David Humphreys in a letter to Sir Joseph Banks, published in the
_Philosophical Transactions_ for 1813, has been thus abridged by
Huxley:--'It appears that one Seth Wright, the proprietor of a farm on
the banks of the Charles River, in Massachusetts, possessed a flock
of fifteen ewes and a ram of the ordinary kind. In the year 1791 one
of the ewes presented her owner with a male lamb differing, for no
assignable reason, from its parents by a disproportionately long body
and short bandy legs; whence it was unable to emulate its relatives in
those sportive leaps over the neighbours' fences in which they were
in the habit of indulging, much to the good farmer's vexation. With
the "cuteness" characteristic of their nation, the neighbours of the
Massachusetts farmer imagined it would be an excellent thing if all
his sheep were imbued with the stay-at-home tendencies enforced by
Nature upon the newly-arrived ram; and they advised Wright to kill
the old patriarch of his fold and instal the new Ancon ram in his
place. The result justified their sagacious anticipations.... The
young lambs were almost always either pure Ancons or pure ordinary
sheep. But when sufficient Ancon sheep were obtained to interbreed
with one another, it was found that the offspring were always pure
Ancon. Colonel Humphreys, in fact, states that he was acquainted with
only "one questionable case of a contrary nature." By taking care to
select Ancons of both sexes for breeding from, it thus became easy to
establish an exceedingly well-marked race--so peculiar that even when
herded with other sheep, it was noted that the Ancons kept together.
And there is every reason to believe that the existence of this breed
might have been indefinitely protracted: but the introduction of the
Merino sheep--which were not only very superior to the Ancons in wool
and meat, but quite as quiet and orderly--led to the complete neglect
of the new breed, so that in 1813 Colonel Humphreys found it difficult
to obtain the specimen whose skeleton was presented to Sir Joseph
Banks. We believe that for many years no remnant of it has existed in
the United States.'
It is easy, as Huxley remarks, to understand why, whereas Gratio
Kelleia did not become the ancestor of a race of six-figured and
six-toed men, Seth Wright's Ancon ram became a nation of long-bodied,
short-legged sheep. If the purely hexadactylic descendants of Gratio
Kelleia, and all the purely hexadactylic members of the Colburn family,
in the third and fourth generations, had migrated to some desert
island, and had been careful not only to exclude all visitors having
the normal number of fingers and toes, but to send away before the
age of puberty all children of their own which might depart in any
degree from the pure hexadactylic type, there can be no doubt that
under favourable conditions the colony would have become a nation
of six-fingered folk. Among such a nation the duodecimal system
of notation would flourish, and some remarkable performers on the
pianoforte, flute, and other instruments, might be looked for; but we
do not know that they would possess any other advantage over their
pentadactylic contemporaries. Seeing that the system of colonising
above described is antecedently unlikely, and that no special advantage
could be derived from the persistence of any hitherto known abnormal
variety of the human race, it is unlikely that for many generations
yet to come we shall hear of six-fingered, hairy-faced, horny-skinned,
or hare-lipped nations. The only peculiarities which have any chance
of becoming permanent are such as, while not very uncommon, stand
in the way of intermarriage with persons not similarly affected.
A similar remark, as will presently appear, applies to mental and
moral characteristics. The law according to which contrast is found
attractive and similitude repugnant, though wide in its range, is not
universal; and there are cases in which resemblance, if it has not
the charm found (under ordinary circumstances) in contrast, is yet a
necessary element in matrimonial alliances.
The inheritance of constitutional traits comes next to be considered.
It is probably not less frequently observed, and is in several respects
more interesting than the inheritance of peculiarities of bodily
configuration.
Longevity, which may be regarded as measuring the aggregate
constitutional energy, is well known to be hereditary in certain
families, as is short duration of life in other families. The best
proof that this is the case is found in the action of insurance
companies, in ascertaining through their agents the longevity of the
ancestors of persons proposing to insure their lives. Instances of
longevity during several successive generations are too common to
be worth citing. Cases in which, for generation after generation, a
certain age, far short of the threescore years and ten, has not been
passed, even when all the circumstances have favoured longevity, are
more interesting. One of the most curious among these is the case of
the Turgot family, in which the age of fifty-nine had not been for
generations exceeded, to the time when Turgot made the name famous.
