 And I want to thank Jeff and the MacLung Museum generally, the staff, for inviting me down here and being such wonderful hosts for the couple of days I've been here. How many of you have actually seen the map exhibit? Can you raise your hands? Fair number, okay? Well, I urge those of you who haven't seen it yet to go and see it. It's a really fine collection of very important maps to be assembled in this spot, some great maps of North America and the world and some very interesting maps of Tennessee and your area. So, by all means, go and see it and hopefully a few of the things that I'll talk about today will help you to appreciate it more. My topic today, how did they do that, comes from what I think is a very basic question that people ask when they look at maps. We've all had the experience of standing in a field or on a seashore and looking out and thinking, no, how would you go about mapping where I'm standing? How could that happen? And the fact of the matter is, if we're standing on a flat surface like this and when we look out, we can see something like three miles. That is, if you're six feet tall, for me, it's more like two and three-quarter miles. But that's not really a wide enough scope to get you to see much topographic detail. If we climb up to about 500 feet, we increase our visibility to about 27 miles, which is getting far enough to be able to depict coves and things like that. If we go up to the top of a 10,000-foot mountain, like this is Mount San Jacinto outside of Palm Springs, your visibility extends to about 125 miles, which is on a clear day enough to be able to generate a fairly good sketch of the surrounding area if you know how to do that. I can't say that I do. If we're at 30,000 feet in an airplane, we can see something like 212 miles. And there you really begin to be able to pick out considerable topographic detail, and many of you who enjoy window seats on your flights sometimes think that it's like a map going by underneath you. Well, if we go up even higher, this is the Horn of Africa taken from the shuttle Columbia in 1993 at 163 miles up. And we're looking north. There's the Horn of Africa. This little projecting thing, I don't remember the name of it, but it's actually the eastern most point of the African continent. And from 163 miles up, you can see about 1,200 miles. So when we get out to the horizon here, we're looking into the middle of the Arabian Peninsula. And there you begin to see a real recognizable piece of geography. In fact, here's a map from the Newberry collections from a Portuguese atlas of about 1565, showing that very area. You see we have the Horn of Africa. There's that little projecting point. And there's the Arabian Peninsula. I think that's supposed to be, I was going to say it's Mecca, but I guess not, it's Jidda, that's probably Jidda. And if we were to wrap this part of the map on our aerial photograph, we'd see that kind of congruence, which I don't know, I think is pretty amazing. Here you've got the Horn. There's this little projecting thing. Here's the island of Socotro, which belongs to Yemen. It's actually out here, but I don't know, it seems to me it's pretty good. And it makes me ask the question, how did they do that? This is the famous blue marble picture taken from Apollo 17 in 1972. And they were at a height of 28,000 miles. So here, of course, you can see the entire globe. And on this particular shot, one of the more famous ones from that mission, you can actually see the entire continent of Africa, except for a little bit obscured by clouds. This is an Italian map by a man named Forlani from about 1565. And I think you'll recognize what it shows. And in fact, if we layer it over that aerial photograph, you see that it fits fairly well. So well that we might ask, how did they do that? This is a map of how many of you recognize this? I want to turn your head this way. It's New England, looking from the east. We're looking west. Here's Cape Cod. This is actually Lake Winnipesauke in New Hampshire. Here's Rhode Island. I think this is the Connecticut River. It's actually the first map published in America, 1677, in John Hubbard's history of New England. We're going to lay it next to a modern satellite photo. And I think you have to agree. It's pretty remarkable. I mean, if you start looking at details, well, okay, Nantucket isn't, or Martha's Vineyard and Nantucket aren't quite in the right place, and Rhode Island is actually further out there. But generally speaking, it's not bad, and you wonder how they did that. And I want to just have a little local example. This is General Smith's map of the Tennessee government. I think it's 1825. And of course, you can see Knoxville. And here is the modern satellite image. Now, of course, I don't want to make any claims that this is an incredibly accurate map, but it does show, there's Knoxville there, it does definitely show its position between these two northeast-southwest trending rivers. And you certainly do see the northeast-southwest trending mountain lines. So how did they do that? To begin with, I want to go way back to the ancient times and answer a question that many people, I don't know, when I grew up, I learned that at the time of Columbus, everybody thought the world was flat and this kind of thing. The fact is that anybody with any scholarly pretensions