"Their Hindoo complexion, and their very imperfect resemblance to the European Jews, indicate that they have been detached from the parent stock, in Judea, many ages before the Jews in the west, and that there have been intermarriages with families not Israelitish. — I had heard that those tribes, which had passed the Indus, had assimilated so much to the customs and habits of the countries in which they live, that they sometimes may be seen by a traveller without being recognised as Jews. In the interior towns of Malabar, I was not always able to distinguish the Jew from the Hindoo. I hence perceived how easy it may be to mistake the tribes of Jewish descent among the Afghans and other nations, in the northern parts of Hindostan. The white Jews look upon the black Jews as an inferior race, and as not of pure caste, which plainly demonstrates that they do not spring from a common stock in India."
January 1, 1970
https://en.wikiquote.org/wiki/History_of_the_Jews_in_India