The Age of Exploration: Chapter 2, Exercise 2 — Possible Solution
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TIMELINE
About July 1487: Dias departs with three vessels (approximate).
4 Feb 1488: Mossel Bay reached.
12 Mar 1488: furthest point, near the Boesmans River mouth.
8 Jul 1497: da Gama leaves Lisbon.
Nov 1497: rounds the Cape of Good Hope.
24 Apr 1498: leaves Malindi.
20 May 1498: reaches Calicut.
Late Aug or early Sep 1499: returns to Lisbon (approximate).

APPROXIMATE
Dias's departure ("around July 1487"), da Gama's rounding (only "November")
and his return date.