or even any practical navigation experience knew very well that the world wasn't flat. But it's a hard thing to realize when you're standing on the world, standing on a beach. And this is a little from a cosmography, 1524, that attempts to explain to people, to give them one proof for the rotundity of the world. And what he's in effect saying here is, here's the moon, here's the earth, and here's the sun. If the earth were a, what, a tetrahedron or something like that, the shadow that the sun cast on the moon would be this shape. If the earth were pyramidal, the shadow would be this shape. If the earth were cube, you'd get a shadow like that. But in fact, the earth is round, and so you get a shadow like that. So it's not, certainly not the case that everybody knew the world was round. But it was, it was well known. And in fact, as long ago as 200 BC, a fellow named Eratosthenes was able to actually measure, come up with a pretty good estimate of the, the actual circumference of the earth. And this is the way he did that. This is Egypt, and he understood, he knew that in Sain, a place which is actually very close to the Aswan Dam, there was a well. And on a certain day of the year, the sun was said to be directly above that well. And you knew that because if you looked down this very deep well in the desert, you could see the reflection of the sun. So he did an experiment by, he lived, Eratosthenes lived in Alexandria, and he did an experiment in which on the same day that that well was supposed to be illuminated in that way. He measured the angle of the shadow cast by a pole, a perpendicular pole in Alexandria. And through some fairly elementary mathematics, he assumed, he assumed that in fact they were more or less on, on a north-south line. And in fact, they are more or less on a south-west, a north-south line. And so he did this experiment, here's a, here's a side view of what he did. Here's the well. Actually, this is graduated in miles, it's about 480 miles. And here in Alexandria, when the sun is, the sun's rays of course are absolutely parallel because the sun is so far away and the earth is so small by comparison. So when the sun's rays penetrated to the bottom of the well in Sain, they cast a shadow this big in Alexandria. And the, the geometry of it is pretty simple. If you measure the angle cast by the shadow, it's the same as this angle here, this sector of the earth. And he calculated that that was 7.5, 7.2 degrees or 50th of a circle. So if you take, he reckoned the distance as 5,000 stadia. If you take 5,000 stadia and multiply it by 50, you get, you get a figure which translated in miles is about 24,860, or 24,000 miles. And the actual figure is 24,860. So he's, he's off by 9%. But I think, you know, pretty reasonable calculation considering the instrumentation he had available. We're going to move now quickly to the first, the first really important and in, in many ways the most influential cartographer who ever lived and that's Claudius Ptolemy. He lived in the second century AD, worked right around 125 AD, of course we don't really know what he looked like but this is a 16th century imaginary portrait. And Ptolemy was a, was a polymath. He wrote treatises on astronomy, on music, on mathematics. He's actually most known as an astronomer probably. But one of the treatises he wrote was called Geografia on geography and by which, by which he meant the mapping of the world, geography, the writing of the world. And he conceived, he knew of course the world, the earth was round and he was a sphere and he conceived that the, and this was the general Greek view, that the, the area in which people lived, the oikyumine was one quarter of a sphere and they assumed, they knew a little bit about, about what was down here. Well actually they didn't because here's the top part of Africa and they really didn't know much about that but they assumed that there had to be four other pieces of, of landscape on this globe to, to balance it out. So he came up with one of the things he invented was this projection. This is called Ptolemy's first projection. It's a cylindrical projection and it shows 180 degrees from his western end which was the fortunate isles. People aren't sure whether, some people think it was the Canaries and Madeira, some people think it was Cape Verde. But whatever it was, it was sort of the farthest out thing in the Atlantic that Ptolemy and other Greek geographers knew of and he drew it 180 degrees, in other words, halfway around the globe. And his, the extent north and south is from a little bit north of 60 degrees, the parallel of Ptolemy to the parallel opposite Mero, Mero is a town in, in North Sudan or was a town in North Sudan at about 15 degrees below the equator, there's the, there's the equator. No, I'm sorry, there's the equinoct line. We're, we're all north of the equator here. So his second projection is a little more, suggests a little more of the globular shape. This is Ptolemy's second projection and this is the world map that he came up with. And it shows, you know, the 180 degrees here are the fortunate aisles out here, whatever they are. And you notice Africa is, it's pretty unknown down here, all he knew about was this part and the assumption was that the, the Indian Ocean was, was a closed sea. Just to orient you a little bit, and of course