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\ " De la Formation du FaHus."



THE BIOLOGICAL SCIENCES AND MEDICINE. 803

contrasted witli ancient physiology, lie was misled by the natural
temptation to carry out, in all its details, a parallel between the ma-
chines with which he was familiar, such as clocks and pieces of hy-
draulic apparatus, and the living machine. In all such machines there
is a central source of power, and the parts of the machine are merely
passive distributors of that power. The Cartesian school conceived
of the living body as a machine of this kind ; and herein they might
have learned from Galen, who, whatever ill use he may have made of
the doctrine of " natural faculties," nevertheless had the great merit
of perceiving that local forces play a great part in physiology.

The same truth was recognized by Glisson, but it was first promi-
nently brought forward in the Hallerian docti'ine of the " vis insita "
of muscles. If muscle can contract without nerve, there is an end of
the Cartesian mechanical explanation of its contraction by the influx
of animal spirits.

The discoveries of Trembley tended in the same direction. In the
fresh-water Hydra no trace was to be found of that complicated ma-
chinery upon which the performance of the functions in the higher
animals was supposed to depend. And yet the hydra moved, fed,
grew, multiplied, and its fragments exhibited all the powers of the
whole. And, finally, the work of Caspar F. Wolff,* by demonstrating
the fact that the growth and development of both plants and animals
take place antecedently to the existence of their grosser organs, and
are, in fact, the causes and not the consequences of organization (as
then understood), sapped the foundations of the Cartesian physiology
as a complete e"xpression of vital phenomena.

For Wolff, the physical basis of life is a fluid, possessed of a "vis
essentialis " and a " solidescibilitas," in virtue of which it gives rise to
organization ; and, as he points out, this conclusion strikes at the root
of the whole iatro-mechanical system.

In this country the great authority of John Hunter exerted a simi-
lar influence ; though it must be admitted that the two sibylline ut-
terances which are the outcome of Hunter's struggles to define his
conceptions are often susceptible of more than one interpretation.
Nevertheless, on some points Hunter is clear enough. For example,
he is of opinion that " spirit is only a property of matter " (" Introduc-
tion to Natural History," p. 6), he is prepared to renounce animism
{loc. cit.y p. 8), and his conception of life is so completely physical
that he thinks of it as something which can exist in a state of combi-
nation in the food. "The aliment we take in has in it, in a fixed
state, the real life ; and this does not become active until it has got
into the lungs ; for there it is freed from its prison " (" Observations
on Physiology," p. 113). He also thinks that "it is more in accord
with the general principles of the animal machine to suppose that
none of its effects are produced from any mechanical principle what-
* ''Thcoria Gencrationis ," 1759.



8 04 THE POPULAR SCIEXCE MONTHLY.

ever ; and that every effect is produced from an action in the part ;
which action is produced by a stimulus upon the part which acts, or
upon some other part wath which this part sympathizes so as to take
up the whole action " (loc. cit., p. 152).

And Hunter is as clear as Wolff, with whose work he was proba-
bly unacquainted, that " w^hatever life is, it most certainly does not
depend upon structure or organization " {loc. cit., p. 114).

Of course, it is impossible that Hunter could have intended to deny
the existence of purely mechanical operations in the animal body.
But while, with Borelli and Boerhaave, he looked upon absorption,
nutrition, and secretion as operations effected by means of the small
vessels, he differed from the mechanical physiologists, who regarded
these operations as the result of the mechanical properties of the small
vessels, such as the size, form, and disposition of their canals and aper-
tures. Hunter, on the contrary, considers them to be the effect of
properties of these vessels which are not mechanical, but vital. " The
vessels," says he, "have more of the polypus in them than any other
part of the body," and he talks of the " living and sensitive principles
of the arteries," and even of the " dispositions or feelings of the arte-
ries. . . . When the blood is good and genuine the sensations of the
arteries, or the dispositions for sensation, are agreeable. ... It is then
they dispose of the blood to the best advantage, increasing the growth
of the whole, supplying any losses, keeping up a due succession, etc."
{loc. cit., p. 133).

