thought-power? Has the upper region called intelligence and reason, any
relations to physical force? This realm has not escaped the searching
investigation of modern science; and although in it investigations are
vastly more difficult than in any of the regions thus far considered,
yet some results of great value have been obtained, which may help us to
a solution of our problem. It is to be observed at the outset that every
external manifestation of thought-force is a muscular one, as a word
spoken or written, a gesture, or an expression of the face; and hence
this force must be intimately correlated with nerve-force. These
manifestations, reaching the mind through the avenues of sense, awaken
accordant trains of thought only when this muscular evidence is
understood. A blank sheet of paper excites no emotion; even covered with
Assyrian cuneiform characters, its alternations of black and white
awaken no response in the ordinary brain. It is only when, by a frequent
repetition of these impressions, the brain-cell has been educated, that
these before meaningless characters awaken thought. Is thought, then,
simply a cell action which may or may not result in muscular
expression—an action which originates new combinations of truth only,
precisely as a calculating machine evolves new combinations of figures?
Whatever we define thought to be, this fact appears certain, that it is
capable of external manifestation by conversion into the actual energy
of motion, and only by this conversion. But here the question arises,
Can it be manifested inwardly without such a transformation of energy?
Or is the evolution of thought entirely independent of the matter of the
brain? Experiments, ingenious and reliable, have answered this question.
The importance of the results will, I trust, warrant me in examining the
methods employed in these experiments somewhat in detail. Inasmuch as
our methods for measuring minute amounts of electricity are very
perfect, and the methods for the conversion of heat into electricity are
equally delicate, it has been found that smaller differences of
temperature may be recognized by converting the heat into electricity,
than can be detected thermometrically. The apparatus, first used by
Melloni in 1832,[32] is very simple, consisting first, of a pair of
metallic bars like those described in the early part of the lecture, for
effecting the conversion of the heat; and second, of a delicate
galvanometer, for measuring the electricity produced. In the experiments
in question one of the bars used was made of bismuth, the other of an
alloy of antimony and zinc.[33] Preliminary trials having shown that any
change of temperature within the skull was soonest manifested externally
in that depression which exists just above the occipital protuberance, a
pair of these little bars was fastened to the head at this point; and to
neutralize the results of a general rise of temperature over the whole
body, a second pair, reversed in direction, was attached to the leg or
arm, so that if a like increase of heat came to both, the electricity
developed by one would be neutralized by the other, and no effect be
produced upon the needle unless only one was affected. By long practice
it was ascertained that a state of mental torpor could be induced,
lasting for hours, in which the needle remained stationary. But let a
person knock on the door outside the room, or speak a single word, even
though the experimenter remained absolutely passive, and the reception
of the intelligence caused the needle to swing through 20 degrees.[34]
In explanation of this production of heat, the analogy of the muscle at
once suggests itself. No conversion of energy is complete; and as the
heat of muscular action represents force which has escaped conversion
into motion, so the heat evolved during the reception of an idea, is
energy which has escaped conversion into thought, from precisely the
same cause. Moreover, these experiments have shown that ideas which
affect the emotions, produce most heat in their reception; “a few
minutes’ recitation to one’s self of emotional poetry, producing more
effect than several hours of deep thought.” Hence it is evident that the
mechanism for the production of deep thought, accomplishes this
conversion of energy far more perfectly than that which produces simply
emotion. But we may take a step further in this same direction. A
muscle, precisely as the law of correlation requires, develops less heat
when doing work than when it contracts without doing it. Suppose, now,
that beside the simple reception of an idea by the brain, the thought is
expressed outwardly by some muscular sign. The conversion now takes two
directions, and in addition to the production of thought, a portion of
the energy appears as nerve and muscle-power; less, therefore, should
appear as heat, according to our law of correlation. Dr. Lombard’s
