When I was twelve years old, the well-known oculist, Dr Barkan of blessed memory, came to examine the eyes of all the children in the School for the Blind at Berkeley. I was the first to be examined, and I remember distinctly every word of the great doctor when, after looking at my eyes, he turned to the superintendent, and said sadly, "Needlessly blind! her eyesight _could_ have been saved." These words made a profound impression upon my childish mind, and as I sat and listened, while child after child was examined, and heard again and again the same remark, "needlessly blind!" I resolved to know more about this eye disease with the very long name, ophthalmia neonatorum, to learn its cause, and see just how it might have been prevented. But we did not hear as much about prevention as we do now, and, although I did not forget the matter, it was many years before I had an opportunity to study it further. When I did, I found that at least one-fourth of the children in schools for the blind in this country were there, just because a simple precaution was not taken at the time of their birth. Five years before I knew there was such a thing as unnecessary blindness (since I had been told I was blind as the result of a severe cold in the eyes), a Belgian doctor, Professor Crede, a famous obstetrician of Leipsic, appalled at the number of children who lost their eyesight within a few days after birth from a virulent eye infection, determined to try the effect of a simple prophylaxis, a two per cent solution of nitrate of silver, dropped in the eyes of every newborn child. The effect of the prophylaxis used in Dr Crede's clinic was marvelous, reducing the number of cases from ten per cent in 1880, to one-fourth of one per cent in 1886.