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From The Westminster Review.

MARRIAGES OF CONSANGUINITY.

opinion, a moral theory, a social predilection, a fact in his own family or personal history

1. On Marriages of Consanguinity. Dr. Be- any or all of these may, consciously or unconmiss. Journal of Psychological Medi-sciously, so modify his view of what ought to cine for April, 1857. be a mere question of fact, as to render him a 2. Hygiene de Famille. Dr. Devay. totally unsafe guide in any subject-matter

Edition.

Second
Papers plain. The history of the scientific question
forming the subject of this article will be
found to illustrate these remarks even better

which he has undertaken to examine and ex

3. Comptes Rendus, 1852-3, passim.
by MM. Boudin, Sanson, Beaudouin,
Gourdon, etc.

4. On Marriages of Consanguinity. Dr. Child,
in Medico-Chir. Review, April, 1862; than most others.
and Medical Times, April 25th, 1863.

That there has existed, at least in all mod

5. On the Fertilization of Orchids. Mr. Dar-ern times, what is called a "feeling "against

win. London. 1862.

the intermarriage of blood relations, is a fact If we had to point out the tendency or that cannot be denied, but of which the scienhabit of mind which, more than any other, tific value cannot be rated very high. Before has served, in modern times, to hinder the we admit the existence of such a feeling as progress of real knowledge, we should fix even primâ facie evidence, we should rememupon that which impels not a few really able ber how often such have been found to rest and competent persons, when undertaking an either upon no ground at all, or upon an eninvestigation, first of all to adopt a theory, tirely mistaken one. The biting cold of the and then to look at the facts which nature winter months in England used to be called propresents to them by its light exclusively. verbially" fine, seasonable, healthy weather,” Such persons do not take up a hypothesis for until the Registrar-General's statistics had its legitimate use, as a guide in experimenta- proved to the apprehension almost of the dulltion, as any one pursuing an investigation in est, that mortality in our climate rises pari the science of light would in these days start passu with the fall of the thermometer. In upon the undulatory theory, but adopt it with this case, doubtless the popular delusion took a confidence in its absolute truth which renders its rise from the sense of exhilaration and them utterly blind to all facts which cannot buoyancy felt by healthy, strong, and youthbe reconciled with it, and by consequence ex-ful persons on a bright frosty day, as comaggerates out of all due proportion the impor-pared with the dulness and languor experitance of those which really make in its favor. enced on a damp and warm one; but it entirely Of the many inconveniences attendant upon the state of mind of which we speak, one of the gravest and quite the most paradoxacal is to be found in the fact that its mischievous results always bear a direct ratio to the ability and industry of the person whom it affects. A man of real power who sets out upon a research into a complicated subject under such conditions as we have indicated, is sure to make out a good case in favor of his own preconceived view, and by so doing he will mislead others and hinder the advance of knowledge in a degree exactly proportioned to his own ability and reputation. Instances of the kind to which we refer will occur to any

reader familiar with the history of almost any scientific question. But there is one feature in such cases which is especially worthy of remark; it is, that a man's preconceived notions upon any subject may take their rise from something quite distinct from, and external to, the subject itself; a religious

left out of the account the less obvious but more really potent influence of cold upon the old, the feeble, and the ill-provided. In the case before us, the following has been suggested by Dr. Child as the not improbable history of the prevailing opinion :

"It should be remembered that all such

marriages as those under discussion, were and are strictly prohibited in the Church of Rome. This prohibition was first removed in England by the Marriage Act of 1540, in the reign of Henry VIII: It is natural, therefore, that many people at the time should have looked upon this removal of restrictions as a somewhat questionable concession to human weakness, and upon the marriages made in consequence of it, as merely not illegal, rather than in themselves unobjectionable; just as, should the Marriage Law Amendment Bill pass into law, their can be no doubt that many would now look upon marriage with a sister-in-law as a very questionable proceeding in a social *"Med. Chir. Review." Vol. xxix. p. 469.

We turn now from the consideration of the

and religious point of, view, although they rejection of M. Littré by the Institute, threaten might possibly be unable to impugn its strict to make such triumphs commonplace. legality. Under such circumstances nothing is more natural, especially in an age when men were much more open to theological than physiological considerations, than that they should attribute any ill effect which might seem to follow from such unions to the special intervention of Providence. Such ill effects would be marked and noticed whenever they occurred, and would soon become proverbial; and when, in a later age, men began to pay more attention to the breeding of animals, and found that excessively close breeding seemed, in some cases, to produce similar results, they would be led to establish a false analogy between the two cases, and to infer the existence of a law of nature which close breeding and consanguineous marriages equally infringed.

