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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 We turn now from the consideration of the more natural, especially in an age when men were much more open to theological than spirit in which inquiries into our present physiological considerations, than that they subject have been undertaken, and proceed to should attribute any ill effect which might give a succinct account of the facts and arguseem to follow from such unions to the special ments which have been brought forward on intervention of Providence. Such ill effects both sides of the question, that our reader would be marked and noticed whenever they may have an opportunity of seeing what real occurred, and would soon become proverbial; value belongs to them, and to which side the and when, in a later age, men began to pay balance of the evidence inclines. This evimore attention to the breeding of animals, dence is derived from two distinct sources, and found that excessively close breeding which differ in their subject-matter, in the seemed, in some cases, to produce similar results, they would be led to establish a false method by which they can be investigated, analogy between the two cases, and to infer and in the degree of certitude which attaches the existence of a law of nature which close to them as far as they severally go, no less breeding and consanguineous marriages equal than in the conclusion to which they lead. ly infringed.
These are, 1, experience derived from the Something like this I conceive to be the true history of the common opinion upon this study of mankind by means of recorded obsubject, an opinion, which, as far as I can
servation and statistics ; and 2, that drawn discover, rests on no satisfactory record of from the study of the lower animals and even observed facts."
of plants, which admits of being brought to
the test of strict experiment as well as of obWe are induced to insist the more strongly servation. The former of these methods has upon this aspect of the question because the been pursued with much diligence by Dr. works even of modern and professedly scien- Bemiss, MM. Boudin, Devay, and others. tific writers bear witness both to the univer- We give a short summary of the results arsality of this popular prejudice, and to the rived at by these observers, in order that our probability of its theological or rather ecclesi- readers may be able at a glance to compreastical origin. Thus Niebuhr * speaks of the hend the several points to which we shall Ptolemies, whose history certainly affords the have to direct their attention. most striking instance on record of close
Dr. BEMISS. DR. HOWE. DR. DEVAY. breeding in the human race, as degenerate
17 both in body and soul. He seems to forget Fruitful that their dynasty continued for some three Sterile hundred
years, and that the history of Cleo- Total Children 192 patra, the last sovereign, though not the last This gives in Dr. Bemiss's cases an average descendant of their line, is certainly not that number of 5.6 children to each marriage; in of a person, in any intelligible sense of the Dr. Howe’s 5.58 to each. The average numwords, degenerate both in body and mind. ber of births to each marriage in England But the most remarkable instance is af- was recently 4.5. Of the 192 children born, forded by Dr. Devay, who, while writing es- 58 died in early life, and 134 reached“ mapecially on this subject in his work on Hy- turity;" i.e., the number of early deaths giene, which he professes to treat scientifi- was as 1 to 3.3. The average of deaths uncally, occupies no small portion of the two der 5 years old, as stated by Dr. West, is 1 chapters devoted to it with a long citation of to 3. It is thus clear that while the fertility fathers and doctors of the Church, from St. of these marriages was much above the averAugustine down to the contemporary Arch
age, the infant mortality in their offspring bishop of Tours. Truly it might be consid- was slightly below. In Dr. Devay's cases ered a rare treat for orthodox Frenchmen in the total number of children is not given, and these skeptical days to find such authorities therefore no calculation on the point can be polled to settle a scientific question, were it made. not that a few recent events, such as the late
In consequence of the different principles *“ Lectures on Ancient History." Vol. iii. p. upon which these authors have arranged 471.
their statistics, it is impossible to exhibit
Not stated . Not stated
22 Not stated.
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 DR. BEMISS.
been applied to elucidate facts in patholIn 75 Cases of Disease. In 58 Cases of Dis. ogy, such as the probability of death from a Scrofula and Consumption 38 or •506 12 or.207 particular disease at a particular time of life. Epilepsy and Spasmodic Dis. 12 or •16
Often, too, when the will of man is an eleDeafness
2 or.026 lor.017 Idiotcy.
4 or 053 44 or.758 ment in the calculation, but when that will Deformity.
2 or 026 0
can be shown to be swayed by conflicting moFrom the loose form in which Dr. Devay's tives, the comparative power of which it is results are stated, we are able to contrast his impossible to guage, a judicious application statement with the above in one point only, of the statistical method, if only the number namely, that of deformity, which appears in of instances collected be sufficiently large, 27 out of 52 cases, or •519 as against ·026 in may enable us to arrive at a conclusion at one of the other cases, and 0 in the other. least approximately true. But it does not
M. Boudin's statistics are of a different follow from the full admission of all this, character and on a much larger scale. He that the same method can be followed in takes merely the one defect of deaf-mutism, cases such as that before us, and with a view and finds 1st, That while consanguineous to ascertain the causes as well as the circummarriages are 2 per cent. of all marriages in stances of the phenomena to which it is apFrance, the number of deaf-mutes born of plied. Thus, it may be true that we can arsuch marriages are, to all deaf-mutes,
rive at the number of murders which will be In Lyons
committed in a population of a certain extent
25 per cent. In Paris
28 per cent.
in a given time, but it does not follow that In Bordeaux
we can also tell what is the cause of all these 30 per cent.
