difficulty number 4 answers on 1st july

Caleb Smathers was walking home from the market with three nice ripe oranges, when he was faced with a problem. On the footbridge which he had to cross there was a sign announcing that the bridge's capacity was two hundred pounds. Caleb himself weighed a hundred ninety-six pounds and the oranges weighed two pounds each. What to do. He could, of course, make two trips, but a moment's reflection enabled him to figure out a way of getting himself and his three oranges across safely in one trip. How did he do it?