views and measurements of two other skulls of men of known intellectual
capacity. One of these is Johan Jacob Wilhelm Heinse, the author of
_Ardinghello_, a work of high character in the elements of æsthetic
criticism, though as a romance fit to rank with _Don Juan_ in subjective
significance and morality. He wrote another romance entitled
_Hildegard_; in addition to numerous articles and translations of
Petronius, Tasso, etc., which won for him the high commendation of
Goethe, and the more guarded admiration of Wieland. His skull, as
figured by Dr. Lucae, shows the frontal suture still open at the age of
fifty-three, at which he died. The internal capacity of the skull is
stated as 41.4 oz., equivalent to 1173 grms. In this, as in other
examples hereafter referred to, Dr. Lucae has gauged the capacity of the
skull with peas, and gives the weight in “unzen.” In the results deduced
from them here the _unzen_ are assumed to be Prussian ounces, the lb. of
12 oz. equal to 350.78348 grms. As already noted, the determination of
the internal capacity of the skull by varying tests, such as pease,
rice, and sands of diverse degrees of fineness, leads to uncertain
results. In those here deduced from the data furnished by Dr. Lucae, the
unzen have been tested by a series of experiments made with a view to
correct the error necessarily resulting from the fact that peas do not
entirely fill the cavity. The results show that 82.5 grms. of ordinary
sized peas occupy the space of 100 grms. of water. Deducting 10 per cent
for membranes and fluids, the estimated brain-weight of Heinse is 1379
grms. or 48.7 oz. av. The dimensions of the skull are given thus:—
───────────────┬──────────┬──────────┬──────────
│ │ │
│ Height. │ Length. │ Breadth.
│ │ │
───────────────┼──────────┼──────────┼──────────
│ │ │
Fore part │ 4.9 │ 4.00 │ 4.1
Middle part │ 4.1 │ 3.11 │ 5.3
Hind part │ 3.9 │ 3.60 │ 4.1
│ │ │
───────────────┴──────────┴──────────┴──────────
The other example produced by Dr. Lucae is that of Dr. Christian
Heinrich Bünger, Professor of Anatomy in the University of Marburg. In
this skull the frontal suture is still more strongly defined at the age
of sixty than in that of Heinse. The internal capacity of the skull is
stated as 42.8 oz., equivalent to 1213 grms., which, dealt with as above
stated, yields 1410 grms. or 49.8 oz. av. Other dimensions of the skull
are given as follows:—
───────────────┬──────────┬──────────┬──────────
│ │ │
│ Height. │ Length. │ Breadth.
│ │ │
───────────────┼──────────┼──────────┼──────────
│ │ │
Fore part │ 4.8 │ 4.1 │ 4.2
Middle part │ 4.9 │ 4.1 │ 5.0
Hind part │ 3.7 │ 3.1 │ 4.1
│ │ │
───────────────┴──────────┴──────────┴──────────
The premature ossification of the sagittal suture, by arresting the
expansion of the brain laterally, is a frequent source of abnormal
elongation of the head. On the other hand the frontal suture, which
ordinarily closes in the man-child before birth, though persistent in
the lower animals, is occasionally found to remain open in man till
maturity, as in the two notable cases here described. Darwin refers to
it as a case of arrested development. “This suture,” he says,
“occasionally persists, more or less distinctly, in man after maturity,
and more frequently in ancient than in recent crania; especially, as
Canestrini has observed, in those exhumed from the Drift, and belonging
to the brachycephalic type. In this and other instances the cause of
ancient races approaching the lower animals in certain characters more
frequently than do the modern races, appears to be that the latter stand
at a somewhat greater distance in the long line of descent from their
early semi-human progenitors.”[173] It may be permissible to express a
doubt as to this relative frequency of the occurrence of the frontal
suture in ancient and modern races, since the great naturalist does not
state it as a result of his own observations. Not only am I led to do so
from repeatedly noting its occurrence in modern crania; but its effect
can in no way favour arrested development. It must rather admit of the
free expansion of the frontal lobes of the brain, the decrease of which
in a progressive ratio is characteristic of the orang, chimpanzee, and
baboon.
