life is the solidity of the not very thick
earth-crust on which we live, and when that solidity is exchanged for
positive fluidity, as it is in the worst earthquakes, it is natural enough
that stupefaction should be the result. In one of the Calabrian earth-
quakes, it was discovered that large pieces of ground had so changed
places that a plantation of mulberry-trees had been carried into the
middle of a corn-field and there left, and a field sown with lupines had
been carried out into the middle of a vineyard. The Italian lawsuits
which resulted from this liquefaction of "real" property may be easily
imagined. Still stranger, in the earthquake in Riobamba in 1797,
Alexander von Humboldt found that the whole furniture of one house
had been buried beneath the ruins of the next house. " The upper
layer of the soil, formed of matter not possessing a great degree of
coherency, had moved like water in running streams, and we are com-
pelled to suppose that those streams flowed first downward, and at
last rose upward. The motion in the shocks which were experienced
in Jamaica (July 7^ 1692) must have been not less complicated. Ac-
cording to the account of an eye-witness, the whole surface of the
ground had assumed the appearance of running water. The sea and
land appeared to rush on one another, and to mingle in the wildest
confusion. Some persons who, at the beginning of the calamity, had
escaped into the streets and to the squares of the town, to avoid the
danger of being crushed under the ruins of the falling houses, were so
violently tossed from one side to the other that many of them received
severe contusions, and some were maimed. Others were lifted up,
hurled through the air, and thrown down at a distance from the place
where they were standing. A few who were in town were carried
away to the seashore, which was rather distant, and then thrown into
the sea, by which accident, however, their lives were saved." Such
a liquefaction of all that is most solid in our world seems a grim
enough realization of the prayer of the prophet : " O that thou
wouldst rend the heavens, that thou wouldst come down, that the
mountains might flow down at thy presence," for the mountains do
really flow down in earthquakes, but the effect of that flowing is a
consternation such as no other phenomenon of physical life, not even
the worst darkness of volcanic eruptions, ever produces. The loss of
everything stable at the basis of human life is the collapse of the ordi-
nary foundations even of the spiritual life itself, though, if that life
has got its roots firmly into the heart, the original foundations may
fall away without impairing the vitality of that which at first had
propped itself upon them. But, where this is not the case, nothing
tends more to that truest Nihilism — which, so far from thinking it



26o THE POPULAR SCIENCE MONTHLY.

worth while to destroy anything, finds both destruction and construc-
tion alike childish under the tottering of the very pillars of life — than
the phenomena of an earthquake. Amid the moral shocks which the
collapse of the very earth itself produces, only a faith which has pro-
foundly convinced itself that the physical frame of things is a mere
scaffolding, by the lines of which the spiritual dwelling of man has
been fashioned, remains at all. Positivism itself, with its hierarchy
of the sciences, all of them resting on the material life as the substra-
tum of everything, would obviously disappear in a moment along with
the menace to that physical foundation on which it bases its whole
system.

It is curious to think what such races as the Teutonic would be-
come under the influence of frequent earthquakes. Their " solidity " of
character, as it is called, largely consists in the confidence they feel in
the sameness of all Nature's ways ; and whether it would survive that
confidence, and outlive the constancy on which it was nourished, is
very doubtful. An English squire, for instance, whose timber and
crops had changed places with the timber and estates of his next
neighbor, would certainly not be recognizably an English squire much
longer. An English merchant, whose stock of satins or teas had van-
ished under the establishment of his rival, would find the world so
very much out of joint that he himself would probably become an
unmeaning phenomenon. It is, indeed, clear that even rare periodical
attacks of earthquake would render the existence of a great capital
impossible, and the character of an agricultural population quite dif-
ferent, and probably much more capricious than before. And not
unreasonably so. Spiritual faith, even if it remain, can not well rule
the actions of physical beings in a physical world which has lost all
aspects of constancy. Indeed, repeated shocks to the physical basis
of things, though they may well test the strength of faith, can not of
course be often repeated on this earth of ours without transferring all
the characteristic operativeness of faith to a world of another kind.
Faith is faith in divine constancy ; and the constancy which has ceased
to govern oiir bodies must be discoverable in some other region, not
that of our bodies, if faith is to be of use. Morally, then, the only
use of earthquakes must be to test the growth of a spiritual faith in a
world and life beyond the reach of earthquakes. Clearly it can not
strengthen or educate such a faith. It can only sift the false faith
from the true, and accord to the true its triumph. — Spectator.



SKETCH OF JULIUS ADOLPH STOCKHARDT. 261
SKETCH OF JULIUS ADOLPII STOCKHAEDT.

By Professor W. O. ATWATER.

