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The navigation of Columbus and its relation to his landfall in Cuba


    Monografias.com

    The navigation of Columbus and its relation to his landfall in cuba

    Most scholars today accept that the first landfall of Columbus in Cuba was in the little port of Bahia Bariay, just west of here. But not too long ago, there was little agreement about Columbus"s route on his first voyage. In particular, there were two such disputes: first, the location of his first landfall in the Bahamas, and second, the location of his first landfall in Cuba.

    The Bahamian landfall problem is too large to cover here in detail. But the Cuban landfall is not only tractable in our available time, it is also appropriate to discuss in this forum. Is Bahia Bariay in fact the correct location of Columbus"s first view of Cuba? And if so, why? To answer this, first let us say a word about primary sources for the historian.

    When he returned to Spain in 1493, Columbus reported to the royal court at Barcelona, and gave his original log to the Sovereigns. Queen Isabel ordered the log to be copied, resulting in the so-called Barcelona Copy.The original has not been seen since, but the Barcelona Copy was returned to Columbus before his second voyage later that year, and remained in his possession until his death in 1506. It then passed into the hands of his heirs, but it too was lost sometime after 1554.

    Before that time, however, much of the contents of the Barcelona Copy was abstracted by Bartolome de Las Casas into the document known as the Diario. This abstraction was part of the research program that eventually led to his massive work, the Historia de las Indias.The Diario remains our primary historical record of the first voyage of Columbus.

    It also is clear that Columbus"s son Fernando had access to the Barcelona Copy when he wrote his biography of the Admiral in 1537. The biography contains a number of details that could only have come from the Admiral himself, and which are absent from the Diario. Further, there is one place where both Fernando and Las Casas quote from the Barcelona Copy, and Fernando"s quote is slightly longer. But on the whole, Fernando"s biography is much less detailed than the Diario of Las Casas. Therefore I will rely primarily on the Diario in evaluating the Cuban landfall.

    A critical question is the accuracy of the details in the Diario, and in particular the accuracy of the navigational data. Clearly, having bad information may be worse than having no information at all. Over the years, the accuracy of Columbus"s navigational records have been challenged by many historians, who are happy to point out its few discrepancies, particularly in the distance measurements. Often, however, these historians usually have some particular position that they wish to assert, such as a theory on the Bahamian landfall. It is certainly true that many advocates of certain Bahamian landfalls have good reason to assert that the Diario is inaccurate, since the Diario does not fit these historians" theories very well.

    But is this perception of an unreliable navigational record really true? Let"s start by looking at one of the most frequently mentioned problems with the log, the famous double bookkeeping.

    First, some background. It is clear that Columbus navigated by a combination of dead reckoning and, when available, by pilotage between visible landmarks. Dead reckoning is simply a distance and direction computation from a known point. His unit of measure was the maritime league, and it is clear from the Diario that each league is comprised of four miles.

    On the westbound passage many of the daily distances in the Diario are given twice, one figure being Columbus's own true figure, and a smaller number which was (according to Las Casas) a falsified number given publicly to allay fears of the crew that they had sailed too far from Spain. But this story has been doubted by many, because most of the crew were experienced mariners in their own right, and they were certainly just as able to determine the distance sailed as was Columbus. In 1983, James E. Kelley Jr. proposed an elegant solution to this problem. Kelley noticed that the true and false numbers tend to cluster around a ratio of 6 to 5. This is quite close to the ratio between the Italian or Geometric league of 2.67 nautical miles, and the Portuguese Maritime league of 3.2 nautical miles. Kelley proposed that Columbus was using the Italian league, while the Spanish sailors were using the Portuguese Maritime League; the double bookkeeping was then simply an artifact of Columbus converting between the two units of measure, although these conversions were sometimes haphazard, and were misunderstood by Las Casas.

    For many years, it had been believed that Columbus used the Roman mile of about 1300 meters, which was then commonly used in Spain. But the Roman Mile has a big problem: the transatlantic distance reported by Columbus would be far too great, by more than 10%, if Columbus used the Roman mile.