On the general question of cranial development as an index of cerebral
capacity, Professor Welcker assigns a standard, which was accepted by
Dr. Thurnam, thus: “Skulls of more than 540 to 550 millimetres in
horizontal circumference (the weight of brain belonging to which is 1490
to 1560 grms., or 52.5-55 oz. av.), are to be regarded as exceptionally
large. The designation of _kephalones_, proposed by Virchow, might
commence from this point. Men with great mental endowments fall, for the
most part, under the definition of kephalony. If we consider the
relations of capacity, 1800 grms. (63.5 oz.) appears to be the greatest
attainable weight of brain within a skull not pathologically enlarged.”
But the brain of Cuvier—the heaviest healthy brain yet
recorded,—exceeded this. Its weight is stated by Wagner as 1861 grms.,
or 65.8 oz.; but this M. Broca corrects to 1829.96 grms. Even thus
reduced it exceeds the limits assigned by Professor Welcker to the
normal healthy brain. But a curious commentary upon this is furnished by
the fact that the modern English skull which Dr. Davis selects as
presenting the most striking analogy to the Neanderthal skull—“the most
ape-like skull which Professor Huxley had ever beheld,”—though marked
not only by the prominence of the superciliary ridges, but by great
depression of the frontal region, appears to have a cubical capacity
equivalent to that of Dr. Abercrombie, whose brain is only surpassed by
that of Cuvier among the ascertained brain-weights of distinguished
men.[174] Its capacity is 94 oz. of sand, or 113 cubic inches,
equivalent—after making the requisite deduction for membranes and
fluids,—to a brain-weight of 63 oz.
I have attempted in the following table to reduce to some common
standard such imperfect glimpses as are recoverable of the cranial
capacity of some distinguished men, of whose actual brain-weights no
record exists:—
TABLE III
CRANIAL CAPACITY OF DISTINGUISHED MEN
────────────────────┬────────┬──────────┬───────────────┬───────────────
│ │ │ │
│Length. │ Breadth. │Circumference. │ Estimated
│ │ │ │ Brain-Weight.
│ │ │ │
────────────────────┼────────┼──────────┼───────────────┼───────────────
│ │ │ │
Dante │ — │ — │ — │ 51.3
Robert the Bruce │ 7.70 │ 6.25 │ 22.25 │ —
Burns │ 8.00 │ 5.95 │ 22.25 │ —
Scott (head) │ 9.00 │ 6.40 │ 23.10 │ —
Heinse │ — │ 5.30 │ — │ 48.0
Bünger │ — │ 5.00 │ — │ 49.8
Ugo Foscolo │ 6.90 │ 5.70 │ 20.50 │ 48.4
│ │ │ │
────────────────────┴────────┴──────────┴───────────────┴───────────────
Some of the examples adduced in the above table appear to exhibit
instances of mental endowment of high character, without the
corresponding degree of cranial, and consequently cerebral development.
The following table exhibits recorded examples of a series of actual
brain-weights of distinguished men. It seems to lend confirmation to the
idea that great manifestation of mental endowment is correlated, in the
majority of observed cases, to a brain above the normal average in mass
or weight. But even here intellect and brain-weight are not strictly in
uniform ratio. Several of the following brain-weights, including that of
Tiedemann, are furnished by Wagner, in the _Vorstudien des Menschlichen
Gehirns_; but in an elaborate table of brain-weights given in the
_Morphologie und physiologie des Menschlichen gehirns als Seelenorgan_,
the brain of Byron is classed above all except Cuvier; while Vogt gives
the same place, by estimate, to Schiller’s, as next in rank to that of
the great naturalist among highly developed brains. Dr. Thurnam states
his authorities for others, when producing them in his valuable
contribution to the _Journal of Mental Science_ “On the Weight of the
Brain.” For that of Webster he refers to “the unsatisfactory article on
the brain of Daniel Webster, _Edin. Med. Surg. Journ._, vol. lxxix. p.
