From Francis Galton, Memories of My Life

Chapter XX. Heredity

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 ha{re 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 summar' ise 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 4h that is to say, the names of the 41 very first men in Classics at Cambridge in each of these 4I 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, x Wordsworth, and x 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 I865, two preliminary papers in Mracmillan's 3fagaz£ne, 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 [52] 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. ,,

 

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 Athenaeum 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, Misloire des Sciences el des Savants defiuis deux Siecles, 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. Fart also. Dr. W. Fart (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 pounds 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 prizewinners 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, 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 187? 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 anaesthetic 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 cannula 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 Protector 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 2

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 their Corresponding Deviation from the Mean:

 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 -x, that at the 75th is + ~; so the difference between them is 5, and the half difference is x.

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 seeds men 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 I~ feet wide and 5 feet long, to dibble ten holes in each at equal distances apart, and x 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 onethird 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.x

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.

1 See Pres. Address, Section H, Brit. Assoc. Aberdeen, 1885 [87].

All the formulae 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 [9?], 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 Gausslan 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 Gausslan 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 acommon 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 sublety and insight as a mathematician. He was perhaps a little too nice and critical about his own work, losing time in overpolishing, 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 notdifficult 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 v&luable 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 dearly 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 Millals 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 [???], on what is now termed the "Ancestral Law," namely, that the average contribution of each parent is ¼, of each grandparent, 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.