If we follow Hunter's conceptions to their logical issue, the life of
one of the higher animals is essentially the sum of the lives of all the
vessels, each of which is a sort of physiological unit, answering to a
polyp ; and, as health is the result of the normal " action of the ves-
sels," so is disease an effect of their abnormal action. Hunter thus
stands in thought, as in time, midway between Borelli on the one
hand and Bichat on the other.

The acute founder of general anatomy, in fact, outdoes Hunter in
his desire to exclude physical reasonings from the realm of life. Ex-
cept in the interpretation of the action of the sense-organs, he will not
allow physics to have anything to do with physiology.

" To apply the physical sciences to physiology is to explain the
phenomena of living bodies by the laws of inert bodies. Now, this is
a false principle, hence all its consequences are marked with the same
stamp. Let us leave to chemistry its affinity, to physics its elasticity
and its gravity. Let us invoke for physiology only sensibility and
contractility." *

Of all the unfortunate dicta of men of eminent ability this seems

one of the most unhappy, when we think of what the application of

the methods and the data of physics and chemistry has done toward

bringing physiology into its present state. It is not too much to say

* " Anatomic Generale," t. i, p. 54.



THE BIOLOGICAL SCIENCES AND MEDICINE. 805

that one half of a modern text-book of physiology consists of applied
physics and chemistry ; and that it is exactly in the exploration of the
phenomena of sensibility and contractility that physics and chemistry
have exerted the most potent influence.

Nevertheless, Bichat rendered a solid service to physiological prog-
ress by insisting upon the fact that what we call life, in one of the
higher animals, is not an indivisible unitary archajus dominating, from
its central seat, the parts of the organism, but a compound result of
the synthesis of the sep'arate lives of those parts.

" All animals," says he, " are assemblages of different organs, each
of which performs its function and concurs, after its fashion, in the
preservation of the whole. They are so many special machines in the
general machine which constitutes the individual. But each of these
special machines is itself compounded of many tissues of very different
natures, which in truth constitute the elements of those organs " (loc.
cit, Ixxix). " The conception of a proper vitality is applicable only
to these simple tissues, and not to the organs themselves " {loc. cit.,
Ixxxiv).

And Bichat proceeds to make the obvious application of this doc-
trine of synthetic life, if I may so call it, to pathology. Since diseases
are only alterations of vital properties, and the properties of each tis-
sue are distinct from those of the rest, it is evident that the diseases of
each tissue must be different from those of the rest. Therefore, in
any organ composed of different tissues, one may be diseased and the
other remain healthy ; and this is what happens in most cases {loc. cit.,
Ixxxv).

In a spirit of true prophecy, Bichat says, " We have arrived at an
epoch, in which pathological anatomy should start afresh." For as
the analysis of the organs had led him to the tissues, as the physio-
logical units of the organism ; so, in a succeeding generation, the anal-
ysis of the tissues led to the cell as the physiological element of the
tissues. The contemporaneous study of development brought out the
same result, and the zoologists and botanists exploring the simplest
and the lowest forms of animated beings confirmed the great induction
of the cell theory. Thiis the apparently opposed views, which have
been battling with one another ever since the middle of the last cen-
tury, have proved to be each half the truth.

The proposition of Descartes that the body of a living man is a
machine, the actions of which are explicable by the known laws of
matter and motion, is unquestionably largely true. But it is also true
that the living body is a synthesis of innumerable ])hysiological ele-
ments, each of which may nearly be described, in Wolff's words, as a
fluid possessed of a "vis essentialis," and a "solidoscibilitas" ; or, in
modern phrase, as protoplasm susceptible of structural metamorphosis
and functional metabolism ; and that the only machinery, in the pre-
cise sense in which the Cartesian school understood mechanism, is that



8o6 THE POPULAR SCIENCE MONTHLY.

which coordinates and regulates these physiological units into an or-
ganic whole.

In fact, the body is a machine of the nature of an army, not of that
of a watch, or of an hydraulic apparatus. Of this army, each cell is a
soldier, an organ a brigade, the central nervous system headquarters
and field telegraph, the alimentary and circulatory system the commis-
sariat. Losses are made good by recruits born in camp, and the life
of the individual is a campaign, conducted successfully for a number
of years, but with certain defeat in the long-run.