experiments have shown that the amount of heat developed by the
recitation to one’s self of emotional poetry, was in every case less
when that recitation was oral; _i.e._, had a muscular expression. These
results are in accordance with the well-known fact that emotion often
finds relief in physical demonstrations; thus diminishing the emotional
energy by converting it into muscular. Nor do these facts rest upon
physical evidence alone. Chemistry teaches that thought-force, like
muscle-force, comes from the food; and demonstrates that the force
evolved by the brain, like that produced by the muscle, comes not from
the disintegration of its own tissue, but is the converted energy of
burning carbon.[35] Can we longer doubt, then, that the brain, too, is a
machine for the conversion of energy? Can we longer refuse to believe
that even thought is, in some mysterious way, correlated to the other
natural forces? and this, even in face of the fact that it has never yet
been measured?[36]
I cannot close without saying a word concerning the part which our own
country has had in the development of these great truths. Beginning with
heat, we find that the material theory of caloric is indebted for its
overthrow more to the distinguished Count Rumford than to any other one
man. While superintending the boring of cannon at the Munich Arsenal
towards the close of the last century, he was struck by the large amount
of heat developed, and instituted a careful series of experiments to
ascertain its origin. These experiments led him to the conclusion that
“anything which any insulated body or system of bodies can continue to
furnish without limitation, cannot possibly be a material substance.”
But this man, to whom must be ascribed the discovery of the first great
law of the correlation of energy, was an American. Born in Woburn,
Mass., in 1753, he, under the name of Benjamin Thompson, taught school
afterward at Concord, N. H., then called Rumford. Unjustly suspected of
toryism during our Revolutionary war, he went abroad and distinguished
himself in the service of several of the Governments of Europe. He did
not forget his native land, though she had treated him so unfairly; when
the honor of knighthood was tendered him, he chose as his title the name
of the Yankee village where he had taught school, and was thenceforward
known as Count Rumford. And at his death, by founding a professorship in
Harvard College, and donating a prize-fund to the American Academy of
Arts and Sciences at Boston, he showed his interest in her prosperity
and advancement.[37] Nor has the field of vital forces been without
earnest workers belonging to our own country. Professors John W.
Draper[38] and Joseph Henry[39] were among its earliest explorers. And
in 1851, Dr. J. H. Watters, now of St. Louis, published a theory of the
origin of vital force, almost identical with that for which Dr.
Carpenter, of London, has of late received so much credit. Indeed, there
is some reason to believe that Dr. Watters’s essay may have suggested to
the distinguished English physiologist the germs of his own theory.[40]
A paper on this subject by Prof. Joseph Leconte, of Columbia, S. C.,
published in 1859, attracted much attention abroad.[41] The remarkable
results already given on the relation of heat to mental work, which thus
far are unique in science, we owe to Professor J. S. Lombard, of Harvard
College;[42] the very combination of metals used in his apparatus being
devised by our distinguished electrical engineer, Mr. Moses G. Farmer.
Finally, researches conducted by Dr. T. R. Noyes in the Physiological
Laboratory of Yale College, have confirmed the theory that muscular
tissue does not wear during action, up to the point of fatigue;[43] and
other researches by Dr. L. H. Wood have first established the same great
truth for brain-tissue.[44] We need not be ashamed, then, of our part in
this advance in science. Our workers are, indeed, but few; but both they
and their results will live in the records of the world’s progress. More
would there be now of them were such studies more fostered and
encouraged. Self-denying, earnest men are ready to give themselves up to
the solution of these problems, if only the means of a bare subsistence
be allowed them. When wealth shall foster science, science will increase
wealth—wealth pecuniary, it is true: but also wealth of knowledge, which
is far better.
In looking back over the whole of this discussion, I trust that it is
possible to see that the objects which we had in view at its
commencement have been more or less fully attained. I would fain believe
that we now see more clearly the beautiful harmonies of bounteous
nature; that on her many-stringed instrument force answers to force,
like the notes of a great symphony; disappearing now in potential
energy, and anon reappearing as actual energy, in a multitude of forms.