orient comes from the fact that many older maps were oriented with east at the top, hence Orient. But to put you in the picture a little bit, this is, this sort of misshapen thing is the Indian subcontinent and this is the island of Sri Lanka, Ceylon. This is probably the Mele Peninsula. So he came up with a, a world map and also 26 regional maps. He made a map of, he made 10 maps of Europe, 4 maps of Africa and 12 maps of Asia. Now how did he place things? He talks actually about how, how to make a map and the first thing he says is well, because the earth is round, you really should start with a big ball. But that's kind of difficult. It would be hard for us today too to make, to start with a big blank ball. So, and then he said the next best thing is to start with a slice of a ball. So you have a big curved surface like that and then you can make your map on that. But he says that also is difficult. So let's, let's just work with flat paper. So he comes up with these two projections and he proceeds to plot on them all the places he knew about in the world. One of the, one of the main tools that would have been available at that time was a quadrant looking more or less like this, a device that you could sight through on this side and a little weighted plum hung down and if you sighted say the North Star that would read directly to your latitude. Latitude was relatively easy. And in the ancient world some astronomers had very huge models of these things, very large operational quadrants and they could probably read quite, quite accurately the latitude. Another way that he determined how far north and south the place was by knowing something about the difference between the longest, the length of day and the length of night at the equator it's equal. You know, the day, the day is as long as a night. At certain, yes, at certain times of the year. But then as you go north, here's the day of Mirro, that place in northern Sudan. There's a one hour difference between the longest day and the shortest day. At Sayin, a place in southern Egypt there's a two hour difference. At Alexandria it's about three and a half. By the time you get up here to the far north like Denmark it's about nine hours or more. So this is the kind of information he would have gathered from Roman legions operating in England and Germany and Spain and France how long the longest day was in various places. So that would be how he would, how he would set his latitude. So here he's, this is how he would plot the latitude of, he knew that Alexandria was 31 degrees north. He calculated that it was about 60 degrees and 30 minutes east of the fortunate islands. Now how would he have known that? He talks about one way, of course, longitude is time. One hour of time is 15 minutes of longitude. And what we learned, we know now that the most accurate way to understand longitude is to be able to carry an accurate clock from one place to another. And of course it took hundreds, it took thousands of years for that just to be finalized. It wasn't until John Harrison in the 1780s that they actually had a chronometer accurate enough to carry time that way. But even in Ptolemy's day he was aware of other solutions. He said if you had accurate information about the timing of eclipses, if you knew that an eclipse observed over here in Damascus happened at midnight and it happened and it was observed at like 1.30 in the morning in Alexandria or I don't know in Cadiz or something, then you would be able to use that as an instant of time and calculate the distance. So you, and he had some information like that. There was a little bit of information about eclipses, but there had, a lot of information had been gathered about the distances of places. Of course the Romans were wandering all over their empire and they were very active in Britain a little before Ptolemy's time and so a place like London was nailed down. And it's probable that most of Ptolemy's longitudes are actually cobbled together from distance measurements. So from Alexandria here he would have, of course he had access to the Alexandrian Library which was full of information and access presumably to all sorts of Roman records and itineraries and things like that, virtually all of which is lost to us now. But he knew that for instance if you went from Alexandria to Algiers or Tunis that it took, that it was so far you know they reckoned it was so many Roman miles. He actually had a system whereby if he had an itinerary distance between two places he knew of course that any road is going to be a little windy. He allowed for one fifth error. So he said if he had a distance of, there was 500 stadia or 500 Roman miles say from Alexandria to Tunis he said well okay I'm going to count that as 400. And then he would establish the longitude of Tunis or of London or of some other city. So in a very slow and painstaking way I'd like to envision Ptolemy as working on one huge map maybe on a wall or maybe even more conveniently on a floor like this and having drawn out his projection and saying okay here's Alexandria and I know Damascus is this far away and it's at this latitude then I'm going to say it's here and gradually shifting back and forth and moving things around he came up with his world map which you saw earlier. Just to sort of sideline in a way about the discovery of America