As was often true when preparing a paper from research and field material, Jed found that one tiny, apparently insignificant bit of information could make the difference. The secret, though, he had lectured his students, was without the effort required to gather background material, that one additional fact was worthless.

Jed was aware that 13% of the people of the Republic of Panama were of Negroid descent (Mestizo 70%, pure Spanish blood 10%) and that in Panama City, population 439,310, there were 27 licensed gambling casinos. If the racial proportion of the country was the same for the city, and if the typical tropical climate ratio for male/female applied —women outnumber men by 7.6%— there were approximately 26,385 Negroid males of all ages in Panama City. Factoring that figure with the mean numbers of demographic studies of Central America for the category of adult male, 35 to 60 years of age, Jed reasoned that B. J. Rosenbaum was one of only 6,596 individuals.

Narrowing this profile further, the anthropologist made a mental note of the characteristics which would distinguish a semi-professional gambler. Most likely, Rosenbaum had short, blunt fingernails to facilitate the handling of cards, though one, the index digit, would be long and sharp for use as a marking device. His clothing would be neutral. Gamblers tended to make quality purchases after an easy win, but avoided flamboyancy that might attract unwanted attention.

The bit of trivia from Jed's homework that made the difference in his search was that roughly half of the Panamanian blacks were descendants of workers brought in from the British West Indies to help dig the canal. They spoke English.

Using this fact Jed adopted the technique of approaching possible individuals in casinos from behind and asking in a quiet voice, "Black Jack?"

Those who didn't even seem to hear could be assumed to be descendants from early Spanish Colonial era slaves. Panama was one locale in the Western Hemisphere where importing African workers did not work out as planned. The jungle habitat was too similar to the home of the reluctant immigrants to act as prison walls, as was a Maryland snowstorm. Many of the great-great-grandchildren of escaped slaves who had disappeared into the convenient and sustaining lush vegetation were just now emerging from the forest. Their language, an old form of trade route Spanish, was still under the influence of sounds similar to that of the Ibos, Hassu, and other tribes of Africa's slave coast. "Blackjack," was just not one of their everyday expressions.