I would hope that this wonderful unity and mutual interaction of force
in the dead forms of inorganic nature, appears to you identical in the
living forms of animal and vegetable life, which make of our earth an
Eden. That even that mysterious, and in many aspects awful, power of
thought, by which man influences the present and future ages, is a part
of this great ocean of energy. But here the great question rolls upon
us, Is it only this? Is there not behind this material substance, a
higher than molecular power in the thoughts which are immortalized in
the poetry of a Milton or a Shakespeare, the art creations of a Michael
Angelo or a Titian, the harmonies of a Mozart or a Beethoven? Is there
really no immortal portion separable from this brain-tissue, though yet
mysteriously united to it? In a word, does this curiously-fashioned body
inclose a soul, God-given and to God returning? Here Science veils her
face and bows in reverence before the Almighty. We have passed the
boundaries by which physical science is enclosed. No crucible, no subtle
magnetic needle can answer now our questions. No word but His who formed
us, can break the awful silence. In presence of such a revelation
Science is dumb, and faith comes in joyfully to accept that higher truth
which can never be the object of physical demonstration.
------------------------------------------------------------------------
NOTES AND REFERENCES.
Footnote 1:
HUMBOLDT, Views of Nature, Bohn’s ed., London, 1850, p. 380. This
allegory did not appear in the first edition of the Views of Nature.
In the preface to the second edition the author gives the following
account of its origin: “Schiller,” he says, “in remembrance of his
youthful medical studies, loved to converse with me, during my long
stay at Jena, on physiological subjects.” * * * “It was at this period
that I wrote the little allegory on Vital Force, called The Rhodian
Genius. The predilection which Schiller entertained for this piece,
which he admitted into his periodical, _Die Horen_, gave me courage to
introduce it here.” It was published in _Die Horen_ in 1795.
Footnote 2:
HUMBOLDT, _op. cit._, p. 386. In his _Aphorismi ex doctrina
Physiologiæ chemicæ Plantarum_, appended to his _Flora Fribergensis
subterranea_, published in 1793, Humboldt had said “Vim internam, quæ
chymicæ affinitatis vincula resolvit, atque obstat, quominus elementa
corporum libere conjungantur, vitalem vocamus.” “That internal force,
which dissolves the bonds of chemical affinity, and prevents the
elements of bodies from freely uniting, we call vital.” But in a note
to the allegory above mentioned, added to the third edition of the
Views of Nature in 1849, he says: “Reflection and prolonged study in
the departments of physiology and chemistry have deeply shaken my
earlier belief in peculiar so-called vital forces. In the year 1797, *
* * I already declared that I by no means regarded the existence of
these peculiar vital forces as established.” And again: “The
difficulty of satisfactorily referring the vital phenomena of the
organism to physical and chemical laws depends chiefly (and almost in
the same manner as the prediction of meteorological processes in the
atmosphere) on the complication of the phenomena, and on the great
number of the simultaneously acting forces as well as the conditions
of their activity.”
Footnote 3:
Compare HENRY BENCE JONES, Croonian Lectures on Matter and Force.
London, 1868, John Churchill & Sons.
Footnote 4:
Ib., Preface, p. vi.
Footnote 5:
RANKINE, W. J. M., Philosophical Magazine, Feb., 1853. Also Edinburgh
Philosophical Journal, July, 1855.
Footnote 6:
ARMSTRONG, Sir WM. In his address as President of the British
Association for the Advancement of Science. Rep. Brit. Assoc., 1863,
li.
Footnote 7:
GROVE, W. R., in 1842. Compare “Nature” i, 335, Jan. 27, 1870. Also
Appleton’s Journal, iii, 324, Mch. 19, 1870.
Footnote 8:
Id., in Preface to The Correlation of Physical Forces, 4th ed.
Reprinted in The Correlation and Conservation of Forces, edited by E.
L. Youmans, p. 7. New York, 1865, D. Appleton & Co.
Footnote 9:
Id., ib., Am. ed., p. 33 et seq.