Ptolemy's, this is a globe made in 1492 by a German named Martin Beheim who was working in Portugal. Now there's no evidence that Columbus ever saw this globe although if there was one globe there may have been more. I mean I'm sure it wasn't a unique object. So it's not at all unlikely that he saw this globe or something like it. This was a concept that was clearly out there and basically what this globe does is it takes Ptolemy's world and wraps it around a globe. It happens though that because Ptolemy actually didn't accept Eratosthenes' measurement apparently for the size of the globe. I don't remember what the reasons were but he posited a somewhat smaller sphere for the earth and he actually ended up exaggerating the longitudinal length of the oikumine. So when you wrap Ptolemy's a little too large earth around a little too small globe you get a what we would call Pacific Ocean view that looks like this. This is a projection of the Beheim globe looking with Europe over here and here's China and these islands off of China maybe that could be the Philippines or you know some idea of that. Here's Sipangu which is Japan. This is all information that came from Marco Polo. But what you can see is I love this example because it shows you exactly what Columbus thought he was doing. When he sailed from Spain his idea was to sail west until and these are the islands the Canaries and the other islands in the Atlantic was to sail past all those islands until he hit other islands off the coast of China and indeed he thought when he hit Hispaniola and those other places that those were some of these islands and I believe the story is that Columbus actually went to his grave thinking that he had in fact discovered these East Indies. So I want to show you in a little more detail how Ptolemy went about mapping making one of his detailed maps. Ptolemy's first map of Europe is the British Isles and interestingly his arrangement of these regional maps starting with the British Isles and the second map being the Iberian Peninsula that tradition became very firmly entrenched so that when the first modern Atlas came out in 1570, Abraham Ortelius he had a world map and then his first regional map was British Isles and the second regional map was Iberia and in fact most atlases made until the 20th century followed that pattern. It was Great Britain, it was Spain, then it was France and then so on the order kind of falls apart after that but that was how influential Ptolemy was. So this is a satellite view of Great Britain and this is Ptolemy's map of Great Britain and this is the kind of information that Ptolemy recorded lots of place names of towns, a number of locations of rivers we're not to take this interior detail at all seriously but supposedly the river mouth is something that he plotted. There are some names of peoples here, sort of general names this is where the, I can't read these names on here but this is where this tribe lives and this is where these people live and a few physical features like some mountains and even a big forest here in Scotland. So how did he do that? Well he started with a projection of that part of the world and he put down his best guess as to where London was located latitude and longitude. The British, the Roman legions of course were all over Great Britain and they undoubtedly had regular travel between all these places and he had itineraries telling him how far certain things were especially towns, Tamara actually I think is a river in Cornwall Corinium is, look at my crib sheet, Corinium is Cerencestor Maridunum is Carmarthen and Wales this is the promontory of Kent which was apparently fairly well established because it was where the Roman troops, the Roman ships would, that would be the first landfall there in Britain and so there were a number of places that he had, Ratier is Leicester, Diva is Cheshire, Lindum is Lincoln and Eboracum is York and he adds the note in his geography that this is where the sixth legion won a victory so there were a number of places that he was able to establish fairly accurately in relation to one another where they were and from these, from some of these fixed locations some people even think that the Romans had a kind of a triangulation had a kind of a standard triangle that they worked off of here in surveying, in making maps of England and Ptolemy may actually have had a map of England that he got from someone in the army it's not at all unthinkable that there was a sketch map and they said, yeah well this is what this southwest promontory looks like so anyway using the best information he had he came up with this outline on his big map, let's picture it on the floor here and he also put in the river mouths they said well this river is up here so many miles north of this point here and so he plotted all these places on his map now if he had just done that and made these wonderful maps that would have been enough had they survived but the problem with maps then and still today is that they're extremely fragile and extremely subject to wear and tear and any of you who have a car with a gloving apartment you can testify that in fact most maps get used to death if they're used at all so had Ptolemy made a big world map on parchment or on papyrus or something and had he made a set of 26 regional maps maybe they would have survived maybe