The efficacy of an army, at any given moment, depends on the
health of the individual soldier, and on the perfection of the machinery
by which he is led and brought into action at the proper lime ; and,
therefore, if the analogy holds good, there can be only two kinds of
diseases, the one dependent on abnormal states of the physiological
units, the other on pertui'bation of their coordinating and alimentative
machinery.

Hence, the establishment of the cell theory, in normal biology, was
swiftly followed by a " cellular pathology," as its logical counterpart.
I need not remind you how great an instrument of investigation this
doctrine has proved in the hands of the man of genius, to whom its
development is due ; and who would probably be the last to forget
that abnormal conditions of the coordinative and distributive machin-
ery of the body are no less important factors of disease.

Henceforward, as it appears to me, the connection of medicine with
the biological sciences is clearly defined. Pure pathology is that
branch of biology which defines the particular perturbation of cell-life,
or of the coordinating machinery, or of both, on which the phenomena
of disease depend.

Those who are conversant with the present state of biology will
hardly hesitate to admit that the conception of the life of one of the
higher animals as the summation of the lives of a cell aggregate,
brought into harmonious action by a coordinative machinery formed
by some of these cells, constitutes a permanent acquisition of physio-
logical science. But the last form of the battle between the animistic
and the physical views of life is seen in the contention whether the
physical analysis of vital phenomena can be carried beyond this point
or not.

There are some to whom living protoplasm is a substance even such
as Harvey conceived the blood to be, " summa cum providentia et
intellectu infinem certum agens, quasi ratiocinio quodam " ; and who
look, with as little favor as Bichat did, upon any attempt to apply the
principles and the methods of physics and chemistry to the investiga-
tion of the vital processes of growth, metabolism, and contractility.
They stand upon the ancient ways ; only, in accordance with that
progress toward democracy which a great political writer has declared
to be the fatal characteristic of modern times, they substitute a repub-



THE BIOLOGICAL SCIENCES AND MEDICINE. 807

lie formed by a few billion " animulae " for the monarchy of the all-
pervading " anima."

Others, on the contrary, supported by a robust faith in the univer-
sal applicability of the principles laid down by Descartes, and seeing
that the actions called "vital" are, so far as we have any means of
knowing, nothing but changes of place of particles of matter, look to
molecular physics to achieve the analysis of the living protoplasm itself
into a molecular mechanism. If there is any truth in the received
doctrines of physics, that contrast between living and inert matter, on
which Bichat lays so much stress, does not exist. In nature, nothing
is at rest, nothing is amorphous ; the simplest particle of that which
men in their blindness are pleased to call " brute matter " is a vast
aggregate of molecular mechanisms, performing complicated move-
ments of immense rapidity and sensitively adjusting themselves to
every change in the surrounding world. Living matter differs from
other matter in degree and not in kind ; the microcosm repeats the
macrocosm ; and one chain of causation connects the nebulous original
of suns and planetary systems with the protoplasmic foundation of life
and organization.

From this point of view, pathology is the analogue of the theory
of perturbations in astronomy ; and therapeutics resolves itself into
the discovery of the means by which a system of forces competent to
eliminate any given perturbation may be introduced into the economy.
And, as pathology bases itself upon normal physiology, so therapeu-
tics rests upon pharmacology ; which is, strictly speaking, a part of
the great biological topic of the influence of conditions on the living
organism and has no scientific foundation apart from physiology.

It appears to me that there is no more hopeful indication of the
progress of medicine toward the ideal of Descartes than is to be de-
rived from a comparison of the state of pharmacology, at the present
day, with that which existed forty years ago. If we consider the
knowledge positively acquired, in this short time, of the modus ope-
randi of urari, of atropia, of physostigmin, of veratria, of casca, of
strychnia, of bromide of potassium, of phosphorus, there can surely be
no ground for doubting that, sooner or later, the pharmacologist will
supply the physician with the means of affecting, in any desired sense,
the functions of any physiological element of the body. It will, in
short, become possible to introduce into the economy a molecular
mechanism which, like a very cunningly contrived torpedo, shall find
its way to some particular group of living elements, and cause an ex-
plosion among them, leaving the rest untouched.

