I found a book on East Africa. Only there was no mention of pyramids. In fact, the Luos merited only a short paragraph. Nilote, it turned out, described a number of nomadic tribes that had originated in the Sudan along the White Nile, far south of the Egyptian empires. The Luo raised cattle and lived in mud huts and ate corn meal and yams and something called millet. Their traditional costume was a leather thong across the crotch. I left the book open-faced on a table and walked out without thanking the librarian.