66

Something like this I conceive to be the true history of the common opinion upon this subject, an opinion, which, as far as I can discover, rests on no satisfactory record of

observed facts."

We are induced to insist the more strongly upon this aspect of the question because the works even of modern and professedly scientific writers bear witness both to the universality of this popular prejudice, and to the probability of its theological or rather ecclesiastical origin. Thus Niebuhr * speaks of the Ptolemies, whose history certainly affords the most striking instance on record of close breeding in the human race, as degenerate both in body and soul. He seems to forget that their dynasty continued for some three hundred years, and that the history of Cleopatra, the last sovereign, though not the last descendant of their line, is certainly not that of a person, in any intelligible sense of the words, degenerate both in body and mind. But the most remarkable instance is afforded by Dr. Devay, who, while writing especially on this subject in his work on Hygiene, which he professes to treat scientifically, occupies no small portion of the two chapters devoted to it with a long citation of fathers and doctors of the Church, from St. Augustine down to the contemporary Archbishop of Tours. Truly it might be considered a rare treat for orthodox Frenchmen in these skeptical days to find such authorities polled to settle a scientific question, were it not that a few recent events, such as the late

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spirit in which inquiries into our present subject have been undertaken, and proceed to give a succinct account of the facts and arguments which have been brought forward on both sides of the question, that our reader may have an opportunity of seeing what real value belongs to them, and to which side the balance of the evidence inclines. This evidence is derived from two distinct sources, which differ in their subject-matter, in the method by which they can be investigated, and in the degree of certitude which attaches to them as far as they severally go, no less than in the conclusion to which they lead. These are, 1, experience derived from the study of mankind by means of recorded observation and statistics; and 2, that drawn from the study of the lower animals and even of plants, which admits of being brought to the test of strict experiment as well as of observation. The former of these methods has been pursued with much diligence by Dr. Bemiss, MM. Boudin, Devay, and others. We give a short summary of the results arrived at by these observers, in order that our readers may be able at a glance to comprehend the several points to which we shall have to direct their attention.

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DR. DEVAY.

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DR. BEMISS. Marriage Fruitful Sterile. Total Children 192 This gives in Dr. Bemiss's cases an average number of 5.6 children to each marriage; in Dr. Howe's 5.58 to each. The average number of births to each marriage in England was recently 4.5. Of the 192 children born, 58 died in early life, and 134 reached" maturity;" i.e., the number of early deaths was as 1 to 3.3. The average of deaths under 5 years old, as stated by Dr. West, is 1 to 3. It is thus clear that while the fertility of these marriages was much above the average, the infant mortality in their offspring was slightly below. In Dr. Devay's cases the total number of children is not given, and therefore no calculation on the point can be made.

In consequence of the different principles upon which these authors have arranged their statistics, it is impossible to exhibit

them at length in a tabular form, or indeed | obstruction which it is capable of throwing to contrast them at all in detail; we must in the way of the progress of knowledge when therefore content ourselves with stating that used upon a subject-matter to which it is unthe relation of the principal forms of disease suited. It may be applied, with every prosor defects mentioned by them varies as fol- pect of a successful result, in cases with which lows:human volition has nothing to do, as it has been so applied to elucidate facts in pathology, such as the probability of death from a particular disease at a particular time of life.

DR. BEMISS.

In 75 Cases of Disease. Scrofula and Consumption 38 or Epilepsy and Spasmodic Dis.

Deafness

Idiotcy.
Deformity.

DR. HOWE.
Cases of Dis.
12 or 207

In 58

506

12 or

16

0

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From the loose form in which Dr. Devay's results are stated, we are able to contrast his statement with the above in one point only, namely, that of deformity, which appears in 27 out of 52 cases, or 519 as against 026 in one of the other cases, and 0 in the other.

M. Boudin's statistics are of a different character and on a much larger scale. He takes merely the one defect of deaf-mutism, and finds 1st, That while consanguineous marriages are 2 per cent. of all marriages in France, the number of deaf-mutes born of such marriages are, to all deaf-mutes,—

In Lyons
In Paris

In Bordeaux

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25 per cent.
28 per cent.
30 per cent.

