HEREDITY
Early inquiries—_Hereditary Genius_—_English Men of
Science_—Family records—Nature and Nurture—Experiments on Free
Will—Pangenesis and transfusion of blood—Heredity concerned
with deviations—Experiments on peas—Regression—Ancestral law
The publication in 1859 of the _Origin of Species_ by Charles Darwin made
a marked epoch in my own mental development, as it did in that of human
thought generally. Its effect was to demolish a multitude of dogmatic
barriers by a single stroke, and to arouse a spirit of rebellion against
all ancient authorities whose positive and unauthenticated statements
were contradicted by modern science.
I doubt, however, whether any instance has occurred in which the
perversity of the educated classes in misunderstanding what they
attempted to discuss was more painfully conspicuous. The meaning of the
simple phrase “Natural Selection” was distorted in curiously ingenious
ways, and Darwinism was attacked, both in the press and pulpit, by
persons who were manifestly ignorant of what they talked about. This is
a striking instance of the obstructions through which new ideas have
to force their way. Plain facts are apprehended in a moment, but the
introduction of a new Idea is quite another matter, for it requires an
alteration in the attitude and balance of the mind which may be a very
repugnant and even painful process. On my part, however, I felt little
difficulty in connection with the _Origin of Species_, but devoured its
contents and assimilated them as fast as they were devoured, a fact which
perhaps may be ascribed to an hereditary bent of mind that both its
illustrious author and myself have inherited from our common grandfather,
Dr. Erasmus Darwin.
I was encouraged by the new views to pursue many inquiries which had
long interested me, and which clustered round the central topics of
Heredity and the possible improvement of the Human Race. The current
views on Heredity were at that time so vague and contradictory that
it is difficult to summarise them briefly. Speaking generally, most
authors agreed that all bodily and some mental qualities were inherited
by brutes, but they refused to believe the same of man. Moreover,
theologians made a sharp distinction between the body and mind of man,
on purely dogmatic grounds. A few passages may undoubtedly be found
in the works of eminent authors that are exceptions to this broad
generalisation, for the subject of human heredity had never been squarely
faced, and opinions were lax and contradictory. It seems hardly credible
now that even the word heredity was then considered fanciful and unusual.
I was chaffed by a cultured friend for adopting it from the French.
I had been immensely impressed by many obvious cases of heredity among
the Cambridge men who were at the University about my own time. The
Classical Class List was first established in 1824, consequently the
number of “Senior Classics” up to 1864 inclusive was 41, that is to say,
the names of the 41 very first men in Classics at Cambridge in each of
these 41 years were known and published. It will be sufficient as an
example to give the names of 7 of these Senior Classics, all of whom
had a father, brother, or son whose success was as notable as their own
(I count a Senior Wrangler as equal to a Senior Classic). They are: 3
Kennedys, 2 Lushingtons, 1 Wordsworth, and 1 Butler. This fact alone
would justify a serious attempt to inquire into Hereditary Ability, and I
soon found the power of heredity to be as fully displayed in every other
direction towards which I turned. The Myttons mentioned in Chapter VIII.
were an unquestionable instance of a very peculiar hereditary temperament.
After many months of hard work, I wrote, in 1865, two preliminary
papers in _Macmillan’s Magazine_, entitled “Hereditary Talent and
Character”[20]. These contain the germs of many of my subsequent
memoirs, the contents of which went to the making of the following
books: _Hereditary Genius_, 1869; _English Men of Science_, 1874; _Human
Faculty_, 1883; _Natural Inheritance_, 1889; and to my quite recent
writings on Eugenics. On re-reading these articles, I must say that,
considering the novel conditions under which they were composed, and
notwithstanding some crudeness here and there, I am surprised at their
justness and comprehensiveness. It has fortunately been my usual habit
(sometimes omitted) of keeping copies of my various memoirs, which are
now bound in volumes. There are considerably more than a hundred and
seventy publications in all, as will be gathered from the not wholly
complete list in the Appendix, and I am pleased to find myself still in
accord with nearly every one of those recently re-read or referred to.
_Hereditary Genius_[22] made its mark at the time, though subjected to
much criticism, no small part of which was captious or shallow, and
therefore unimportant. The verdict which I most eagerly waited for was
that of Charles Darwin, whom I ranked far above all other authorities on
such a matter. His letter, given below, made me most happy.