355.” Dr. J. C. Nott, in his “Comparative Anatomy of Races” (_Types of
Mankind_, p. 453), says: “Dr. Wyman, in his _post-mortem_ examination of
the famed Daniel Webster, found the internal capacity of the cranium to
be 122 cubic inches, and in a private letter to me, he says: ‘The
circumference was measured outside of the integuments before the scalp
was removed, and may, perhaps, as there was much emaciation, be a little
less than in health.’ It was 23¾ inches in circumference; and the Doctor
states that it is well known there are several heads in Boston larger
than Webster’s. I have myself, in the last few weeks, measured half a
dozen heads as large and larger.” The circumference, it will be seen,
exceeds the corresponding measurement of Scott’s head, taken under
similar circumstances. But the statement of 122 cubic inches as the
internal capacity of Webster’s skull seems open to question. If correct,
instead of 53.5 oz. of brain-weight as stated in the following table, it
is the equivalent of a brain-weight of fully 65 oz., or one in excess
even of that, of Cuvier. The brain-weights of Goodsir, Simpson, and
Agassiz, are given in the following table from the reported autopsy in
each case:—
TABLE IV
BRAIN-WEIGHTS OF DISTINGUISHED MEN
─────┬────────────────────┬─────────────────────────┬──────┬──────┬──────
│ │ │ │ │
│ │ │ Age. │Oz. │Grms.
│ │ │ │ │
─────┼────────────────────┼─────────────────────────┼──────┼──────┼──────
│ │ │ │ │
1│Cuvier │Naturalist │ 63 │64.5 │ 1830
2│Byron │Poet │ 36 │63.5? │ 1799
3│Abercrombie │Philosopher, Physician │ 64 │63. │ 1785
4│Schiller │Poet │ 46 │63.? │ 1785
5│Goodsir │Anatomist │ 53 │57.55 │ 1629
6│George Brown │Statesman (Canadian) │ 61 │56.3 │ 1595
7│Harrison │Chief Justice │ 45 │56. │ 1586
8│Spurzheim │Phrenologist, Physician │ 56 │55.06 │ 1575
9│Simpson │Physician, Archæologist │ 59 │54. │ 1530
10│Dirichlet │Mathematician │ 54 │53.6 │ 1520
11│De Morny │Statesman │ 50 │53.6 │ 1520
12│Napoleon I. │General, Statesman │ 52 │53.5 │ 1516
13│Daniel Webster │Statesman │ 70 │53.5 │ 1516
14│Campbell │Lord Chancellor │ 80 │53.5 │ 1516
15│Agassiz │Naturalist │ 66 │53.4 │ 1512
16│Chalmers │Author, Preacher │ 67 │53. │ 1502
17│Fuchs │Pathologist │ 52 │52.9 │ 1499
18│De Morgan │Mathematician │ 73 │52.7 │ 1493
19│Gauss │Mathematician │ 78 │52.6 │ 1492
20│Broca │Anthropologist │ — │52.5 │ 1488
21│Dupuytren │Surgeon │ 58 │50.7 │ 1436
22│Grote │Historian │ 76 │49.75 │ 1410
23│Whewell │Philosopher │ 71 │49. │ 1390
24│Hermann │Philologist │ 51 │47.9 │ 1358
25│Tiedemann │Physiologist │ 80 │44.2 │ 1254
26│Hausmann │Mineralogist │ 77 │43.2 │ 1226
│ │ │ │ │
─────┴────────────────────┴─────────────────────────┴──────┴──────┴──────
Dr. Thurnam, in producing fifteen of the above examples, remarks:
“Altogether, they decidedly confirm the generally received view of the
connection between size of brain and mental power and intelligence”; and
he adds his conviction that if the examination of the brain in the upper
ranks of society, and in men whose mental endowments are well known,
were more generally available, further confirmation would be given to
this conclusion. The converse, at least, is certain, that no great
intelligence or unwonted mental power is possible with a brain much
below the average in mass and weight But while the above list exhibits a
series of exceptionally high brain-weights of distinguished men, the
relative weights in some cases—as in Napoleon—are calculated to excite
surprise if viewed as an index of comparative intellectual capacity. On
the other hand, those lowest in the scale, and below the mean weight,
include men of undoubted eminence in letters and science; while the
proofs are no less unquestionable that a large healthy brain is not
invariably the organ of unwonted intelligence or mental activity.
