Note 35 — A JOURNAL OF THE FIRST VOYAGE OF VASCO DA GAMA IN 1497-99.

This date, August 18th, is obviously wrong. Deducting the delay of two days, Vasco da Gama spent 95 days on his passage from São Thiago to the Bay of St. Helena, the distance being about 1,170 leagues (4,290 miles), his daily progress amounted to 12 leagues or 45 miles. If the dates in the text were correct, he would have made 12½ leagues daily up to August 18th, and between that date and the 22nd (allowing for the delay) at least 300 leagues (1,010 miles), which is quite impossible. It is evident that the second date is wrong, and instead of “the same month”, we ought perhaps to read “October”. In that case the daily progress, up to October 22nd, would have averaged 10 leagues (34 miles). Thence, to St. Helena Bay, a distance of 370 leagues accomplished in 16 days, the daily progress would have averaged nearly 23 leagues (78 miles). Of course these are merely rough approximations, as the course taken by Vasco da Gama and the incidents of this memorable passage are not known to us. We may mention that modern sailing vessels going from S. Thiago by way of Sierra Leone and Ascension to the Cape, a distance of 5,410 miles, occupy on an average 49½ days on the passage, making thus 110 miles daily (58 in crossing from Sierra Leone to Ascension). A ship going direct (3,770 miles) has performed the passage in 41 days, thus averaging 92 daily. (See Admiral Fitzroy’s “Passage Tables” in the Meteorological Papers published by the Admiralty in 1858.)