At the age of fifty, when he was in excellent health, and apparently
had promise of many years of life, he expressed to his friends his
conviction that the end of his life was near at hand. From that time
forward he held himself prepared for death, and, as we know, he died
before he had completed his fifty-fourth year.
Fecundity is associated sometimes with longevity, but in other cases it
is as significantly associated with short duration of life. Of families
in which many children are born but few survive, we naturally have
less striking evidence than we have of families in which many children
of strong constitutions are born for several successive generations.
What may be called the fecundity of the short-lived is a quality
commonly leading in no long time to the disappearance of the family
in which it makes its appearance. It is the reverse, of course, with
fecundity in families whose members show individually great vigour of
constitution and high vital power. Ribot mentions several cases of this
sort among the families of the old French _noblesse_. Thus Anne de
Montmorency--who, despite his feminine name, was certainly by no means
feminine in character (at the Battle of St. Denis, in his sixty-sixth
year, he smashed with his sword the teeth of the Scotch soldier who was
giving him his death-blow) was the father of twelve children. Three of
his ancestors, Matthew I., Matthew II., and Matthew III., had, in all,
eighteen children, of whom fifteen were boys. 'The son and grandson of
the great Condé had nineteen between them, and their great-grandfather,
who lost his life at Jarnac, had ten. The first four Guises reckoned
in all forty-three children, of whom thirty were boys. Achille de
Harley had nine children, his father ten, and his great-grandfather
eighteen.' In the family of the Herschels in Hanover and in England, a
similar fecundity has been shown in two generations out of three. Sir
W. Herschel was one of a family of twelve children, of whom five were
sons. He himself did not marry till his fiftieth year, and had only one
son. But Sir John Herschel was the father of eleven children.
Of constitutional peculiarities those affecting the nervous system
are most frequently transmitted. We do not, however, consider them
at this point, because they are viewed ordinarily rather as they
relate to mental and moral characteristics than as affections of
the body. The bodily affections most commonly transmitted are those
depending on what is called diathesis--a general state or disposition
of the constitution predisposing to some special disease. Such are
scrofula, cancer, tubercular consumption, gout, arthritis, and some
diseases specially affecting the skin. It would not be desirable to
discuss here this particular part of our subject, interesting though
it undoubtedly is. But it may be worth while to note that we have,
in the variety of forms in which the same constitutional bad quality
may present itself, evidence that what is actually transmitted is not
a peculiarity affecting a particular organ, even though in several
successive generations the disease may show itself in the same part of
the body, but an affection of the constitution generally. We have here
an answer to the question asked by Montaigne in the essay from which
we have already quoted. The essay was written soon after he had for
the first time experienced the pangs of renal calculus:--''Tis to be
believed,' he says, 'that I derived this infirmity from my father, for
he died wonderfully tormented' with it; he was 'never sensible of his
disease till the sixty-seventh year of his age, and before that had
never felt any grudging or symptom of it' ... 'but lived till then in
a happy vigorous state of health, little subject to infirmities, and
continued seven years after in this disease, and dyed a very painful
death. I was born about twenty-five years before his disease seized
him, and in the time of his most flourishing and healthful state of
body, his third child in order of birth: where could his propension
to this malady lie lurking all that while? And he being so far from
the infirmity, how could that small part of his substance carry away
so great an impression of its share? And how so concealed that, till
five-and-forty years after, I did not begin to be sensible of it? being
the only one to this hour, amongst so many brothers and sisters, and
all of one mother, that was ever troubled with it. He that can satisfie
me in this point, I will believe him in as many other miracles as he
pleases, always provided that, as their manner is, he does not give me
a doctrine much more intricate and fantastic than the thing itself, for
current pay.' When we note, however, that in many cases the children
of persons affected like the elder Montaigne are not affected like
the parents, but with other infirmities, as the tendency to gout,
and _vice versâ_ (a circumstance of which I myself have but too good
reason to be cognisant, a parent's tendency to gout having in my case
been transmitted in the modified but even more troublesome form of
the disease which occasioned Montaigne so much anguish), we perceive
that it is not 'some small part of the substance' which transmits its
condition to the child, but the general state of the constitution.