The search for the explanation of diseased states in modified cell-
life ; the discovery of the important part played by parasitic organ-
isms in the etiology of disease ; the elucidation of the action of medi-
c^aments by the methods and the data of experimental physiology ;
appear to me to be the greatest steps which have ever been made



8o8 TEE POPULAR SCIENCE MONTHLY.

toward the establishment of medicine on a scientific basis. I need
hardly say they could not have been made except for the advance of
normal biology.

There can be no question, then, as to the nature or the value of the
connection between medicine and the biological sciences. There can
be no doubt that the future of pathology and of therapeutics, and
therefore that of practical medicine, depends upon the extent to which
those who occupy themselves with these subjects are trained in the
methods and impregnated Avith the fundamental truths of biology.

And, in conclusion, I venture to suggest that the collective sagacity
of this congress could occupy itself wath no more important question
than with this : How is medical education to be arranged, so that,
without entangling the student in those details of the systeraatist
which are valueless to him, he may be enabled to obtain a firm grasp
of the great truths respecting animal and vegetable life, without which,
notwithstanding all the progress of scientific medicine, he will still find
himself an empiric ?



PEOGKESS m THE MANUFACTUEE OF STEEL.*

By Peofessoe A. K. HUNTINGTON.

IMPROVEMEXTS in the arts and sciences have gradually modified
the methods of producing iron and steel, and, in their turn, the
arts and sciences have felt the reaction ; for all improvements in the
manufacture of iron and steel have consisted, not so much in the pro-
duction of a better quality of the article, as in the cheapening of pro-
duction by the application of the principles indicated by the progress
of science, and by the use of superior machinery. The direct result
of this cheapening has been to extend the applications of the products
in the arts.

The discovery of steel appears to have naturally followed that of
the means of reducing iron from its ore. In all primitive methods of
iron-smelting, steel, in more or less quantity, is inevitably produced.
Such methods have been carried on in India and Africa from time im-
memorial to the present day. A furnace of a similar primitive charac-
ter has, for several centuries, been employed in Catalonia, in Spain.

In working this furnace, the ore is crushed by the hammer, and
divided by sifting into lumps {mine) and very coarse powder {greil-
lade). The furnace being still red-hot from the last operation, it
is filled with charcoal nearly to the tuyh'e, the hearth is then di-
vided at a point about two thirds distance from the tuyere into two
parts by a broad shovel ; on the blast-side a further quantity of char-

* xibridged from an address delivered before the London Society of Arts.



PROGRESS AV THE MANUFACTURE OF STEEL. 809

coal is added, while the coal on the other side having been rammed
down firm, ore is added, so as to fill that part of the furnace ; on this
is placed moistened charcoal-dust, except at the top. A good blast is
then turned on, and, if the whole is in proper order, jets of blue flame
at once issue from the uncovered portion of the ore.

During the whole of the process, at short intervals, greillade
and charcoal are added, and well moistened with water, to prevent
too rapid combustion. After about two hours from the commence-
ment, the wall of mine, i. e. — ore in lumps — is pushed well forward
under the tuyere, and more mine is thrown into the space thus
made ; this part of the process is also subsequently repeated at inter-
vals, until sufticient has been added to form a lump of iron or masse
of the required size. From time to time slag is removed by opening
the tap-hole. At the completion of the process, a mass of metal is
obtained weighing about three hundred-weight, which invariably con-
sists partly of soft iron, and partly of steely iron and steel.

The ore on one side of the furnace being in lumps, the hot carbonic
oxide generated by the action of the blast on the charcoal is able to
pass freely through its mass, reducing it, after the water has been
driven off by heat, to metallic iron. At the same time the ore becomes
impregnated with carbon, derived from the decomposition of the gases
with which it is charged. The greillade on the other side is much
richer in silica than the larger pieces, and from this it results that the
quantity of slag will vary with the greillade added. It is always very
rich in oxide of iron. It appears that in this process, carburized iron
is produced by the gradual reduction and fusion of the lumps of ore,
and this, coming in contact at the bottom of the furnace with slag,
very rich in oxide of iron, the carbon of the one combines with the
oxygen of the other, and the result is that iron containing more
or less carbon is produced, according as much or little oxide was
present.