murders, or that they all depend upon the He finds further : 2d, that the danger of deaf
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
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 in
pends upon the truth of a number of family France
6 in 10,000.
histories. These are all matters of testimony, Corsica
14 in 10,000. and the motives to falsification thereof lie all Alps
23 in 10,000. on the same side. There is, perhaps, as most Canton Berne. 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 These would form grave objections to any benefit which accrues from the right use of argument from statistics in a case such as any method, and to the consequent confidence that before us, and would justify us in queswhich its application inspires, is the mischief tioning a conclusion founded exclusively upon which it can produce if misapplied, and the 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 ther be a half-bred Alderny calf nor
other which the statistics are brought forward. mongrel. But such facts as these are far Their authors are all agreed that close breed- too simple and well established to satisfy ing whether in man or beast, tends of neces- those writers who wish us to believe that if sity to produce “ degeneracy” in some form only the progenitors in this example be brothor another : and this by some unexplained er and sister, the produce might vary in the and apparently inexplicable law, quite apart remarkable manner suggested. In the case from and independent of those ordinary laws before us, moreover, the most various and apof inheritance, by the experience of whose parently unconnected forms of degeneracy are action we are made aware that the diseases all attributed to the same cause. Exactly as and peculiarities of the parent descend to his a Scotch peasant puts every phenomenon of offspring, and this the more certainly if both nature for which he is unable to render a reathe parents are similarly affected ; and they son, to the account of Sir William Wallace present their several sets of statistics with or the devil, so do these writers attribute evthe object of substantiating this view. ery conceivable imperfection existing in the
It is impossible not to be struck with the offspring of parents related in blood to the vague use of terms by all writers who sup- fact of consanguinity alone. Each observer, port this side of the question. They never it is true, puts some one defect prominently seem able to escape as it were from the tyr- forward, but in each case it is a different anny of their own phraseology, and appear one. to
suppose that when they have introduced a The qualities of offspring at birth may be long Latin word, with a perfectly indefinite said to be the resultant of the reaction of the meaning, they have gone a long way towards sum of those of the two parents upon one explaining a complicated series of facts. another, together with the niodifications suWhat is really meant by “deterioration” or perinduced upon them by external circum
degeneracy”? Every variation from an stances. Now, as the antecedents upon original type, not to mention every disease, which the condition of any offspring depends might, we suppose, be spoken of as degener- are thus extremely complicated, it is clear acy. Thus adopting the hypothesis of the that nothing less than a very large and very unity of the human race, if the first man was unequivocal experience can justify us in aswhite, the black races would be degenerate, serting that, in a particular case, this, that, and vice versû; and if he was intermediate in or the other phenomenon in the offspring is color, like the Arab or the Brahmin, then the result of this, that, or the other individwould black and white both equally be de- ual antecedent in the parents. Such experigenerate. No one ever doubted the potent ence in many instances we do possess. Heinfluence of close breeding in developing and reditary gout and hereditary insanity are as perpetuating an accidental variety—it is in- clearly traceable through many generations deed the one only means by which this can in the families in which they are inherent be done; and similarly, no one doubts that, as is the succession to the family estate, and given a degeneracy of any kind—a disease or very often much more so. They do not pass a morbid tendency, already existing, close upon every member of such families for many breeding will tend to develop and perpetuate reasons, some of which we know, or are apt it in exact prorortion to the degree in which to think we know-such as emigration, it is close. These are merely instances of the change of external circumstances, habits of operation of the ordinary and well-known kife, or even social position, and still more, laws of inheritance, simple deductions from the influence of successive intermarriages ; the time-honored generalization expressed in but all this notwithstanding, the fact rehomely phrase like breeds like ; " and they mains, that such defects or peculiarities, once are intelligible just in the same degree as are acquired, are, as a rule, transmitted to the any other phenomena of nature which are re- offspring; and if the writers of whom we are ferred to a general expression, which is for speaking had contented themselves with the existing state of science an ultimate fact. 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 “ Ce qu’on reproche aux mariages con- as the effects of the Noachian deluge, and sanguines ce n'est pas, dit le docteur De- can only lead to physiological absurdities, as chambre, de perpetuer dans les familles, par that unlucky hypothesis did to geological. le moyen des alliances, les maladies suscepti- Moreover, in all but one of these cases we bles de transmission héréditaire, en certaines know of other well-established causes upon formes de temperament, en certaines prédis- which the unhappy results are often found positions organiques, comme l'étroitesse de la poitrine, ou quelque autre vice de conforto depend, and unless it can be shown that mation. Il est manifeste que le condition de la these are excluded in the instance before us, consanguinité en soi n'ajoute rien aux chances we are not at liberty to introduce a new cause d'hérédité morbide, lesquelles dépendant de of which nothing is certainly known. This la santé des conjoints et de celle de leurs as- brings us (2) in the second place to the concendants reciproques, ont la même source sideration of how far the facts adduced can be dans toute espèce de mariage. On accu se les alliances entre parents de même souche explained by the known laws of inheritance. d'amener de créer par le seul fait de non renou
There is a phenomenon well known to breedvellement de sang, une cause spécial de dégra- ers of animals, and frequently observed also dation organique, fatale à la propagation de among mankind, which has been recognized l'espèce.