Moreover, it may be hoped in many cases (which would scarcely be the
case if the condition or qualities of some part of the body only were
transmitted) that the germs of disease, or rather the predisposition
to disease, may be greatly diminished, or even entirely eradicated, by
suitable precautions. Thus persons inheriting a tendency to consumption
have become, in many cases, vigorous and healthy by passing as much
of their time as possible in the open air, by avoiding crowded and
over-heated rooms, taking moderate but regular exercise, judicious
diet, and so forth. We believe that the disease which troubled the
last fifteen years of the life of Montaigne might readily have been
prevented, and the tendency to it eradicated, during his youth.
Let us turn, however, from these considerations to others more
interesting, though less important, and on the whole perhaps better
suited to these pages.
The inheritance of tricks or habits is one of the most perplexing
of all the phenomena of heredity. The less striking the habit, the
more remarkable, perhaps, is its persistence as an inherited trait.
Giron de Buzareingues states that he knew a man who, when he lay on
his back, was wont to throw his right leg across the left; one of
this person's daughters had the same habit from her birth, constantly
assuming that position in the cradle, notwithstanding the resistance
offered by the swaddling bands.[17] Darwin mentions another case in
his _Variation of Animals and Plants under Domestication_:--A child
had the odd habit of setting its fingers in rapid motion whenever it
was particularly pleased with anything. When greatly excited, the same
child would raise the hand on both sides as high as the eyes, with the
fingers in rapid motion as before. Even in old age he experienced a
difficulty in refraining from these gestures. He had eight children,
one of whom, a little girl, when four years of age, used to set her
fingers going, and to lift up her hands after the manner of her father.
A still more remarkable case is described by Galton. A gentleman's wife
noticed that when he lay fast asleep on his back in bed he had the
curious trick of raising his right arm slowly in front of his face,
up to his forehead, and then dropping it with a jerk, so that the
wrist fell heavily on the bridge of his nose. The trick did not occur
every night, but occasionally, and was independent of any ascertained
cause. Sometimes it was repeated incessantly for an hour or more. The
gentleman's nose was prominent, and its bridge often became sore from
blows which it received. At one time an awkward sore was produced
that was long in healing, on account of the recurrence, night after
night, of the blows which first caused it. His wife had to remove the
button from the wrist of his night-gown, as it made severe scratches,
and some means were attempted of tying his arm. Many years after
his death, his son married a lady who had never heard of the family
incident. She, however, observed precisely the same peculiarity in her
husband; but his nose, from not being particularly prominent, has never
as yet suffered from the blows. The trick does not occur when he is
half asleep, as, for example, when he is dozing in his arm-chair; but
the moment he is fast asleep, he is apt to begin. It is, as with his
father, intermittent; sometimes ceasing for many nights, and sometimes
almost incessant during a part of every night. It is performed, as it
was with his father, with his right hand. One of his children, a girl,
has inherited the same trick. She performs it, likewise, with the right
hand, but in a slightly modified form; for after raising the arm, she
does not allow the wrist to drop upon the bridge of the nose, but the
palm of her half-closed hand falls over and down the nose, striking it
rather rapidly--a decided improvement on the father's and grandfather's
method. The trick is intermittent in this girl's case also, sometimes
not occurring for periods of several months but sometimes almost
incessantly.
Strength in particular limbs or muscles is often transmitted
hereditarily. So also is skill in special exercises. Thus in the north
country there are families of famous wrestlers. Among professional
oarsmen, again, we may note such cases as the Clasper family in the
north, the Mackinneys in the south; while among amateur oarsmen we have
the case of the Playford family, to which the present amateur champion
sculler belongs. In cricket, the Walker family and the Grace family
may be cited among amateurs, the Humphreys among professional players.