A FEW miles from Dresden, iu one of the many picturesque re-
gions of Saxony, cozily stowed away at the confluence of three
lovely valleys, lies the little village of Tharandt, known to a few pleas-
ure-seekers as a charming summer resort, and to the world at large
as the seat of a famous school of forestry and agriculture. On an
eminence overlooking the village, and itself overlooked by the pictu-
resque ruin of what was once a hunting-castle of the princes of Sax-
ony, is the house ; in the village below are the school, the laboratory,
and the experiment station ; and hard by are the experimental garden
and fields where the subject of our sketch, Julius Adolph Stock-
HARDT, lives and labors. For nearly forty years he has been engaged,
by researches, by lectures, by writing, and by the publishing of jour-
nals, in promoting and popularizing the science of chemistry, especially
in its applications to the culture of the soil. In carrying science to
the people, and in presenting it in such ways that the most learned
can not criticise nor the most ignorant fail to understand, that every
one who reads or listens shall wish to read or listen more, and that
the facts when comprehended may be successfully and profitably ap-
plied to practice, few living men are his peers. And, as an author
as well as interpreter of researches, Stockhardt ranks among the
ablest of the early leaders in this, the golden age of agricultural
chemistry.

He was born at Rohrsdorf, near Meissen, in Saxony, January 4,
1809. After receiving a classical education, he studied pharmacy and
the natural sciences for several years, and was graduated in 1833 as
an apothecary of the first class. In 1834 he traveled in Belgium, Eng-
land, and France, then devoted himself to pharmaceutical study and
research, and in 1838 received the degree of Ph. D. from the Univer-
sity of Leipsic. He then entered upon the teachin'g of natural science
in Dresden, and afterward in the technological school at Chemnitz, and
was also appointed inspector of apothecaries. His rare talent for
presenting scientific knowledge of matters usually obscure was soon
recognized by both students and citizens, and the remai'kable power
of critical obsei'vation displayed in his writings (" Untersuchung der
Zwickauer Steinkohle," 1840; "Ueber Erkennung und Anwendung
'lor Giftfarbe," 1844, etc.) was the occasion of almost innumerable
applications for the investigation of commercial problems, and de-
mands for his opinion upon scientific and legal questions. In 1843
he traveled in Belgium and France to perfect himself in technologi-
cal science. In 184G he published his " Schule der Chemie," which in



262 THE POPULAR SCIENCE MONTHLY.

1861 had reached its twelfth edition ; had been translated into eight
different languages, and was used by scores of thousands of students
the world over. The current American translation of this work,
" Stockhardt's Principles of Chemistry," is very widely and pleasantly
known among teachers and students in this country.

In 1844 StGckhardt began a course of popular agricultural lectures
before the Chemnitz Agricultural Society. To these lectures may be
traced the beginning of the movement which, eight years later, resulted
in the establishment at Mockern, Saxony, of the first of the agricult-
ural experiment stations, of which there are now over one hundred in
Europe and several in the United States, and from whose work, it may
be said without exaggeration, has emanated a great part — perhaps the
greater part — of our accurate knowledge of the principles of chem-
istry and physiology that underlie the right practice of agriculture.
On the occasion of the celebration, in 1877, of the twenty-fifth anni-
versary of the founding of the Muckern Station, three albums, with
photographs of the directors of the experiments at that time estab-
lished, were provided : one for the parent station at Mockern, one for
Professor von "Wolff, its first director ; and one for Professor Stock-
hardt in consideration of his services in founding and promoting that
and other stations.

From 1846 to 1849 Stockhardt was editor of the " Polytechnisches
Centralblatt," and from 1850 to 1855 of the "Zeitschrift fur deutsche
Landwirthe." In 1848 he was appointed Professor of Agricultural
Chemistry in the Royal Academy at Tharandt, where a new chair had
been founded purposely for him, and where he has since remained.
Since then, extending his idea of popular agricultural instruction, he
has given plain conversational lectures to farmers' clubs and societies
in Saxony and other parts of Germany, explaining the improvement
in agriculture which chemical science has shown to be desirable, and
illustrating them with experiments where practicable. The more im-
portant of these lectures have been published with the title " Che-
mische Feldpredigten " (" Chemical Field-Sermons "), and have been
translated into several languages. In 1855 he established at Leipsic
" Der chemische Ackersmann," a journal which was continued until
1876, when increase of years and cares, and the doing away of its
necessity by the establishment, with his aid, of another journal, "Die
Landwirthschaftlichen Yersuchs-Stationen," occasioned its discontinu-
ance.

But this brief outline of his career gives very little idea of Stock-
hardt as a man, an investigator, a teacher, and an expounder of the
occult facts of science. To know him in these relations one must see
him at his home, among his friends, in his study, his laboratory, his
lecture-room, with students and farmers, and must read him in his
books.

In appearance and demeanor he is plain and quiet. In social inter-



SKETCH OF JULIUS ADOLPH STOCKHARDT. 263

course he is approachable, kind, ready for a pleasantry, a laugh, or
to impart from the great store of his learning whatever the earnest
inquirer may need. In the lecture-room his talk is so simple and



Online LibraryD. S. (David Samuel) MargoliouthThe Popular science monthly (Volume 19) → online text (page 32 of 110)