Interestingly, in earlier times, when the Pacific was dominated and sailed by the Spanish Empire, it was reckoned to have a noticeably shorter width. According to the book The Secret Voyage of Sir Francis Drake by Samuel Bawlf;
"..the Spanish continued to understate the breadth of the Pacific by thousands of miles, America was generally depicted as being joined to Asia somewhere to the north."Stating elsewhere in the book;
"Soon after he succeeded to the throne of Spain, King Philip began to take an interest in the potential of his Philippine Islands. Under the Treaty of Tordesillas the islands, like the Moluccas, were actually located in the Portuguese hemisphere. In the absence of any agreed method of determining the eastern line separating the two empires, however, its position was disputed. To support his claim to the islands, Philip had his cartographers produce maps that understated the sailing distance across the Pacific, and argued that the line of demarcation actually cut through the Strait of Malacca 1,000 miles farther west."It's worth noting that the Spanish were actually making frequent sea journeys between South America and their dominions in Asia at this time.
The Pacific Ocean is also the location of the International Date Line - this is an imaginary and somewhat arbitrary line running north to south that demarcates the change from one calendar day to the next. Right up until the 19th century the Philippine Islands found themselves on the "wrong" side of this line and consequently a day behind their Asian neighbours in the region. A legacy of their Spanish rule.
The following map depicting the line illustrates this - though the map, from the 1888 Meyers Konversations-Lexikon, was erroneous at its time of publication as the Philippines had shifted to the west side of the line in 1845.
Next Up: EARTH HOAX; Arctic of the East