In the _Philosophical Transactions_ of 1861, Dr. Boyd published an
elaborate series of researches illustrative of the weight of various
organs of the human body, including the weights of two thousand brains.
Most of the healthy brains are those of patients in the St. Marylebone
Infirmary, and have already been referred to as necessarily representing
the indigent and uneducated classes of London. Here, therefore, if an
unusually large brain is the index of intellectual power, every
probability was against the occurrence of brains above the average size
or weight. But the results by no means confirm this assumption. Among
the patients in the Edinburgh Royal Infirmary, in like manner, though
including the better class of artizans and others from country
districts, we might still look for a confirmation of M. Broca’s
assumption, based on extensive observations of French crania, “that,
other things being equal, whether as the result of education, or by
hereditary transmission, the volume of the skull, and consequently of
the brain, is greater in the higher than in the lower classes.” But Dr.
Peacock’s tables include four brain-weights, three of them of a sailor,
a printer, and a tailor, respectively, ranging from 61 to 62.75 oz.; and
so surpassing all but two, or at the most three, of the heaviest
ascertained brain-weights of distinguished men. Tried by the posthumous
test of internal capacity, three skulls of nameless Frenchmen, derived
from the common cemeteries of Paris, in like manner showed brains
equalling in size that of Cuvier. The following are the maximum
brain-weights among the St. Marylebone patients apparently unaffected by
cerebral disease:—
TABLE V
MAXIMUM BRAIN-WEIGHTS—ST. MARYLEBONE
───────────────┰─────────────────────┰─────────────────────
┃ ┃
AGE. ┃ MALE. ┃ FEMALE.
┃ Oz. Grms. ┃ Oz. Grms.
┃ ┃
───────────────╂─────────────────────╂─────────────────────
┃ ┃
7-14 ┃ 57.25 1622 ┃ 52.00 1473
14-20 ┃ 58.50 1658 ┃ 52.00 1473
20-30 ┃ 57.00 1615 ┃ 55.25 1565
30-40 ┃ 60.75 1721 ┃ 53.00 1502
40-50 ┃ 60.00 1700 ┃ 52.50 1488
50-60 ┃ 59.00 1672 ┃ 52.50 1488
60-70 ┃ 59.50 1686 ┃ 54.00 1530
70-80 ┃ 55.25 1565 ┃ 49.50 1403
80 ┃ 53.75 1523 ┃ 48.00 1360
All Ages. ┃ ┃
7-80 ┃ 60.75 1721 ┃ 55.25 1565
┃ ┃
───────────────┸─────────────────────┸─────────────────────
The stature, or relative size of body, has already been referred to as
an element in testing the comparative male and female weight of brain;
and it is one which ought not to be overlooked in estimating the
comparative size and weight of the brains of distinguished men. From my
own recollections of Dr. Chalmers, who was of moderate stature, his head
appeared proportionally large. The same was noticeable in the cases of
Lord Jeffrey, Lord Macaulay, Sir James Y. Simpson, and very markedly so
in that of De Quincey. The philosopher Kant was also of small stature;
and Dr. Thurnam refers to the observation of Carus that he had a head
not absolutely large, though, in proportion to the small and puny body
of that eminent thinker, it was of remarkable size. Among the
large-brained artizans of the Marylebone Infirmary, on the contrary, the
probabilities are in favour of a majority of them being men of full
muscular development and ample stature. Nevertheless, with every
allowance for this, it still remains probable, if not demonstrable, that
from the same humble and unnoted class, examples of megalocephaly could
be selected little short in cerebral mass, and apparently in
brain-weight, of the group of men whose large brains are recognised as
the concomitants of exceptionally great mental capacity and intellectual
vigour. Unless, therefore, we are contented to accept the poet’s dictum,
“Their lot forbad,”[175] and assume that “chill penury repressed their
noble rage, and froze the genial current of the soul,” it is manifest
that other elements besides those of volume or weight are essential as
cerebral indices of mental power. Dr. Thurnam, after noting examples
that had come under his own notice of brain-weights above the
medium—but which, as those of insane patients, may be assigned to other
causes than healthy cerebral development,—adds: “The heaviest brain
weighed by me (62 oz., or 1760 grms.) was that of an uneducated butcher,
who was just able to read, and who died suddenly of epilepsy, combined
with mania, after about a year’s illness. The head was large, but
well-formed; the brain of normal consistence; the _puncta vasculosa_
numerous.” In cases like this, of weighty brain with no corresponding
manifestation of intellectual power, something else was wanting besides
an ampler sphere. The mere position of a humble artizan or labourer will
not suffice to mar the capacity to “make by force his merit known,”
which pertains to the “divinely gifted man.”