Often, too, when the will of man is an element in the calculation, but when that will can be shown to be swayed by conflicting motives, the comparative power of which it is impossible to guage, a judicious application of the statistical method, if only the number of instances collected be sufficiently large, may enable us to arrive at a conclusion at least approximately true. But it does not follow from the full admission of all this, that the same method can be followed in cases such as that before us, and with a view to ascertain the causes as well as the circumstances of the phenomena to which it is applied. Thus, it may be true that we can ar

rive at the number of murders which will be committed in a population of a certain extent in a given time, but it does not follow that we can also tell what is the cause of all these murders, or that they all depend upon the He finds further: 2d, that the danger of deaf same cause. Moreover, a murder is a fact and dumb offspring increases with the near- which is usually discovered, quite indepenness of kinship between the parents; 3d, dently of human testimony as to its mere ocThat parents themselves deaf and dumb, do currence; and if it is the interest of the pernot, as a rule, produce deaf and dumb off-petrator and his friends to conceal it, it is spring, and that the defect is therefore not equally that of the friends of the victim to hereditary; 4th, That the number of deaf-make it known. On the other hand, it is obmutes increases in proportion to the local vious that the value of statistics such as those difficulties to freedom of cross-marrying the results of which we have just given dethus it is inpends upon the truth of a number of family 6 in 10,000. histories. These are all matters of testimony, 14 in 10,000. and the motives to falsification thereof lie all 23 in.10,000. on the same side. There is, perhaps, as most 28 in 10,000. lawyers and physicians are well aware, no Before entering upon any examination of point in which men are so morbidly sensitive these particular statistics, it is necessary to and suspicious as one which touches a family say a few words upon the application of the secret, a family misfortune, or an hereditary statistical method to subjects of this kind. disease. If a criminal could be convicted It is scarcely possible to exaggerate the ad-only upon the evidence of himself or his nearvantages which science, and especially bio- est relations, what would be the value of the logical science, has derived from the use of statistics of crime? this method; but just in proportion to the benefit which accrues from the right use of any method, and to the consequent confidence which its application inspires, is the mischief which it can produce if misapplied, and the

France
Corsica
Alps

Canton Berne

These would form grave objections to any argument from statistics in a case such as that before us, and would justify us in questioning a conclusion founded exclusively upon them, even if the statistics themselves were

irreproachable. Whether they are so or not | Breeders know well enough that the produce in the present instance, we shall proceed of two thoroughbred shorthorns, with whose next to inquire. In so doing we must beg pedigree they are well acquainted, will neiour readers to bear in mind the purpose for which the statistics are brought forward. Their authors are all agreed that close breeding whether in man or beast, tends of necessity to produce" degeneracy" in some form or another and this by some unexplained and apparently inexplicable law, quite apart from and independent of those ordinary laws of inheritance, by the experience of whose action we are made aware that the diseases and peculiarities of the parent descend to his offspring, and this the more certainly if both the parents are similarly affected; and they present their several sets of statistics with the object of substantiating this view.

It is impossible not to be struck with the vague use of terms by all writers who support this side of the question. They never seem able to escape as it were from the tyranny of their own phraseology, and appear to suppose that when they have introduced a long Latin word, with a perfectly indefinite meaning, they have gone a long way towards explaining a complicated series of facts. What is really meant by "deterioration" or "degeneracy"? Every variation from an original type, not to mention every disease, might, we suppose, be spoken of as degeneracy. Thus adopting the hypothesis of the unity of the human race, if the first man was white, the black races would be degenerate, and vice versû; and if he was intermediate in color, like the Arab or the Brahmin, then would black and white both equally be degenerate. No one ever doubted the potent influence of close breeding in developing and perpetuating an accidental variety-it is indeed the one only means by which this can be done; and similarly, no one doubts that, given a degeneracy of any kind—a disease or a morbid tendency, already existing, close breeding will tend to develop and perpetuate it in exact proportion to the degree in which it is close. These are merely instances of the operation of the ordinary and well-known laws of inheritance, simple deductions from the time-honored generalization expressed in homely phrase "like breeds like;" and they are intelligible just in the same degree as are any other phenomena of nature which are referred to a general expression, which is for the existing state of science an ultimate fact.

ther be a half-bred Alderny calf nor any other mongrel. But such facts as these are far too simple and well established to satisfy those writers who wish us to believe that if only the progenitors in this example be brother and sister, the produce might vary in the remarkable manner suggested. In the case before us, moreover, the most various and apparently unconnected forms of degeneracy are all attributed to the same cause. Exactly as a Scotch peasant puts every phenomenon of nature for which he is unable to render a reason, to the account of Sir William Wallace or the devil, so do these writers attribute every conceivable imperfection existing in the offspring of parents related in blood to the fact of consanguinity alone. Each observer, it is true, puts some one defect prominently forward, but in each case it is a different one.