In order that steel may be produced by this process, every precau-
tion is taken to cause as much carburization as possible ; the unavoid-
able presence of oxide of iron in the slag, and the low temperature,
effectually preventing the formation of cast-iron ; the former, indeed,
making it very diflicult to obtain steel.

Kightly looked at, this process exj^lains how steel was first ob-
tained, and what the essential conditions are in its production. When,
owing to the increased size of blast-furnaces, and the consequent in-
crease of temperature, cast-iron became the only product, it naturally
followed that this substance should be treated with a view to the
production of steel. This was first effected in the refining hearth, and
formed an important industry in Styria, Carinthia, the Tyrol, and
otlier places, in some of which it is still carried on. The operation
was conducted in a finery, similar in construction to those employed
in tlic production of iron — in fact, iron and steel are often produced



8io THE POPULAR SCIENCE MONTHLY.

alternately in the same finery. This furnace, in its simplest form,
consists essentially of a shallow quadrangular hearth, formed of cast-
iron plates. In one side is a tuyere, inclined at an angle of 10° to
15°. The bottom is kept covei'ed with a layer of charcoal. In the
Siegen district, a piece of pig-iron, weighing fifty to sixty pounds, is
placed on the hearth, having been previously heated ; the hearth is
then three parts filled with burning charcoal ; on it is placed a portion
of the cake produced in the last operation, which has been kept hot in
burning charcoal, at the back of the furnace. The remainder of the
hearth is then filled up with charcoal. The other six or seven pieces
into which the last cake w^as divided are placed on the top. In this
process, the production of steel and the reheating of that obtained in
the last operation, preparatory to working it under the hammer, are
conducted together. The blast is turned on. The piece of pig-iron
forms into a pasty mass ; cinder, rich in oxide of iron, produced in the
latter part of the preceding operation, is then thrown in ; a second
piece of pig-iron, weighing about one hundred pounds, is added, and
afterward four or five pieces of spiegeleisen (cast-iron, containing
manganese), weighing each about a Inmdred pounds, are successively
added. If the metal is found to be too much decarburized, more
Spiegel is added. In this process, as in the Catalan, it is impossible to
obtain a homogeneous product. The principle in both is essentially
the same, viz., decarburization by oxide of iron. In this process, as in
every other process for the production of steel, manganese is used
with great advantage — an advantage which arises from its power of
replacing iron in the slag and of forming a slag that is more liquid
than one containing iron alone.

The essential difference between the finery and the puddling proc-
ess consists in the use of a reverberatory furnace, the manipulation
of the metal and the regulation of the temperature being thereby
greatly facilitated. The decarburization is effected by the addition
of oxide of iron produced during rolling, and partially by the air
which enters the furnace as the metal melts slowly down ; manganese
is added during the process. It is important that the temperature
should be kept low. It is difiicult to weld this steel perfectly, because,
probably, the temperature at which it has to be worked is too low to
make the cinder sufficiently liquid to enable it to be squeezed out
under the hammer to the same extent that it is in the case of malle-
able iron. This difficulty has, however, been got over by completely
fusing the steel before working it, so as to enable the slag to separate
completely. In this form metal manufactured by this process has
been largely used by Krupp.

The principle which regulates the production of steel by these
methods is taken advantage of in the Uchatius process, in which pig-
iron is first granulated by running it while molten into cold water. The
granulated metal is then mixed with about twenty per cent, of roasted



PROGRESS IX THE MANUFACTURE OF STEEL. 811

spathic ore, crushed fine ; the mixture, to which a little flux has been
added, if necessary, is then fused in clay crucibles. If very soft steel
is required, some wrought-iron scrap is added.

Lastly, in this category we have a process which consists in heat-
ing cast-iron, but not so as to soften it, in oxide of iron, in the form
of ore or iron-scale. In this way partial, or even total, decarburiza-
tion of the metal can be produced at will.



Online LibraryD. S. (David Samuel) MargoliouthThe Popular science monthly (Volume 19) → online text (page 101 of 110)