FRANCIS GALTON LABORATORY FOR NATIONAL EUGENICS EUGENICS LABORATORY MEMOIRS. II. A FIRST STUDY OF THE STATISTICS OF BY DAVID HERON, M.A. SECOND GALTON RESEARCH FELLOW IN NATIONAL EUGENICS LONDON PUBLISHED BY DULAU AND CO., 37, SOHO SQUARE, W. 1907. Some reconstruction of the Francis Galton Laboratory having taken place, it seemed desirable to provide the workers associated with it with a direct channel of publication of their own, in which their more extended memoirs should appear. It is hoped that the present series may be issued at short intervals. Subscribers should notify their intention of taking in the memoirs as they are published to Messrs Dulau & Co. Requests to exchange with similar publications, with archives and journals dealing with demographic and sociological problems, or with census reports should be directed to The Editor, Eugenics Laboratory, University College, Gower Street, London, W.C. A First Study of the Statistics of Insanity and the Inheritance of the Insane Diathesis. BY DAVID HERON, M.A., Galton Research Fellow in National Eugenics, (1) Introductory. It will appear at first sight presumptuous that a layman should venture into a field which has been so much cultivated by the trained medical mind, and where such numerous pitfalls exist for those unacquainted with the various phases of mental disease popularly grouped under the broad term insanity. Even to the layman it may indeed seem imperative that each type of mental disease should be dealt with separately and the problem of inheritance considered for each apart. Undoubtedly this must form the last word on the subject, the final treatment of the "inheritance of insanity" when the data are available. But is the time ripe for any such investigation? May it not be that a broader treatment from the side of popular terminology may be in itself helpful as stimulating the minds of those in charge of the insane to see the question of heredity from another standpoint-that of the statistician? What appears from the statistical side at present so urgent is the need that those who have not only the opportunity but the clinical training necessary for accurate observation, should record their facts in a form in which the trained statistician can apply to them the methods of modern statistics. A careful examination of the Annual Reports of the Asylums of Great Britain and Ireland has led to the conviction that no data at present published would enable the statistician to reach any quantitative results as to the inheritance of any single form of brain disease. Even medical treatises as a rule go no further than stating the percentage of cases in which insanity or some other want of mental balance has been recorded in the family history. As long as we do not know the total number in each class of relatives of the insane person and the exact brain defect from which they have suffered; as long as we do not know the total number of relatives of a random sample of the sane population and the exact forms of neurosis or brain disease from which they too have suffered, any attempt at a full treatment of the "inheritance of insanity" is from the statistical standpoint |