    So if Kelley is right, and Columbus was using the Italian Mile and Italian league, this neatly solves the problem of the transatlantic distance, and at the same time, it also solves the problem of the double bookkeeping: Columbus was just converting from one type of league, that he was used to, into another type of league, that his crew was used to.

    For these reasons, the Italian Mile and its associated Italian League are now widely used among historians in North America when evaluating the Diario of Columbus.

    A second important consideration is the effect of ocean currents on the distances reported in the Diario. To find the distance sailed during the day, you must do a calculation based on time and speed. Sailors measured the speed of the ship every hour. In Columbus"s day, they would throw a piece of flotsam over the side, and measure the time it took for the flotsam to pass a measured distance along the ship"s rail. The time is measured using a quick-chant, which forms a mnemonic. Each syllable of the chant stands for a different speed. The exact words to such a chant are part of a lost oral tradition of the sea.

    There are two problems with this method. First, if the ship is going very slowly, the chant may run to the end before the flotsam reaches the aft mark on the rail. Therefore, it is not possible to measure very slow speeds. Second, this method measures the speed of the ship through the water only. If the water itself is moving, there is no way to account for that. This means that if Columbus is sailing with an oceanic current, the speeds and distances he measures will be less than the true distances. And if Columbus is sailing against an oceanic current, the speeds and distances he reports will be greater than the true distances.

    We should also keep in mind that there are actually two kinds of distances that Columbus reports in the Diario: first, distances that he actually sails; and second, distances that he sees by eye. The sailed distances are, we can suppose, actually measured by Columbus, using his familiar dead-reckoning navigation techniques. The sighted distaces are estimates, not measurements, and therefore should be given less credance when evaluating the historical record.

    A third important consideration is the effect of magnetic declination. The directions that Columbus reports in the Diario are based on readings from the ship"s compass. In Columbus"s day, it was not widely known that the compass did not point to true north, and it was not known at all that this variation changed from time to time and from place to place. For that reason, there are few if any measurements of magnetic declination from this period. However, there are a number of indirect measures of magnetic declination that we can gather from very early maps of the region, and from other sources. All of these sources indicate that magnetic variation in the Bahamas and eastern Cuba was somewhat westerly, by perhaps five to seven degrees. The sailing directions given in the Diario are given in compass points, each of which is about eleven degrees. Therefore, the sailing directions given in the Diario should be fairly accurate, with that allowance.

    Given all of this, just how accurate are the navigational directions in the Diario of Columbus? I believe that they are remarkably accurate. Let us take one example from the Bahamas, which will be instructive.

    Columbus visited four major islands in the Bahamas, which we will call island I, Island II, island III, and island IV. There are many theories as to which four islands these really are; but here I will not hesitate to say that Columbus"s most likely route through the Bahamas would indicate that these islands are really the Plana Cays for island I; Crooked and Acklins islands for island II; Long island for island III; and Fortune Island for island IV. All other routes have many more problems that the route just described.

    Columbus said that island II has a coast running north-south for five leagues that faces island I; Island I therefore lies east of island II. The distance from island I to island II he gives twice. First he estimates by eye at seven leagues; but later, after sailing the distance, he gives about five leagues. We should note, however, that Columbus also says that he was sailing against a current on this leg. Therefore, it is reasonable to suppose that the five league distance is an underestimate from the true distance.

    Island II also has a coast running east-west for ten leagues, which Columbus sails along. From the western end of island II, Columbus sails west again to island III, a distance of eight leagues. In this area of the world, the prevailing currents run to the west, so it is likely that Columbus was sailing with a current. This would make the eight league distance an underestimate; and in fact it is, since the true distance from Crooked Island, or island II, to Long Island, or island III, is closer to ten leagues than eight.

    The distance from island III to island IV is more difficult, because Columbus does not tell us this distance directly. But we can deduce it from clues in the log. From island III, Columbus first sails for three hours southeast, and then for another three hours east, to reach island IV. If the speeds of these two legs are the same, as seems reasonable, then the aggregate course he sailed on that day was east-southeast. The actual distance of each of these legs, from Long Island, or Island III, to Fortune Island, or island IV, is seven leagues each, for a total of fourteen. But again, Columbus was sailing in a region of prevailing westerly currents, only this time the currents would be against him. Therefore we can expect that Columbus would have overestimated the distance somewhat. Based on his earlier overestimate of the distance from island II to island III, covering much the same part of the sea, it seems reasonable that Columbus could have overstated the distance by perhaps two leagues, or sixteen leagues.

