2057. Record of Family Faculties. ancestry up to their eight great-grandparents inclusive, will be equipped with almost as much hereditary information as they can need. But when an alien element of race or disease has been introduced into the family, its influence lasts longer; so that a dash of Hebrew or even of Huguenot blood may be traced far beyond the great-grandchildren, and has often been found to exercise a notable and valuable influence upon numerous descendants. There is, also, something of much importance to be added about the brothers and sisters, uncles and aunts, and great-uncles and great-aunts of the two parents. Brothers and sisters are alike in blood, but it commonly happens that one of them exhibits some faculty in a conspicuous degree, which exists only in a latent form in another, and which the latter is perhaps equally capable of transmitting to his children. Therefore records of the faculties of the brothers and sisters of the direct ancestors are of great value in disclosing hidden characteristics. The biological history of half-blood relatives is of secondary importance. Consequently, I have left no place for cousins in this book, though, of course, the writer in it can interleave fresh pages to receive what entries he pleases. If the custom of recording family faculties should become common, stores of information will be called into existence from which future inquirers into heredity may have the good fortune to draw copious supplies. I have found great willingness among correspondents to impart family information, when they are assured that it will be used for statistical purposes only, but the comprehensive family information which is now especially needed for scientific study and which, it is hoped, these records will collect, has never yet been brought together, and therefore does not at present admit of being imparted. The advance of the science of heredity is seriously delayed through the want of such data. We do not yet know whether any given group of different faculties which may converge by inheritance upon the same family will blend, neutralize, or intensify one another, nor whether they will be metamorphosed and issue in some new form. Our ignorance is especially great in hereditary maladies, where much alarm undoubtedly exists which inquiry will dispel. It is possible that the different disease tendencies of different ancestors may in some cases neutralize one another, and on the other hand, that some ancestral combinations may be far more hurtful to the descendants 2 [end]