Footnote 10:
JOULE, J. P., Philosophical Transactions, 1850, p. 61.
Footnote 11:
See American Journal of Science, II, xxxvii, 296, 1864.
Footnote 12:
The work (W) done by a moving body is commonly expressed by the
formula W = MV^2, in which M, or the mass of the body, is equal to
w/2g; _i.e._, to the weight divided by twice the intensity of gravity.
The work done by our cannon-ball then, would be (1 × (1100)^2)/(2 ×
64⅓) = 9,404·14 foot-tons. If, further, we assume the resisting body
to be of such a character as to bring the ball to rest in moving ¼ of
an inch, then the final pressure would be 9,404·14 × 12 × 4 =
451,398·7 tons. But since, “in the case of a perfectly elastic body,
or of a resistance proportional to the advance of the center of
gravity of the impinging body from the point at which contact first
takes place, the final pressure (provided the body struck is perfectly
rigid) is double what would occur were the stoppage to occur at the
end of a corresponding advance against a uniform resistance,” this
result must be multiplied by two; and we get (451,398·7 × 2) 902,797
tons as the crushing pressure of the ball under these conditions.
Note: The author’s thanks are due to his friends Pres. F. A. P.
Barnard and Mr. J. J. Skinner for suggestions on the relation of
impact to statical pressure.
Footnote 13:
The unit of impact being that given by a body weighing one pound and
moving one foot a second, the impact of such a body falling from a
hight of 772 feet—the velocity acquired being 222¼ feet per second
(=√(2sg))—would be 1 × (222¼)^2 = 49,408 units, the equivalent in
impact of one heat-unit. A cannon-ball weighing 1000 lbs. and moving
1100 feet a second would have an impact of (1100)^2 × 1000 =
1,210,000,000 units. Dividing this by 49,408, the quotient is 24489
heat units, the equivalent of the impact. The specific heat of iron
being ·1138, this amount of heat would raise the temperature of one
pound of iron 215.191° F. (24,489 × ·1138) or of 1000 pounds of iron
215° F. 24489 pounds of water heated one degree, is equal to 136½
pounds, or 17 gallons U. S., heated 180 degrees; _i.e._, from 32° to
212° F.
Footnote 14:
Assuming the density of the earth to be 5·5, its weight would be
6,500,000,000,000,000,000,000 tons, and its impact—by the formula
given above—would be 1,025,000,000,000,000,000,000,000,000,000
foot-tons. Making the same supposition as in the case of our
cannon-ball, the final pressure would be that here stated.
Footnote 15:
TYNDALL, J., Heat considered as a mode of Motion; Am. ed., p. 57, New
York, 1863.
Footnote 16:
RANKINE (The Steam-engine and other prime Movers, London, 1866,) gives
the efficiency of Steam-engines as from 1-15th to 1-20th of the heat
of the fuel.
ARMSTRONG, Sir WM., places this efficiency at 1-10th as the maximum.
In practice, the average result is only 1-30th. Rep. Brit. Assoc.,
1863, p. liv.
HELMHOLTZ, H. L. F., says: “The best expansive engines give back as
mechanical work only eighteen per cent. of the heat generated by the
fuel.” Interaction of Natural Forces, in Correlation and Conservation
of Forces, p. 227.
Footnote 17:
THOMSEN, JULIUS, Poggendorff’s Annalen, cxxv, 348. Also in abstract in
Am. J. Sci., II, xli, 396, May, 1866.
Footnote 18:
American Journal of Science, II, xli, 214, March, 1866.
Footnote 19:
In this calculation the annual evaporation from the ocean is assumed
to be about 9 feet. (See Dr. BUIST, quoted in Maury’s Phys. Geography
of the Sea, New York, 1861, p. 11.) Calling the water-area of our
globe 150,000,000 square miles, the total evaporation in tons per
minute, would be that here given. Inasmuch as 30,000 pounds raised
one-foot high is a horse-power, the number of horse-powers necessary
to raise this quantity of water 3½ miles in one minute is
2,757,000,000,000. This amount of energy is precisely that set free
again when this water falls as rain.