Grace in dancing was transmitted for three generations in the Vestris
family. It must, however, be noted that in some of these cases we may
fairly consider that example and teaching have had much to do with the
result. Take rowing for instance. A good oarsman will impart his style
to a whole crew if he rows stroke for them; and even if he only trains
them (as Morrison, for instance, trained the Cambridge crew a few years
ago), he will make good oarsmen of men suitably framed and possessing
ordinary aptitude for rowing. I remember well how a famous stroke-oar
at Cambridge (John Hall, of Magdalen,) imparted to one at least of the
University crew (a fellow-collegian of his, and therefore rowing with
him constantly also in his College boat) so exact an imitation of his
style that one rather dusky evening, when the latter was 'stroking' a
scratch four past a throng of University men, a dispute arose as to
which of the two was really stroke of the four. Anyone who knows how
characteristic commonly is the rowing of any first-class stroke, and
still more anyone who chances to know how peculiar was the style of the
University 'stroke-oar' referred to, will understand how closely his
style must have been adopted, when experienced oarsmen, not many yards
from the passing four, were unable to decide at once which of the two
men were rowing,--even though the evening was dusky enough to prevent
the features of the stroke (whose face was not fully in view at the
moment) from being discerned. Seeing that a first-rate oarsman can thus
communicate his style so perfectly to another, it cannot be regarded as
demonstrably a case of hereditary transmission if the Claspers rowed
in the same style as their father, or if the present champion amateur
sculler (making allowances for the change introduced by the sliding
seat) rows very much like his father and his uncle.
Some peculiarities, such as stammering, lisping, babbling, and the
like, are not easily referable to any special class of hereditary
traits, because it is not clear how far they are to be regarded as
depending on bodily or how far on mental peculiarities. It might seem
obvious that stammering was in most cases uncontrollable by the will,
and babbling might seem as certainly controllable. Yet there are cases
which throw doubt on either conclusion. Thus, Dr. Lucas tells us of
a servant-maid whose loquacity was apparently quite uncontrollable.
She would talk to people till they were ready to faint; and if there
were no human being to listen to her, she would talk to animals and
inanimate objects, or would talk aloud to herself. She had to be
discharged. 'But,' she said to her master, 'I am not to blame; it all
comes from my father. He had the same fault, and it drove my mother
to distraction; and his father was just the same.' Stammering has
been transmitted through as many as five generations. The same has
been noticed of peculiarities of vision. The Montmorency look, a sort
of half squint, affected nearly all the members of the Montmorency
family. The peculiarity called Daltonism, an inability to distinguish
between certain colours of the spectrum, was not so named, as is often
asserted, merely because the distinguished chemist Dalton was affected
by it, but because three members of the same family were similarly
affected. Deafness and blindness are not commonly hereditary where
the parents have lost sight or hearing either by accident or through
illness, even though the illness or accident occur during infancy; but
persons born either blind or deaf frequently if not commonly transmit
the defect to some at least among their offspring. Similar remarks
apply to deaf-mutism.
The senses of taste and smell must also be included in the list of
those which are affected by transmitted peculiarities. If we include
the craving for liquor among such peculiarities, we might at once
cite a long list of cases; but this craving must be regarded as
nervo-psychical, the sense of taste having in reality very little to
do with it. It is doubtful how the following hideous instance should
be classed. It is related by Dr. Lucas. 'A man in Scotland had an
irresistible desire to eat human flesh. He had a daughter; although
removed from her father and mother, who were both sent to the stake
before she was a year old, and although brought up among respectable
people, this girl, like her father, yielded to the horrible craving for
human flesh.' He must be an ardent student of physiological science who
regrets that at this stage circumstances intervened which prevented the
world from ascertaining whether the peculiarity would have descended to
the third and fourth generations.
Amongst the strangest cases of hereditary transmissions are those
relating to handwriting. Darwin cites several curious instances in
his _Variation of Plants and Animals under Domestication_. 'On what
a curious combination of corporeal structure, mental character, and
training,' he remarks, 'must handwriting depend. Yet everyone must have
noted the occasional close similarity of the handwriting in father and
son, even although the father had not taught the son. A great collector
of franks assured me that in his collection there were several franks
of father and son hardly distinguishable except by their dates.'