“DOWN, BECKENHAM, KENT, S.E.
_3rd December_
“MY DEAR GALTON,—I have only read about 50 pages of your book
(to Judges), but I must exhale myself, else something will
go wrong in my inside. I do not think I ever in all my life
read anything more interesting and original—and how well and
clearly you put every point! George,[8] who has finished the
book, and who expressed himself in just the same terms, tells
me that the earlier chapters are nothing in interest to the
later ones! It will take me some time to get to these latter
chapters, as it is read aloud to me by my wife, who is also
much interested. You have made a convert of an opponent in one
sense, for I have always maintained that, excepting fools, men
did not differ much in intellect, only in zeal and hard work;
and I still think this is an _eminently_ important difference.
I congratulate you on producing what I am convinced will prove
a memorable work. I look forward with intense interest to each
reading, but it sets me thinking so much that I find it very
hard work; but that is wholly the fault of my brain and not of
your beautifully clear style.—Yours most sincerely,
“(Signed) CH. DARWIN”
The rejoinder that might be made to his remark about hard work, is that
character, _including the aptitude for work_, is heritable like every
other faculty.
I had been overworked, and unable to give as close attention as desirable
while correcting the proofs, so mistakes were to be feared. Happily there
were not many, but one was absurd, and I was justly punished. It was due
to some extraordinary commingling of notes on the families of Jane Austen
and of Austin the jurist. In my normal state of health the mistake could
not have been overlooked, but there it was. I was at that time a member
of the Committee of the Athenæum Club, among whose members there happened
to be a representative of each of the above families, who “gave it me
hot,” though most decorously.
I had much pleasant correspondence at a later date with Alphonse de
Candolle, son of the still greater botanist of that name. He had written
a very interesting book, _Histoire des Sciences et des Savants depuis
deux Siècles_, in which he analysed the conditions that caused nations,
and especially the Swiss, to be more prolific in works of science at one
time than another, and I thought that a somewhat similar investigation
might be made with advantage into the history of English men of science.
It was a daring undertaking, to ask as I did, in 1874, every Fellow
of the Royal Society who had filled some important post, to answer a
multitude of Questions needful for my purpose, a few of which touched
on religion and other delicate matters. Of course they were sent on the
distinct understanding that the answers would be used for statistical
purposes only. I took advice on the subject, notably of Herbert Spencer,
and I think (though I cannot say for certain) from Dr. W. Farr also. Dr.
W. Farr (1807-83) was the head of the Registration Department in Somerset
House. I frequently consulted him, and always to my advantage, for he
was highly gifted and cultured. He was most sympathetic, and keenly
appreciated what might be called the poetical side of statistics, as
shown by his Annual Reports and other publications.
The size of my circular was alarming. Though naturally very shy, I
do occasional acts, like other shy persons, of an unusually bold
description, and this was one. After an uneasy night, I prepared myself
on the following afternoon, and not for the first time before interviews
that were likely to be unpleasant, by what is said to have been the
usual practice of Buffon before writing anything exceptional, namely, by
dressing myself in my best clothes.
I can confidently recommend this plan to shy men as giving a sensible
addition to their own self-respect, and as somewhat increasing the
respect of others. In this attire I went to a meeting of the Royal
Society, prepared to be howled at; but no! my victims, taken as a whole,
tolerated the action, and some even approved of it.
Much experience of sending circular questions has convinced me of the
impossibility of foretelling whether a particular person will receive
them kindly or not. Some are unexpectedly touchy. In this very case, a
man of high scientific distinction, with whom I was well acquainted,
who was of good social position, of whose family many details were
already known to me, all of which were honourable, and whose biography
has since disclosed no skeleton in the cupboard, was almost furious at
being questioned. On the other hand, a Cabinet Minister, whom I knew but
slightly, gave me full and very interesting information without demur.
The results of the inquiry showed how largely the aptitude for
science was an inborn and not an acquired gift, and therefore apt to
be hereditary. But, in not a few instances, the person who replied
was a “sport,” being the only one of his family who had any care for
science, and who had persevered in spite of opposition. The paternal
influence generally superseded the maternal in early life, though the
mother was usually spoken of with much love, and very often described
as particularly able. This seemed to afford evidence that the virile,
independent cast of mind is more suitable to scientific research than
the feminine, which is apt to be biased by the emotions and to obey
authority. But I have said my say long since in the book _English Men of
Science_[36], and must not reiterate.