Footnote 20:
Compare ODLING, WM., Lectures on Animal Chemistry, London, 1866. “In
broad antagonism to the doctrines which only a few years back were
regarded as indisputable, we now find that the chemist, like the
plant, is capable of producing from carbonic acid and water a whole
host of organic bodies, and we see no reason to question his ultimate
ability to reproduce all animal and vegetable principles whatsoever.”
(p. 52.)
“Already hundreds of organic principles have been built up from their
constituent elements, and there is now no reason to doubt our
capability of producing all organic principles whatsoever in a similar
manner.” (p. 58.)
Dr. Odling is the successor of Faraday as Fullerian Professor of
Chemistry in the Royal Institution of Great Britain.
Footnote 21:
MARSHALL, JOHN, Outlines of Physiology, American edition, 1868, p.
916.
Footnote 22:
FRANKLAND, EDWARD, On the Source of Muscular Power, Proc. Roy. Inst.,
June 8, 1866; Am. J. Sci., II, xlii, 393, Nov. 1866.
Footnote 23:
LIEBIG, JUSTUS VON, Die organische Chemie in ihrer Anwendung auf
Physiologie und Pathologie, Braunschweig, 1842. Also in his Animal
Chemistry, edition of 1852 (Am. ed., p. 26), where he says “Every
motion increases the amount of organized tissue which undergoes
metamorphosis.”
Footnote 24:
Compare DRAPER, JOHN WM. Human Physiology.
PLAYFAIR, LYON, On the Food of Man in relation to his useful work,
Edinburgh, 1865. Proc. Roy. Inst., Apr. 28, 1865.
RANKE, Tetanus eine Physiologische Studie, Leipzig, 1865.
ODLING, _op. cit._
Footnote 25:
VOIT, E., Untersuchungen über den Einfluss des Kochsalzes, des
Kaffees, und der Muskelbewegungen auf den Stoffwechsel, Munich, 1860.
SMITH, E., Philosophical Transactions, 1861, 747.
FICK, A., and WISLICENUS, J., Phil. Mag., IV, xxxi, 485.
FRANKLAND, E., _loc. cit._
NOYES, T. R., American Journal Medical Sciences, Oct. 1867.
PARKES, E. A., Proceedings Royal Society, xv, 339; xvi, 44.
Footnote 26:
SMITH, EDWARD, Philosophical Transactions, 1859, 709.
Footnote 27:
Authorities differ as to the amount of energy converted by the
steam-engine. (See Note 16.) Compare MARSHALL, _op. cit._, p. 918.
“Whilst, therefore, in an engine one-twentieth part only of the fuel
consumed is utilized as mechanical power, one-fifth of the food
absorbed by man is so appropriated.”
Footnote 28:
HEIDENHAIN, Mechanische Leistung Wärmeentwickelung und Stoffumsatz bei
der Muskelthätigkeit, Breslau, 1864.
See also HAUGHTON, SAMUEL, On the Relation of Food to work, published
in “Medicine in Modern Times,” London, 1869, Macmillan & Co.
Footnote 29:
HEIDENHAIN, _op. cit._ Also by FICK, Untersuchungen über
Muskel-arbeit, Basel, 1867. Compare also “Nature,” i, 159, Dec. 9,
1869.
Footnote 30:
DU BOIS-REYMOND, EMIL, On the time required for the transmission of
volition and sensation through the nerves, Proc. Roy. Inst. Also in
Appendix to Bence Jones’s Croonian lectures.
Footnote 31:
MARSHALL, _op. cit._, p. 227.
Footnote 32:
MELLONI, Ann. Ch. Phys., xlviii, 198.
See also NOBILI, Bibl. Univ., xliv, 225, 1830; lvii, 1, 1834.