    Now if we compare this hypothetical map to a real map of these islands, we see that Fortune Island, or island IV, is way too far east on this hypothetical map. This is caused by the two mis-estimated distances between these islands, both caused by the prevailing northwesterly currents in this region. In fact, on the hypothetical map, island IV is only eight leagues from island I, Columbus"s starting point, which is about half the true distance from the Plana Cays to Fortune Island.

    Now here is the remarkable thing. Several weeks later, while sailing north of Cuba, Columbus mentions in the Diario the distance from island IV to island I. And the distance he gives is eight leagues, just the same as we have it mapped here. Therefore, we can be confident that the hypothetical map we have drawn is quite similar to the actual map that Columbus himself drew on his first voyage.

    Further, we can also be quite confident that the procedures we have proposed are in fact correct, and give correct results. If we follow the directions in the Diario, and make appropriate corrections based on our modern knowledge of ocean currents, magnetic variation, and league distance, we are likely to arrive at a correct result.

    Now let us apply what we have learned to the problem of Columbus"s landfall on Cuba. First, let us recap briefly the details of Columbus"s discovery of this island. After leaving island IV, Columbus sailed west again and found a string of islands running north-south, which he called "las islas de arena". (Today we call them the Ragged Islands.) Columbus anchored five leagues off the southernmost island. He does not say in which direction this five leagues is, but he does say that the water is still shallow at that point. And indeed it is; this area is still known today as the Columbus Bank. Unfortunately, the Columbus Bank is rather large, and there is no way to know precisely where on this bank he may have anchored.

    Leaving this anchorage, Columbus then sails 17 leagues south-southwest, and sees the island of Cuba, just before nightfall, in the rain. (This distance is quite correct.) The fleet then "jogs on and off" during the night; that is, they sail back and forth, making no distance, in order to avoid any hazards that may be unseen in the night. On the morning of October 28, 1492, the three ships of Columbus arrive at Cuba, and find "un rio muy hermoso y muy sin peligro de bajas ni de otros inconvenientes." He names this river San Salvador.

    The next day, Columbus sailed west along the coast. After one league, he came to another river, not so large, which he called Rio de la Luna. He continued west from there, for an unknown distance, until he came to a third river, which was very much larger than the others, which he called Rio de Mares. The following day, he went northwest along the coast for another fifteen leagues, and came to a cape which he called Cabo de Palmas. Beyond there, he saw another river which was too shallow to enter, and then a north wind forced him to return to the Rio de Mares on October 31.

    Our first task then is to determine the most likely region along the coast for the landfall on the Cuban coast. We start at Columbus"s previous anchorage, five leagues off the Ragged Islands. From the southernmost of these islands, we can draw a circle five leagues in radius, and determine that Columbus started for Cuba from some point along this arc. We know that he sailed south-southwest by the compass. Now, as we said before, there was a slight westerly variation of the compass, which would have pulled him left of his intended course a little. However, we must also keep in mind that there is an ocean current here, called the Antilles Current, that flows generally northwestward along the north coast of Cuba. And, we also know that Columbus spent all night long jogging off and on, and it seems reasonable to conclude that during these hours, the current would have pulled him westward a little along the coast. So the effect of the magnetic variation is cancelled out by the effect of the current.

    That means that the landfall on the night of October 27 can only have occurred in a very limited region of the coast. The Cuban landfall can only have occurred between Puerto de Samá, in the east, and Puerto de Gibara in the west. Other points cannot be supported by the requirement to sail south-southwest from the anchorage on the Columbus Bank.