The dearth of information about the Transmission of Qualities among
all the members of a family during two, three, or more generations,
induced me in 1884-85 to offer a sum of £500 in prizes to those who
most successfully filled up an elaborate list of questions concerning
their own families. The questions were contained in a thin quarto volume
of several pages, printed and procurable at Macmillan’s, cost price,
which referred to the Grandparents, Parents, Brothers, Sisters, and
Children, with spaces for more distant relatives. A promise was given,
and scrupulously kept, that they should be used for statistical purposes
only. My offer had a goodly response, and the names of the prize-winners
were duly published in the newspapers. I was much indebted, when devising
the programme and other prefatory details, both to Professor Allman
(1812-1898), the biologist, and to my old friend at King’s College,
Mr. (afterwards Sir) John Simon. The material afforded by the answers
proved of considerable importance, and formed the basis of much of my
future work. I had it extracted in a statistical form, in considerable
detail, which was of much value to Professor Karl Pearson at the outset
of his inquiries, before he had been able to collect better and much more
numerous data of his own. It will be convenient to defer speaking of the
results of all this until the last chapter.
I had long tried to gain some insight into the relative powers of Nature
and Nurture, in order that due allowance might be made for Environment,
neither too much nor too little, but without finding an adequate method
of obtaining it. At length it occurred to me that the after-history of
those twins who had been closely alike as children, and were afterwards
parted, or who had been originally unlike and afterwards reared together,
would supply much of what was wanted. So I inquired in all directions
for appropriate cases, and at length obtained a fair supply, on which an
article in _Frazer’s Magazine_, Nov. 1875,[9] was written. The evidence
was overwhelming that the power of Nature was far stronger than that of
Nurture, when the Nurtures of the persons compared were not exceedingly
different. It appeared that when twins who had been closely alike had
afterwards grown dissimilar, the date of divergence was usually referred
to a time when one of them had a serious illness, sufficient to modify
his constitution.
Many years later I was so harassed with the old question of Determinism,
which would leave every human action under the control of Heredity and
Environment, that I made a series of observations on the actions of
my own mind in relation to Free Will. I employ the word not merely as
meaning “unhindered” but in the _special_ sense of an _uncaused_ and
_creative_ action. It was carried on almost continuously for six weeks,
and off and on for many subsequent months[55]. The procedure was this.
Whenever I caught myself in an act of what seemed to be “Free Will”
in the above sense, I checked myself and tried hard to recollect what
had happened before, made rapid notes, and then wrote a full account
of the case. To my surprise, I found, after some days’ work, that the
occasions were rare on which there seemed room for the exercise of Free
Will as defined above. I subsequently reckoned that they did not occur
oftener than once a day. Motives for all the other events could be traced
backwards in succession, by orderly and continuous steps, until they led
into a tangle of familiar paths. It was curious to watch the increase of
power given by practice, of recalling mental actions which being usually
overlooked give the false idea that much has been performed through a
creative act, or by inspiration, which is really due to straightforward
causation. The subject is too complex to be more fully gone into here;
I must refer to the Memoir itself. The general result of the inquiry
was to support the views of those who hold that man is little more than
a conscious machine, the slave of heredity and environment, the larger
part, perhaps all, of whose actions are therefore predictable. As regards
such residuum as may not be automatic but creative, and which a Being,
however wise and well-informed, could not possibly foresee, I have
nothing to say, but I found that the more carefully I inquired, whether
it was into hereditary similarities of conduct, into the life-histories
of twins, or introspectively into the actions of my own mind, the smaller
seemed the room left for this possible residuum.
* * * * *
Many possibilities suggested themselves after reading Darwin’s
“Provisional theory of Pangenesis.” One was that the breed of a race
might be sensibly affected by the transfusion of blood from another
variety. According to Darwin’s theory, every element of the body throws
off gemmules, each of which can reproduce itself, and a combination of
these gemmules forms a sexual element. If so, I argued, the blood which
conveys these gemmules to the places where they are developed, whether
to repair an injured part or to the sexual organs, must be full of
them. They would presumably live in the blood for a considerable time.
Therefore, if the blood of an animal of one species were largely replaced
by that of another, some effect ought to be produced on its subsequent
offspring. For example, the dash of bull-dog tenacity that is now given
to a breed of greyhounds by a single cross with a bull-dog, the first
generation corresponding to a mulatto, the second to a quadroon, the
third to an octoroon, and so on, might be given at once by transfusion.
Bleeding is the simplest of operations, and I knew that transfusion had
been performed on a large scale; therefore I set about making minute
inquiries.
These took a long time, and required much consideration. At length
I determined upon trying the experiment on the well-known breed of
rabbits called silver greys, of which pure breeds were obtainable,
and to exchange much of their blood for that of the common lop-eared
rabbit; afterwards to breed from pairs of silver greys in each of
which alien blood had been largely transfused. This was done in 1871
on a considerable scale. I soon succeeded in establishing a vigorous
cross-circulation that lasted several minutes between rabbits of
different breeds, as described in the _Proceedings of the Royal Society_,
1871[25]. The experiments were thorough, and misfortunes very rare. It
was astonishing to see how quickly the rabbits recovered after the effect
of the anæsthetic had passed away. It often happened that their spirits
and sexual aptitudes were in no way dashed by an operation which only a
few minutes before had changed nearly one half of the blood that was in
their bodies. Out of a stock of three silver grey bucks and four silver
grey does, whose blood had been thus largely adulterated, and of three
common bucks and four common does whose blood had been similarly altered,
I bred eighty-eight rabbits in thirteen litters without any evidence of
alteration of breed. All this is described in detail in the Memoir.
I was indebted to expert friends for making these delicate operations,
my own part was confined to inserting cannulæ and the like. At first Dr.
Murie did all the dexterous and difficult work. He had been a traveller
in company with Consul Petherick, far up the White Nile, and was then
Prosector at the Zoological Gardens. I called on him to discuss the
matter. A dead cobra was lying on his table, and on my remarking that I
had never properly seen a poison fang, he coolly opened the creature’s
mouth, pressed firmly at exactly the right spot, and out started that
most delicate and wicked-looking thing, with a drop of venom exuding from
it, just in front of his nail. I thought that a man who was so confident
of his anatomical knowledge and of his nerve as to dare such an act,
must be an especially suitable person to conduct my experiments, and was
fortunate enough to secure his co-operation.
I continued the experiments for another generation of rabbits beyond
those described in the _Proc. Royal Society_, with equally negative
results. Mr. Romanes subsequently repeated the experiments with my
instruments, and they corroborated my own. So this point seems settled.
* * * * *
The laws of Heredity are concerned only with deviations from the Median,
which have to be translated from whatever they were measured by, whether
in feet, pounds weight, intervals of time, or any other absolute
standard, into what might be called “Statistical Units.” Their office is
to make the variabilities of totally different classes, such as horses,
men, mice, plants, proficiency in classics, etc. etc., comparable on
equal terms. The statistical unit of each series is derived from the
series itself. There is more than one kind of them, but they are all
mutually convertible, just as measures recorded in feet are convertible
into inches. The most convenient unit for purpose of explanation, though
not for calculation, is the half difference between the marks or measures
corresponding to the lower or to the upper quantities respectively.[10]
Deviations expressed in statistical units are usually found to conform
with much closeness to the results of a certain theoretical law,
discovered by Gauss, the great mathematician, and properly called by his
name, though more familiarly known as the Normal Law. It supposes all
variability to be due to different and equally probable combinations
of a multitude of small independent causes. The relative frequency
of different amounts of these, reckoned in statistical units, can
thence be computed. It is done by refined methods based on the same
general principles as those by which sequences of different lengths, in
successive throws of dice, are determined.
Results of the computation are shown in the bottom line of the following
small table:—
_Centiles and Corresponding Deviation from the Median._
+----------+-----+-----+-----+-----+-----+-----+-----+-----+-----+
|Centiles | 10th| 20th| 30th| 40th| 50th| 60th| 70th| 80th| 90th|
+----------+-----+-----+-----+-----+-----+-----+-----+-----+-----+
|Deviations|-1·90|-1·25|-0·78|-0·38| -0 |+0·38|+0·78|+1·25|+1·90|
+----------+-----+-----+-----+-----+-----+-----+-----+-----+-----+
The deviation at the 25th is -1, that at the 75th is +1; so the
difference between them is 2, and the half difference is 1.
As these lines are being written, the circumstances under which I first
clearly grasped the important generalisation that the laws of Heredity
were solely concerned with deviations expressed in statistical units, are
vividly recalled to my memory. It was in the grounds of Naworth Castle,
where an invitation had been given to ramble freely. A temporary shower
drove me to seek refuge in a reddish recess in the rock by the side of
the pathway. There the idea flashed across me, and I forgot everything
else for a moment in my great delight.
The following question had been much in my mind. How is it possible for
a population to remain alike in its features, as a whole, during many
successive generations, if the _average_ produce of each couple resemble
their parents? Their children are not alike, but vary: therefore some
would be taller, some shorter than their average height; so among the
issue of a gigantic couple there would be usually some children more
gigantic still. Conversely as to very small couples. But from what I
could thus far find, parents had issue less exceptional than themselves.
I was very desirous of ascertaining the facts of the case. After much
consideration and many inquiries, I determined, in 1885, on experimenting
with sweet peas, which were suggested to me both by Sir Joseph Hooker
and by Mr. Darwin. Their merits are threefold. They have so little
tendency to become cross-fertilised that seedsmen do not hesitate to
grow differently coloured plants in neighbouring beds; all the seeds
in their pods are of the same size, that is to say, there is no little
pea at the end as in the pod of the common pea, and they are very hardy
and prolific. I procured a large number of seeds from the same bin, and
selected seven weights, calling them K (the largest), L, M, N, O, P, and
Q (the smallest), forming an arithmetic series. Curiously, their lengths,
found by measuring ten of a kind in a row, also formed an arithmetic
series, owing, I suppose, to the larger and plumper seeds being more
spherical and therefore taking less room for their weight than the
others. Ten peas of each of these seven descriptions, seventy in all,
formed what I called a “set.”
I persuaded friends living in various parts of the country, each to plant
a set for me. The uniform method to be followed was to prepare seven
parallel beds, each 1½ feet wide and 5 feet long, to dibble ten holes in
each at equal distances apart, and 1 inch in depth, and to put one seed
in each hole. The beds were then to be bushed over to keep off the birds.
As the seeds became ripe they were to be gathered and put into bags which
I sent, lettered respectively from K to Q; the same letters having been
stuck at both ends of the beds. Finally, when the crop was coming to an
end, the whole foliage of each row was to be torn up, tied together, and
sent to me. All this was done, and further minute instructions, which I
need not describe here, were attended to carefully. The result clearly
proved _Regression_; the mean Filial deviation was only one-third that
of the parental one, and the experiments all concurred. The formula
that expresses the descent from one generation of a people to the
next, showed, that the generations would be identical if this kind of
_Regression_ was allowed for.[11]
In 1886 I contributed two papers [91], [92] to the Royal Society on
Family Likeness, having by that time got my methods for measuring
heredity into satisfactory shape. I had given much time and thought to
Tables of Correlations, to display the frequency of cases in which the
various deviations say in stature, of an adult person, measured along
the top, were associated with the various deviations of stature in his
mid-parent, measured along the side. (I had long used the convenient
word “mid-parent” to express the average of the two parents, after the
stature or other character of the mother had been changed into its male
equivalent.) But I could not see my way to express the results of the
complete table in a single formula. At length, one morning, while waiting
at a roadside station near Ramsgate for a train, and poring over the
diagram in my notebook, it struck me that the lines of equal frequency
ran in concentric ellipses. The cases were too few for certainty, but my
eye, being accustomed to such things, satisfied me that I was approaching
the solution. More careful drawing strongly corroborated the first
impression.
All the formulæ of Conic Sections having long since gone out of my head,
I went on my return to London to the Royal Institution to read them up.
Professor, now Sir James, Dewar, came in, and probably noticing signs of
despair in my face, asked me what I was about; then said, “Why do you
bother over this? My brother-in-law, J. Hamilton Dickson of Peterhouse,
loves problems and wants new ones. Send it to him.” I did so, under
the form of a problem in mechanics, and he most cordially helped me by
working it out, as proposed, on the basis of the usually accepted and
generally justifiable Gaussian Law of Error. So I begged him to allow his
solution to be given as an appendix to my paper[91], where it will be
found.
It had appeared from observation, and it was fully confirmed by this
theory, that such a thing existed as an “Index of Correlation”; that is
to say, a fraction, now commonly written _r_, that connects with close
approximation every value of deviation on the part of the subject, with
the _average_ of all the associated deviations of the Relative as already
described. Therefore the closeness of any specified kinship admits of
being found and expressed by a single term. If a particular individual
deviates so much, the _average_ of the deviations of all his brothers
will be a definite fraction of that amount; similarly as to sons,
parents, first cousins, etc. Where there is no relationship at all, _r_
becomes equal to 0; when it is so close that Subject and Relative are
identical in value, then _r_ = 1. Therefore the value of _r_ lies in
every case somewhere between the extreme limits of 0 and 1. Much more
could be added, but not without using technical language, which would be
inappropriate here.
The problem as described above is by no means difficult to a fair
mathematician. Mr. J. H. Dickson set it to a class of his higher
students, most of whom answered it. It has since been remarked that this
same mechanical problem had been solved still more comprehensively by a
French mathematician. Professor Karl Pearson subsequently extended its
application to variables not governed by the Gaussian Law, and the exact
determination of the Index of Correlation by his refined method has now
become the object of most biometric work.
I have received much help at various times from Mathematical friends. On
one occasion, being impressed with the probability (owing to Weber’s and
Fechner’s Laws) that the true mean value of many of the qualities with
which I dealt would be the Geometric and not the Arithmetic Mean, I asked
Mr. Donald Macalister, of whom I have already spoken, to work out the
results. He, as a schoolboy, was the first to gain the prize medal of the
Royal Geographical Society, then became the Senior Wrangler of his year
at Cambridge, subsequently Chairman of the Medical Council, and is now
Provost of Glasgow University. His memoir is supplementary to mine on the
“Geometric Mean,” _Proceedings of the Royal Society_, 1879[53].
My first serious interest in the Gaussian Law of Error was due to the
inspiration of William Spottiswoode, who had used it long ago in a
Geographical memoir for discussing the probability of the elevations of
certain mountain chains being due to a common cause. He explained to me
the far-reaching application of that extraordinarily beautiful law, which
I fully apprehended. I had also the pleasure of making the acquaintance
of Quetelet, who was the first to apply it to human measurements, in its
elementary binomial form, which I used in my _Hereditary Genius_.
The mathematician who most frequently helped me later on was the Rev. H.
W. Watson, who moreover worked out for me the curious question of the
“Probability of the Extinction of Families”[40]. It appeared in 1875 in
the _Proceedings of the Royal Society_ as a joint paper, at his desire;
but all the hard work was his: I only gave the first idea and the data.
He helped me greatly in my first struggles with certain applications of
the Gaussian Law, which, for some reasons that I could never clearly
perceive, seemed for a long time to be comprehended with difficulty by
mathematicians, including himself. They were unnecessarily alarmed lest
the well-known rules of Inverse Probability should be unconsciously
violated, which they never were. I could give a striking case of
this, but abstain because it would seem depreciatory of a man whose
mathematical powers and ability were far in excess of my own. Still, he
was quite wrong. The primary objects of the Gaussian Law of Error were
exactly opposed, in one sense, to those to which I applied them. They
were to get rid of, or to provide a just allowance for errors. But these
errors or deviations were the very things I wanted to preserve and to
know about. This was the reason that one eminent living mathematician
gave me.
The patience of some of my mathematical friends was tried in endeavouring
to explain what I myself saw very clearly as a geometrical problem, but
could not express in the analytical forms to which they were accustomed,
and which they persisted in misapplying. It was a gain to me when I had
at last won over Mr. Watson, who put my views into a more suitable shape.
H. W. Watson was Second Wrangler of his year, and had the reputation
among his college fellows of extraordinary subtlety and insight as a
mathematician. He was perhaps a little too nice and critical about his
own work, losing time in over-polishing, so that the amount of what he
produced was lessened. He wrote on the _Kinetic Theory of Gases_.
I may mention two anecdotes about him. He had been a good Alpine climber
and met with various incidents. One was that he and a friend, F. Vaughan
Hawkins, set off at a good pace to vanquish some new but not difficult
peak, and passed on their way a somewhat plodding party of German
philosophers bound on the same errand. One of Watson’s shoes had shown
previous signs of damage, but he thought he could manage to get on for
a day or two longer if he now and then covered it with an indiarubber
galosh that he then took with him for such emergencies. It was a cumbrous
addition, but succeeded fairly, and he and his friend reached the top
long before the Germans, whom they thought no more about. However,
shortly after, a Swiss-German newspaper gave a somewhat grandiose account
of the ascent of the mountain in question by Professors This and That, in
which it was remarked that the Professors would have been the very first
to reach its summit had not two jealous Englishmen provided themselves
with “Gummi Schuhe” and so were able to outstrip them.
The other anecdote refers to the circumstances under which Watson became
Rector of a valuable living, that of Berkswell, near Coventry. I repeat
the tale to the best of my remembrance as he told it me, but doubtless
with mistakes in a few details. He was a Master at Harrow when some
scrape had occurred, and a boy in whom he was interested was judged
guilty and sent up to be flogged. The boy protested his innocence so
vehemently, that although appearances were sadly against him, Watson was
ready to believe what he said, and took unusual pains to investigate the
matter. The result was that the boy was completely exculpated. A few
years after, the boy’s father bought the property at Berkswell in which
the gift of the living was included. It happened to be then vacant, and
the new proprietor found he must either nominate some one at once, or
the nomination would lapse, and fall (I think) to the Bishop. He knew of
no suitable clergyman. Then the boy called out, “Give it to Mr. Watson,”
which the father, knowing the story, did.
* * * * *
I thought that some data which were needed might be obtained by breeding
insects, without too great expenditure of time and money, and it ended
in my selecting for the purpose, under the advice of Mr. Merrifield, a
particular kind of Moth, the “Selenia illustraria,” which breeds twice
a year and is hardy. Mr. Merrifield most kindly undertook to conduct
the experiments for me, and his methods were beautifully simple and
suitable. They are described in the _Transactions of the Entomological
Society, 1887_[100]. Another friend also undertook a set. I will not
describe any of the results at length, because they failed owing to
rapidly diminishing fertility in successive generations, and through the
large disturbing effects of small differences in environment. All the
moths in the first generation were photographed neatly on octavo pages
by a friend, Miss Reynolds, and a very great deal of trouble was taken
about them, but all in vain. The only consolation that I have is that
the experiences gained by Mr. Merrifield enabled him to pursue other
experiments on moths with great success, which have led to his increased
reputation as an entomologist.
Later still it seemed most desirable to obtain data that would throw
light on the _Average_ contribution of each Ancestor to the total
heritage of the offspring in a mixed population. This is a purely
statistical question, the same answer to which would be given on more
than one theoretical hypothesis of heredity, whether it be Pangenetic,
Mendelian, or other.
I must stop for a moment to pay a tribute to the memory of Mendel, with
whom I sentimentally feel myself connected, owing to our having been
born in the same year 1822. His careful and long-continued experiments
show how much can be performed by those who, like him and Charles
Darwin, never or hardly ever leave their homes, and again how much
might be done in a fixed laboratory after a uniform tradition of work
had been established. Mendel clearly showed that there were such things
as alternative atomic characters of equal potency in descent. How far
characters generally may be due to simple, or to molecular characters
more or less correlated together, has yet to be discovered.
I had thought of experimenting with mice, as cheap to rear and very
prolific, and had taken some steps to that end, when I became aware of
the large collections of Basset Hounds belonging to the late Sir Everard
Millais. He offered me every facility. The Basset Hound records referring
to his own and other breeds had been carefully kept, and the Stud Book he
lent me contained accounts of nearly 1000 animals, of which I was able
to utilise 817. All were descended from parents of known colours; in 567
of them the colours of all four grandparents were also known. Wherever
the printed Stud Book was deficient, Sir Everard Millais supplied the
want in MS from the original records. My inquiry was into the heredity of
two alternative colours, one containing no black, the other containing
it; their technical names were lemon-white and tri-colour (black, lemon,
white) respectively. I was assured that no difficulty was felt in
determining the category to which each individual belonged. These data
were fully discussed in a memoir, published (1897) in the _Proceedings
of the Royal Society_[139], on what is now termed the “Ancestral Law,”
namely, that the _average_ contribution of each parent is ¼, of each
grandparent ⅟₁₆, and so on. Or, in other words, that of the two parents
taken together is ½, of the four grandparents together ¼, and so on.
My data were not as numerous as is desirable, still the results were
closely congruous, and seem to be a near approximation to the truth. The
conclusions have been much discussed and criticised, and they have been
modified by Professor Karl Pearson; but they have not been seriously
shaken, so far as I know.