Footnote 33:
The apparatus employed is illustrated and fully described in
Brown-Sequard’s Archives de Physiologie, i, 498, June, 1868. By it the
1-4000th of a degree Centigrade may be indicated.
Footnote 34:
LOMBARD, J. S., New York Medical Journal, v, 198, June, 1867. [A part
of these facts were communicated to me directly by their discoverer.]
Footnote 35:
WOOD, L. H., On the influence of Mental activity on the Excretion of
Phosphoric acid by the Kidneys. Proceedings Connecticut Medical
Society for 1869, p. 197.
Footnote 36:
On this question of vital force, see LIEBIG, Animal Chemistry. “The
increase of mass in a plant is determined by the occurrence of a
decomposition which takes place in certain parts of the plant under
the influence of light and heat.”
“The modern science of Physiology has left the track of Aristotle. To
the eternal advantage of science, and to the benefit of mankind it no
longer invents a _horror vacui_, a _quinta essentia_, in order to
furnish credulous hearers with solutions and explanations of
phenomena, whose true connection with others, whose ultimate cause is
still unknown.”
“All the parts of the animal body are produced from a peculiar fluid
circulating in its organism, by virtue of an influence residing in
every cell, in every organ, or part of an organ.”
“Physiology has sufficiently decisive grounds for the opinion that
every motion, every manifestation of force, is the result of a
transformation of the structure or of its substance; that every
conception, every mental affection, is followed by changes in the
chemical nature of the secreted fluids; that every thought, every
sensation is accompanied by a change in the composition of the
substance of the brain.”
“All vital activity arises from the mutual action of the oxygen of the
atmosphere and the elements of the food.”
“As, in the closed galvanic circuit, in consequence of certain changes
which an inorganic body, a metal, undergoes when placed in contact
with an acid, a certain something becomes cognizable by our senses,
which we call a current of electricity; so in the animal body, in
consequence of transformations and changes undergone by matter
previously constituting a part of the organism, certain phenomena of
motion and activity are perceived, and these we call life, or
vitality.”
“In the animal body we recognize as the ultimate cause of all force
only one cause, the chemical action which the elements of the food and
the oxygen of the air mutually exercise on each other. The only known
ultimate cause of vital force, either in animals or in plants, is a
chemical process.”
“If we consider the force which determines the vital phenomena as a
property of certain substances, this view leads of itself to a new and
more rigorous consideration of certain singular phenomena, which these
very substances exhibit, in circumstances in which they no longer make
a part of living organisms.”
Also OWEN, RICHARD, (Derivative Hypothesis of Life and Species,
forming the 40th chapter of his Anatomy of Vertebrates, republished in
Am. J. Sci., II, xlvii, 33, Jan. 1869.) “In the endeavor to clearly
comprehend and explain the functions of the combination of forces
called ‘brain,’ the physiologist is hindered and troubled by the views
of the nature of those cerebral forces which the needs of dogmatic
theology have imposed on mankind.” * *
“Religion pure and undefiled, can best answer how far it is righteous
or just to charge a neighbor with being unsound in his principles who
holds the term ‘life’ to be a sound expressing the sum of living
phenomena; and who maintains these phenomena to be modes of force into
which other forms of force have passed, from potential to active
states, and reciprocally, through the agency of these sums or
combinations of forces impressing the mind with the ideas signified by
the terms ‘monad,’ ‘moss,’ ‘plant,’ or ‘animal.’”
And HUXLEY, THOS. H., “On the Physical Basis of Life,” University
Series, No. 1. College Courant, 1870.
_Per contra_, see the Address of Dr. F. A. P. Barnard, as retiring
President, before the Am. Assoc. for the Advancement of Science,
Chicago meeting, August, 1868. “Thought cannot be a physical force,
because thought admits of no measure.”
GOULD, BENJ. APTHORP, Address as retiring President, before the
American Association at its Salem meeting, Aug., 1869.
BEALE, LIONEL S., “Protoplasm, or Life, Matter, and Mind.” London,
1870. John Churchill & Sons.
Footnote 37: