When the Moon Wanes, Don’t Start Anything

In this post, we delve into a specific voyage undertaken by the ship “São Pantaleão” in 1596, sailing from Kochi to Lisbon, under the skilled guidance of the pilot Gaspar Ferreira Reimão (fl. 1612). With thirty years of experience navigating the India Run and playing various roles, from second pilot to pilot-major, Reimão meticulously recorded daily life aboard his ship, including measurements, annotations about the magnetic needle’s variation, and astronomical observations. One intriguing aspect to explore is the moon’s role during this voyage.

Reimão’s logbook contains references to nearly every phase of the moon, including what is called “conjunção da lua” (conjunction of the moon) in Portuguese. This refers to the moment when sunlight hits only the part of the moon that is hidden from human view (“new moon”). However, it’s worth noting that in the 16th century mariner jargon, the term “conjunction” could refer to any moon phase. Additionally, the phases of the moon were and are perceived differently in the northern and southern hemispheres, a significant factor for a long-distance voyage.

The majority of the pilot’s textual references to the moon had negative connotations, as they often reflected adverse meteorological conditions. For instance, leaving the Maldives on the 28th of January, the weather worsened, and Reimão explicitly attributed it to the new moon’s weakness, leading to relentless heavy rainfall. The pilot used expressions like “we were rotting with water” (“andamos podres com água”), “new moon, bad moon” (“lua nova, má lua”), and “never-ending rainfall” (“tanta infinda chuva”). On February 24th, a month later, while near the Cargados Carajol Shoals (or Saint Brandon) still in the Indian Ocean, the moon’s appearence coincided again with deteriorating weather, characterized by heavy downpours and strong south winds. Near Cape Agulhas on the 20th of March, Reimão encountered what he considered the worst of all possible moon conjunctions, with waning moon, contrary winds, and frequent lightning flashes signaling severe storms (“é quarteirão de minguante… é conjunção [de lua] que eu tenho por pior que todas a que tem a lua”). In the explanation of the phenomena, he did not forget to add that these signs were exactly the same that “mathematicians declare”. Approaching Saint Helena Island in Atlantic waters on the 5th of April, Reimão called the moon “lua chorosa” (“the weeping moon”), associated with atmospheric vapor and westerly winds. The personification of the moon was the beginning of a series of references. The continuous changes in winds and rough seas caused by this moon (“trabalhosa”,“malíssima”, “Lua do Sueste” (Southeast Moon)) brought additional challenges to the navigation. The pilot complained categorically: “This moon has me tired and dead” (“traz-me cansado e morto esta lua”), indicating that the west winds had not changed for twenty-five days, and the southeast winds had not entered; instead, a marine waterspout was produced. Not by chance, the pilot made mention of the presence of wandering albatross (“mangas-de-veludo”), sea birds also known nowadays as storm petrels.

The moon’s influence on navigation compelled pilots like Reimão to wait for the right moon (“esperando a lua que será amanhã”) and favourable travel conditions to continue or begin their voyage. Gaspar Ferreira Reimão’s sailing directions, published in 1612, reveal his navigational experience, including practical reccomendations related to the better moon’s conjunction. The moon’s impact on the voyage of “São Pantaleão” provides valuable insights into oceanic practices and the challenges faced by skilled pilots like Reimão. His numerous references to the moon highlight the richness of maritime technical documents, encompassing climate, global wind patterns, ornithology, tides, astrology, and science at sea, while also resonating with a poweful proverbial cultural heritage. In fact, the timeless Portuguese proverb seems to echo: “When the Moon wanes, don’t start anything” (Quando a Lua minguar, não deves começar). [Luana Giurgevich]