28 - Note on the Marriages of First Cousins

Summary

After I had read my paper on this subject in March last before the Statistical Society, Mr Arthur Browning (a Fellow of the Society) suggested to me another method of determining whether cousin marriages were injurious or not. This method was to discover whether the proportion of offspring of first cousins, amongst persons distinctly above the average, either physically or mentally, was less or greater than the general proportion given by my paper for persons in a similar rank of life.

Mr Browning and I agreed to carry out this scheme together; but we thought it would be well to delay extensive operations until we saw what success was attainable in a more limited inquiry. The results are so very unequal to our expectations that we do not intend to proceed further. The statistics are, however, of some interest as far as they go.

The boating eights, who race at Oxford and Cambridge in May, are a picked body of athletic men. There are twenty boats at Oxford, and thirty at Cambridge, in the “first and second divisions”; and their crews are 400 men, exclusive of coxswains. We accordingly sent circulars to the stroke-oars of these fifty boats, during their preparatory training, begging them to ask the members of their crews whether their parents were first cousins or not. Where there were several brothers rowing in the eight, they were only to be counted as one case; and cases of refusal to answer were also to be marked.