The qualities of offspring at birth may be said to be the resultant of the reaction of the sum of those of the two parents upon one another, together with the modifications superinduced upon them by external circumstances. Now, as the antecedents upon which the condition of any offspring depends are thus extremely complicated, it is clear that nothing less than a very large and very unequivocal experience can justify us in asserting that, in a particular case, this, that, or the other phenomenon in the offspring is the result of this, that, or the other individual antecedent in the parents. Such experience in many instances we do possess. Hereditary gout and hereditary insanity are as clearly traceable through many generations in the families in which they are inherent as is the succession to the family estate, and very often much more so. They do not pass upon every member of such families for many reasons, some of which we know, or are apt to think we know—such as emigration, change of external circumstances, habits of fe, or even social position, and still more, the influence of successive intermarriages; but all this notwithstanding, the fact remains, that such defects or peculiarities, once acquired, are, as a rule, transmitted to the offspring; and if the writers of whom we are speaking had contented themselves with showing that the marriages of blood relations

are more likely, cæteris paribus, to produce is doubtless far too narrow to be rigidly apunhealthy offspring than others where an he- plied in investigations into the phenomena of reditary taint exists, they would have made nature; yet we cannot but look suspiciously an assertion which, though neither very at an alleged cause which fails to conform novel nor very interesting, could not well to the definition in every single particular. have been disputed. But what they really In the case before us we all know perfectly have asserted is something far different from well that the five principal consequences here this. It is substantially, that if two persons alleged to follow upon consanguineous marmarry, being related in blood, even at so dis-riages-viz., sterility, mutism, idiocy, detant a degree as that of second cousins, their formity, and scrofula-all occur in children offspring will, as a rule, be degenerate, or when no such marriage has been contracted will themselves produce degenerate descend-by the parents, and are all absent far more ants. The following remarks by another often than present when it has. The attempt writer are quoted by Dr. Devay, and adopted to account for them all by the same cause reby him as accurately representing his own minds us of nothing so much as the similar view. (Devay, 2d ed., p. 246.) attempt to explain all geological phenomena as the effects of the Noachian deluge, and can only lead to physiological absurdities, as that unlucky hypothesis did to geological. Moreover, in all but one of these cases we know of other well-established causes upon which the unhappy results are often found to depend, and unless it can be shown that these are excluded in the instance before us, we are not at liberty to introduce a new cause of which nothing is certainly known. This brings us (2) in the second place to the consideration of how far the facts adduced can be explained by the known laws of inheritance. There is a phenomenon well known to breed

"Ce qu'on reproche aux mariages consanguines ce n'est pas, dit le docteur Dechambre, de perpetuer dans les familles, par le moyen des alliances, les maladies susceptibles de transmission héréditaire, en certaines formes de tempérament, en certaines prédispositions organiques, comme l'étroitesse de la poitrine, ou quelque autre vice de conformation. Il est manifeste que le condition de la consanguinité en soi n'ajoute rien aux chances d'hérédité morbide, lesquelles dépendant de la santé des conjoints et de celle de leurs ascendants reciproques, ont la même source dans toute espèce de mariage. On accuse les alliances entre parents de même souche d'amener de créer par le seul fait de non renouvellement de sang, une cause spécial de dégra-ers of animals, and frequently observed also dation organique, fatale à la propagation de l'espèce."

among mankind, which has been recognized by physiologists under the name of atavism. By atavism is meant a tendency, the laws of whose action are at present quite unknown to us, on the part of offspring, to revert to some more or less ancestral type. Instances are not far to seek, and are familiar to many even who have not gone further than to remark the phenomenon itself. It is no uncommon thing to find a child born who grows up with but little resemblance to his immediate parents, but bearing a strong and remarkable likeness to some grandfather, or great-uncle, or other even more distant ancestor. This is a fact of common experience, nor is the likeness confined to figure or features, for similarities of disposition and temper, peculiarities both of mind and body, and even diseases, are found to descend in

The questions, then, which we have to examine are as follows: 1. Is such a view as the above borne out by the facts which these writers have adduced in support of it? 2. Cannot these facts be equally well explained by the action of the ordinary laws of inheritance? and 3, Are there not other facts left out of view by these writers, which are not only left unexplained by their doctrine, but are quite irreconcilable with it? 1. The first reflection which occurs to a reader on looking at the statistics we have quoted, is, as we noticed above, the extreme diversity of the effects which are in them assigned to one and the same cause, and that, too, in cases in which the antecedents and consequents are many in number, and consist of various elements, some known and more unknown, the same irregular and apparently unaccomplicated and involved among themselves in countable manner. Gout, one of the most every variety of combination. The old school hereditary maladies, has even been supposed definition of an efficient cause, " præsens ef- habitually to miss each alternate generation, fectum facit, mutatum mutat, sublatum tollit," | and fall upon the next beyond. These things,

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