The Search for the Manila Galleon Log Books

Abstract

Spanish merchant ships, called Manila Galleons, made the round-trip between the Philippine Islands and the ports on the west coast of what is now Mexico, almost every year for the 250-yr period between 1565 and 1815. The log books of these galleons contained weather information which was thought to be of value in the study of the historical climatology of the tropical and mid-latitude areas of the Pacific Ocean. A search was made for the log books of the Manila Galleons to determine how many are still extant and the nature of the weather data that they contained. The search was made with the assistance of expert historians and paleographers who ware experienced in searching archives where the log books wore thought to be on file. The following archives were searched: the Museo Naval in Madrid, Spain; the Archivo General do Simancas in Simancas, Spain; Archiyo De lndias in Seville, Spain; Archivo General do la Nación in Mexico City, Mexico; and the National Archives in Manila, The Philippine Islands. Only sixteen log books were on file In the archives in Madrid and Seville. All of the logs that wore found ware from the period between 1766 and 1808. The inevitable conclusions that were reached were that log books for some of the earlier voyages may never have been written and that most of the log books that were written were either physically lost or were lost due to the ravages of time, moisture, insects or war.