    In this region, there are many harbors, inlets, or estuaries which might be the elusive Rio San Salvador. To determine which one is the most likely, let us solve the problem in reverse. We will start with the last harbor of the three Columbus mentions, Rio de Mares. Recall that from the Rio de Mares, Columbus sailed fifteen leagues west along the coast to Cabo Palma, and did not encounter any other harbor. Further, since he was sailing with the prevailing current, it is likely that this fifteen leagues is an underestimate. Now fifteen leagues is forty nautical miles, or more than 70 kilometers -a very long distance. On this part of the coast of Cuba, there is no stretch of coastline that runs for over 70 kilometers without a significant harbor. Therefore, the distance reported by Columbus must be in error. Given what we have learned about Columbus"s navigational records from the Bahamas, it seems most likely that this error may have been caused by currents. In particular, it is not uncommon to see an onshore countercurrent running the opposite direction from the prevailing offshore current. If that happened here, the fifteen leagues reported by Columbus would be an overestimate rather than an underestimate. So what we want to find is a long stretch of coastline without any harbors or other notable features.

    Clearly, the most likely such coastline is that between Puerto Gibara and Puerto Padre. For this reason, it is quite likely that Puerto Gibara is the Rio de Mares of Columbus. Further, Puerto Gibara is quite wide, just as Columbus describes. Puerto Padre is then the river or harbor that Columbus saw beyond Cabo Palma, but was unable to enter. Even more important, just east of Puerto Gibara are a series of small harbors, that seem to roughly match the descriptions given by Columbus.

    Eastward from the Rio de Mares, Columbus describes a small harbor which he calls Rio de la Luna. And eastward from Puerto Gibara, there is such a small river, called today Rio Jururú. It seems quite likely that these two are in fact the same river.

    But now we have a serious problem. Eastward from the Rio de la Luna is the first landfall in Cuba, the Rio San Salvador. There are two important clues about Rio San Salvador: first, it is one league east of Rio de la Luna; and second, it is larger than Rio de la Luna. This is a problem, because east of the Rio Jururú, there are two candidate harbors: first is Bahia Bariay, which is larger than Rio Jururú, but which is only about half a league distant. Second, we have Puerto de Vita, which is about one and a half leagues from Rio Jururú, and is about the same size. The problem with using Puerto de Vita as Rio San Salvador is that it would mean that Columbus flat-out missed the large and inviting Bahia Bariay as he sailed along this coast. Such an oversight seems impossible. Therefore, we must believe that Bahia Bariay is in fact Rio San Salvador, and that Columbus overstated the distance between there and the Rio de la Luna by about a half a league.

    So we have seen that the navigational records of Columbus are a valuable record of his travels along the coast of Cuba and elsewhere. And although these records are not without error, it is possible, using our insight into the navigational techniques of Columbus, to determine in many cases the sources of these errors and to correct them. Further, we have confirmed in all likelyhood the location of Columbus"s first landfall in Cuba. It may be that some will still dispute this conclusion; but if so, then as my colleague Dr.Tirado is fond of saying, it will just give us all a another pretext to return to this wonderful province of Holguin.

    BIBLIOGRAPHY

    Dunn, Oliver, and James E. Kelley, Jr. (1989).The Diario of Christopher Columbus's First Voyage to America, 1492-1493. Norman and London: University of Oklahoma Press.

    Colón, Fernando (1571) Keen, Benjamin, trans. (1959).The Life of the Admiral Christopher Columbus. New Brunswick: Rutgers University Press.

    Fuson, Robert H. (1987).The Log of Christopher Columbus. Camden, Maine: International Marine Publishing.

    Henige, David (1991). In Search of Columbus: Sources for the First Voyage. University of Arizona Press.

    Henige, David and James E. Kelley, Jr., compilers (1993). The Working Papers of the Columbus Round Robin. Madison: University of Wisconsin Libraries.

    Jane, Cecil, ed. (1988).The Four Voyages of Columbus. New York: Dover.

    Kelley, James E. Jr. In the Wake of Columbus on a Portolan Chart. Terrae Incognitae 15, 77-111. Morison, Samuel Eliot (1942) Admiral of the Ocean Sea. Boston: Little, Brown & Co.

    Morison, Samuel Eliot (1963) Journals and Other Documents on the Life of Christopher Columbus. New York: Limited Editions.

     

     

     

    Autor:

    Keith Pickering