by physiologists under the name of atavism. The questions, then, which we have to ex- By atavism is meant a tendency, the laws of amine are as follows: 1. Is such a view as whose action are at present quite unknown the above borne out by the facts which these to us, on the part of offspring, to revert to writers have adduced in support of it? 2. some more or less ancestral type. Instances Cannot these facts be equally well explained are not far to seek, and are familiar to many by the action of the ordinary laws of inheri- even who have not gone further than to retance ? and 3, Are there not other facts left mark the phenomenon itself. It is no unout of view by these writers, which are not common thing to find a child born who grows only left unexplained by their doctrine, but up with but little resemblance to his immeare quite irreconcilable with it? 1. The diate parents, but bearing a strong and refirst reflection which occurs to a reader on markable likeness to some grandfather, or looking at the statistics we have quoted, is, great-uncle, or other even more distant anas we noticed above, the extreme diversity of cestor. This is a fact of common experithe effects which are in them assigned to one ence, nor is the likeness confined to figure or and the same cause, and that, too, in cases features, for similarities of disposition and in which the antecedents and consequents temper, peculiarities both of mind and body, are many in number, and consist of various and even diseases, are found to descend in 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,
we repeat, are known to happen among man- to the whole number of marriages, we feel kind, but from the length of human life, as that we are on different ground. Such ancompared with that of the domestic animals, nouncements cannot fail to produce in most it is among the latter that we find, as we men's minds a strong apprehension, at the might expect, that they have been most fre- very least, that the two phenomena which he quently observed, and in fact, the tendency is laboring to connect have, after all, some to atavism is, we believe, habitually recog- close mutual interdependence. On the other nized and allowed for by the breeders of cat- hand, when we fairly consider the difficulties, tle. But though the fact is undoubted, no some of which we have just seen, which lie man can point out beforehand the individual in the way of demonstrating that the defect case in which this reversion to the old type, is not in many cases inherited, the extremely this relapse, as we may call it, will take complicated character of the phenomena with place, and many a time, doubtless, has its which we have to deal, and, above all, the sudden occurrence frustrated the hopes of fact that on M. Boudin's own showing, the the breeder and wasted his labor and care. alleged cause is absent in an absolute majorNow, if the known fact of atavism is fairly ity of the cases in which the effect is seen to considered, it at once affords an answer to follow, we are once again compelled to susthe objection of M. Boudin and Dr. Devay, pend our judgment, and to look further for that the various defects and diseases, the new facts before we can arrive at a conclustatistics of which they have collected, can- sion. not be traced to the parents of those subject So far, then, we might conclude that the to them, and cannot therefore be looked upon imperfect condition of our knowledge of the as hereditary. The commonest acquaintance phenomena of inheritance, including in that with the ordinary conditions of human life term variation and atavism, precludes our will enable any one to see that it is impossi- coming to any decision upon the subject, but ble for a medical man to investigate the fam- that the general consent of mankind, toily histories of any fifty of his patients, so gether with the positive evidence which has far as to arrive at a clear notion of what has been given, is sufficient at any rate to arouse been the condition of health of even the four in our minds some misgivings lest the “ law grandparents whom nature apportions to us of nature” which Dr. Devay and others conall; and yet, without this, how can he pro- tend for, should really be found to exist : but nounce with any certainty that a particular before we can fairly yield, even to this exdisease or infirmity is not inherited? It may tent, to the arguments of these authors, we be urged, no doubt with some force, that to must provide an answer to the third query, bring into the discussion a phenomenon of viz., (3) Whether there are not some facts which we know so little as we do of atavism which are quite irreconcilable with the theory is to appeal not to our knowledge, but to our in question ? Now, in the case of the huignorance ; but the same is true, and true in man race, the difficulty of obtaining trusta far higher degree, of consanguinity itself. worthy evidence is so great, that we should
So far as we have gone at present, it may despair of ever attaining even to an approxibe said that the two sides of the argument mation to the truth, did we depend on it are on the whole pretty evenly balanced. alone. It consists almost exclusively of the The statistics of MM. Bemiss, Home, and published opinions of certain observers, more Devay may be left to answer one another, or less competent, as to the hygienic condiand even if they be considered to fail in do- tion of certain small communities who from ing so, the number of instances collected by their isolated position are either supposed or these gentlemen is insufficient to afford more known to intermarry frequently among themthan the feeblest presumption in favor of selves ; and their opinions are found to be as their conclusion. But when M. Boudin comes contradictory in character as they are scanty forward, counting his instances by thousands, in number. Fortunately, however, the eviand tells us that in France the number of dence derived from the breeding of animals, deaf-mutes who are descendants of consan- and the record of that evidence preserved in guineous marriages is from ten to fifteen the “ Herd-book" and the “Stud-book,” is times what it ought to be when compared clear and decisive upon this point. Mr. J. with the proportion which such unions bear H. Walsh, well known, under the nom-de