Arkwright, Franklin, Watt, Stephenson, Farraday, Hugh Miller, and others
of the like type of self-made men, are not rare. Among the large-brained
artizans, scarcely one can have had a more limited sphere for the
exercise of mental vigour than the poet Burns, the child of poverty and
toil, who refers to his own early years as passed in “the unceasing moil
of a galley-slave.” In his case the very means essential to a healthy
physical development were stinted at the most critical period of life.
His brother Gilbert says: “We lived sparingly. For several years
butcher’s meat was a stranger to the house; while all exerted themselves
to the utmost of their strength, and rather beyond it, in the labours of
the farm. My brother, at the age of thirteen, assisted in thrashing the
crop of corn, and at fifteen was the principal labourer on the farm.”
Such premature toil and privations left their permanent stamp on his
frame. “Externally, the consequences appeared in a stoop of the
shoulders, which never left him; but internally, in the more serious
form of mental depression, attended by a nervous disorder which affected
the movements of the heart.” He had only exchanged the toil on his
father’s farm for equally unremitting labour on his own, when the finest
of his poems were written; nor would it be inconsistent with all the
facts to assume that the privations of his early life diminished his
capacity for continuous mental activity; as it undoubtedly impaired his
physical constitution. But, while the possession of a brain much above
the average in size might have seemed to account for his triumph over
the depressing influences of his limited sphere, the fact that his brain
appears to have been below the average size, points to some other
requisite than mere cerebral mass as essential to intellectual vigour.
The brain is influenced in all its functions by the character and the
amount of blood circulating through it, and promptly manifests the
effects of any deleterious substance, such as alcohol or opium,
introduced into its tissues. It depends, like other portions of the
nervous system, on an adequate supply of nourishment. In both respects
the brain of the Ayrshire poet was injuriously affected, in so far as we
may infer from all the known circumstances of his life.
The human brain is large in proportion to the body in infancy and youth;
and the opinions of leading anatomists and physiologists early in the
present century favoured the idea that it attained its full size within
a few years after birth. Professor Sœmmering assumed this to take place
so early as the third year. Sir William Hamilton explicitly stated his
conclusion thus: “In man the encephalon reaches its full size about
seven years of age”; and Tiedemann assigns the eighth year as that in
which it attains its greatest development. But the more accurate and
extended observations since carried on rather tend to the conclusion
that the brain not only goes on increasing in size and weight to a much
later period of life; but that it is healthfully stimulated by habitual
activity, and under exceptionally favouring circumstances it may
increase in weight long after the body has attained its maximum.
The largest average brain-weights, as determined by observations on the
brains of upwards of 2000 men and women in different countries of
Europe, have indeed been found in those not above twenty years of age;
and from a nearly equal number of English examples, Dr. Boyd determines
the period of greatest average weight to be the interval between
fourteen and twenty years of age; but this includes cases in which death
has ensued from undue or premature brain development.
