It seems, and it is, a colossal task to change average human nature one iota. Yet in the light of modern eugenics we could make a new human race in a hundred years if only people in positions of power and influence would wake up to the paramount importance of what eugenics means. And this could be done quietly and simply without violence to existing ideas of what is right and proper. It could be done by segregation of the sexes for defectives, feeble-minded, idiots, epileptics, insane, etc. By this kind of isolation, we can save the blood stream of our race from a tremendous amount of needless contamination. And it is being done. The growing tendency to put defectives in institutions, though originally with no such object, will have the effect of reducing the transmission of defects, especially when it is recognized that the sexes must be separated and that the inmates should be kept at the institution through the reproductive period of life.
Sterilization is also a means which may be advantageously applied in extreme cases. Sensible marriage laws if backed by an enlightened public opinion can add much.
It looks like this book was the source of the much-quoted story about the descendants of Jonathan Edwards:
Few people have any idea, unless they have looked into the pedigrees of some of these people, what awful contamination can be saved the race by a wise application of eugenics. There is a family called "the Jukes," all descended from a thriftless fisherman, born in 1720. About twelve hundred of these descendants have been traced in 75 years. Of these, 310 were professional paupers who spent an aggregate of 2,300 years in poorhouses, 50 were prostitutes, 7 murderers, 60 habitual thieves and 130 common criminals. Dugdale, who compiled these facts, estimated that the "Juke" family cost the Government over $1,000 for each member of the family. Similarly the "Tribe of Ishmael," numbering 1,692 individuals in six generations, has produced 121 known prostitutes and has bred hundreds of petty thieves, vagrants and murderers.  Compare the descendants of that family with the descendants of Jonathan Edwards, who was born in the same period (1 703) and who has had about the same number of descendants (1,394 traced up to 1900). Out of those descendants, something like half have been public men or men of great distinction and good influence in the world; 295 were college graduates, about 100 were clergymen or missionaries, over 100 were lawyers, 80 held public office, 75 were officers in the army or navy, 60 were eminent writers, 30 were judges, 13 were college presidents.
Locating this story in Fisher's context horrifies me. I'd like to know if Fisher was quoting someone else, or if the Edwards narrative was put together (researched?) to suit Fisher's conclusions.