Hofacker, in Germany, remarks on the inheritance of handwriting, and it
has been even asserted that English boys when taught to write in France
naturally cling to their English manner of writing. Dr. Carpenter
mentions the following instance as having occurred in his own family,
as showing that the character of the handwriting is independent of
the special teaching which the right hand receives in this art:--'A
gentleman who emigrated to the United States and settled in the back
woods, before the end of last century, was accustomed from time to time
to write long letters to his sister in England, giving an account
of his family affairs. Having lost his right arm by an accident, the
correspondence was temporarily kept up by one or other of his children;
but in the course of a few months he learned to write with his left
hand, and before long, the handwriting of the letters thus written came
to be indistinguishable from that of his former letters.'
I had occasion two or three years ago to consider in an article on
'Strange Mental Feats,' in my _Science Byeways_, the question of
inherited mental qualities and artistic habits, and would refer the
reader for some remarkable instances of transmitted powers to that
article.[18] Galton in his work on _Hereditary Genius_, and Ribot in
his treatise on _Heredity_, have collected many facts bearing on this
interesting question. Both writers show a decided bias in favour of
a view which would give to heredity a rather too important position
among the factors of genius. Cases are cited which seem very little
to the purpose, and multitudes of instances are omitted which oppose
themselves, at a first view at any rate, to the belief that heredity
plays the first part in the genesis of great minds. Nearly all the
greatest names in philosophy, literature, and science, and a great
number of the greatest names in art, stand absolutely alone. We know
nothing achieved by the father or grandfather of Shakspeare, or of
Goethe, or Schiller, or Evans (George Eliot), or Thackeray, or Dickens,
or Huxley. None of Newton's family were in any way distinguished in
mathematical or scientific work; nor do we know of a distinguished
Laplace, or Lagrange, or Lavoisier, or Harvey, or Dalton, or Volta,
or Faraday, besides those who made these names illustrious. As to
general literature, page after page might be filled with the mere
names of those whose ancestry has been quite undistinguished. To say
that among the ancestors of Goethe, Schiller, Byron, and so forth,
certain qualities, virtues or vices, passions or insensibilities to
passion, may be recognised 'among the ancestors of men of science,
certain aptitudes for special subjects or methods of research,' among
the ancestors of philosophers and literary men certain qualities or
capabilities, and that such ancestral peculiarities determined the
poetic, scientific, or literary genius of the descendant, is in reality
to little purpose, for there is probably not a single family possessing
claims to culture in any civilised country among the members of which
individuals might not be found with qualities thus emphasised so to
speak. Such _à posteriori_ reasoning is valueless. If instances could
be so classified that after carefully studying them we could make
even the roughest approach to a guess respecting the cases in which a
family might be expected to produce men of any particular qualities,
there would be some use in these attempts at generalisation; at present
all that can be said is that some mental qualities and some artistic
aptitudes have unquestionably in certain instances been transmitted,
and that on the whole men of great distinction in philosophy,
literature, science, and art, are rather more likely than others to
have among their relations (more or less remote) persons somewhat above
the average in mental or artistic qualities. But it is not altogether
certain that this superiority is even quite so great as it might be
expected to be if hereditary transmission played no part at all in
the matter. For it cannot be denied that a great mathematician's son
has rather a better chance than others of being a mathematician, a
great author's son of being a writer, a great artist's son of being
skilful in art, a great philosopher's son of taking philosophic views
of things. Nearly every son looks forward while still young to the
time when he shall be doing his father's work; nearly every father
hopes while his children are yet young that some at least among them
will follow his pursuits. The fact that so few sons of great men do
follow in their fathers' footsteps shows that, despite the strong
ambition of the son and the anxious hope of the father, the son in the
majority of instances has not had ability even to take a fairly good
position in the work wherein the father has been perhaps pre-eminently
distinguished.