Other evidence leaves no room for doubt that cases are not rare of the
growth, or increased density of the brain up to middle age; while the
observations of Professor Welcker indicate this process extended to a
later period of life. The average brain-weights, as given by Boyd,
Peacock, and Broca, from healthy or sane cases, along with those of
Welcker, include the weights of 47 male brains from ten to twenty years
of age, giving an average of 49.6 oz., or 1405 grms.; and of 112 male
brains from twenty to thirty years of age, giving an average of 48.9
oz., or 1384 grms.; and the results of a nearly equal number of female
brains closely approximate. They embrace English, Scotch, German, and
French, men and women. Dr. Welcker’s results indicate the period of
maximum brain-weight to be between 30-40, as shown in the following
table:—
TABLE VI
AVERAGE WEIGHT OF THE BRAIN AT DIFFERENT AGES
───────────────┰─────────────────────┰─────────────────────
┃ ┃
AGE. ┃ MALE. ┃ FEMALE.
┃ Oz. Av. Grms. ┃ Oz. Av. Grms.
┃ ┃
───────────────╂─────────────────────╂─────────────────────
┃ ┃
From 10-20 ┃ 47.5 1346 ┃ 43.1 1221
20-30 ┃ 49.5 1404 ┃ 44.1 1251
30-40 ┃ 49.5 1404 ┃ 44.8 1272
40-50 ┃ 48.6 1379 ┃ 43.5 1234
50-60 ┃ 48.1 1365 ┃ 43.5 1234
60-70 ┃ 46.1 1306 ┃ 42.8 1213
┃ ┃
───────────────┸─────────────────────┸─────────────────────
In the female examples, amounting to thirty-one between seventy and
eighty years of age, and six between eighty and ninety, the continuous
diminution of brain-weight corresponds with the increasing age; but in
the male examples, sixty-five cases between sixty and seventy years of
age yield an average brain-weight of 46.1 oz., while twenty-seven cases
between seventy and eighty years of age give 47.9 as the average;
falling in the next decade to 43.8.
It may be inferred from the number of cases pointing to an early
attainment of the highest average brain-weight, not that the brain
differs from all other internal organs of the human body in attaining
its maximum before the period of puberty; but that physical as well as
mental vigour are dependent on the maintenance of a nice equilibrium
between the brain and the other organs while in process of development.
The observations of Dr. Boyd, including the results of 2614
_post-mortem_ examinations of sane and insane patients of all ages,
showed that the average weight of the brain of “still-born” children at
the full period was much greater than that of the new-born living child.
It is a legitimate inference, therefore, that death in the former cases
was traceable to an excessive premature development of the brain. Again,
when it is shown from numerous cases that the highest average weights of
brain in both sexes occur not later than twenty years of age, it appears
a more legitimate inference to trace to exceptional cerebral development
towards the period of adolescence, the mortality which rendered
available so many examples of unusually large or heavy brains, than to
assume that the normal healthy brain begins to diminish at that age.
It is a fact familiar to popular observation that a large head in youth
is apt to be unfavourable to life. A tendency to epilepsy appears to be
the frequent concomitant of an unusually large brain; and with the
congestion accompanying its abnormal condition, this may account for the
weights of such diseased brains as have been repeatedly found in excess
of nearly all the recorded examples of megalocephaly in the cases of
distinguished men. But a greater interest attaches to a remarkable
example of healthy megalocephaly recorded in the _British Medical
Journal_ for 1872. The case was that of a boy thirteen years of age, who
died in Middlesex Hospital from injuries caused by a fall from an
omnibus. His brain was found to weigh 58 oz. He had been a particularly
healthy lad, without any evidence of rachitis, and very intelligent.
This is a strikingly exceptional case of a healthy brain, at the age of
thirteen, exceeding in weight all but two of the greatest ascertained
brain-weights of distinguished men.
From the evidence already adduced of relative cubical capacity of the
skulls of different races, it appears, as was to be expected, that there
is a greater prevalence of the amply-developed brain among the higher
and more civilised races. But all averages are apt to be deceptive; and
the progressive scale from the smallest up to the greatest mass of brain
is by no means in the precise ratio of an intellectual scale of
progression. The results of Dr. J. B. Davis’s investigations, based on
the study of a large, and in many cases a seemingly adequate number of
skulls, bring out this remarkable fact, that, so far from the
Polynesians occupying a rank in the lowest scale, as affirmed by
Professor Vogt, the Oceanic races of the Pacific generally rank in
internal capacity of skull, and consequent size of brain, next to the
European.