copies would have been made would have survived the millennia and he undoubtedly did make such maps I mean he at least made one big map we know that but the reason Ptolemy's geography survived is because he digitized it he took all of these he started with these latitudes and longitudes of towns and then he started plotting the reading off of his base map on the floor let's say he started reading off other coordinates so if you'll follow these dots that I've placed around here he would say okay well at this point of this bulge it's 53 degrees 30 minutes of latitude and about 22 degrees 10 minutes of longitude and he'd write that down and he'd do this for the river mouths for the promontories for all these different features around the island and he came up with dozens perhaps as many as a couple hundred points for the British Isles and he recorded those in tabular format like this this happens to be a Latin manuscript of Ptolemy's geography he would have written in Greek and there are some extant Greek manuscripts but basically Ptolemy's geography as we know it as it came down through the ages consisted of no maps but a textbook of how to do the projections and a general description of how to map and a list of 8,000 coordinates like this here's a place latitude and fraction and longitude and fraction and actually the way he indicated degrees I mean minutes and well he didn't really get into seconds but the way he indicated minutes was he would say if it was we would call it 50 degrees 30 minutes he would say 50 degrees and a half and if it was 50 degrees 45 minutes he would say 50 degrees and a half and a quarter and they didn't have the concept of unified fraction so the geography as it came down through the ages consisted of just data of a numeric data digital data if you will and it wasn't there is some evidence that the Arabs had access to Ptolemy's geography but it was pretty much lost to western culture until the late 1200's I'm sorry the late 1300's when a copy was discovered in Constantinople a Greek manuscript and a geographer in Constantinople said here's a direction for how to make a world map and he proceeded to plot out these 8 having drawn we don't know if he did one big map or made regional maps but he followed Ptolemy's instructions he plotted out all these 8,000 places and produced this atlas well that was a revolutionary thing and that atlas very quickly got translated into Latin and many many copies were made of it and it became the first standard atlas of the world this in about 1400 and it in many ways it stayed the standard atlas of the world for at least 100 years Ptolemy's geography was one of the first books to be published the first edition with maps was 1477 a very early illustrated book and it were multiple editions all through the 16th century it wasn't until about 15, in 1570 when Ortelius came out with his Theatrum Orbis Terrarum that's thought of as the first modern atlas but until that time until the 1520's Ptolemy's maps from 125 AD were pretty much it for understanding the geography of the world of course when the new discoveries happened they had to think on their feet and there are several maps there's one map in particular I'm thinking of in the exhibit where you see what's basically a Ptolemy's world with some American stuff tacked on but to get back to his map of Britain many of you may have wondered why Scotland is bent over like that I haven't read actually anywhere anyone saying this explicitly but I'm pretty convinced this is what happened if you turn that bit of Scotland up on end like this, 90 degrees you'll see that it actually is not a bad rendition of Scotland I mean you get the basic peninsula up here this Moray Fir you get this peninsula here these little fjord-like things over on the west side it's not bad for 125 AD drawn by a guy a couple thousand miles away who never left Alexandria working from verbal descriptions probably but the reason he had to bend it was because of the island of Tule you remember that zonal diagram it showed the sort of northernmost habitable place as the latitude of Tule well Tule, this is from a map of 1539 showing this imaginary island some people think it actually might have been Iceland or possibly some other faraway island in the North Atlantic but basically Ptolemy's information went back to Pythias who said that Tule was six days sail north of Britain and is near the frozen sea and the idea was that when you got that far north much beyond 60 degrees north that the entire sea was frozen and it would obviously be uninhabitable so Ptolemy was in a pickle because he had a lot of information from the Roman legions about Britain and about Scotland and he clearly knew that when you got up here there was still about this much more to go but he had the problem that here was his Tule he had plotted Tule as this location and according to Pythias it had to be six days sail north of Britain and if he put it up this way it just didn't fit so he did what a lot of scientists do today they try to understand the data in the way that seems to make the most sense and for him he tries to preserve the length of Britain while at the same time recognizing that Tule is pretty much the northern limit of habitation so he's simply bent it that's my view and I challenge anyone if anyone has another explanation they're welcome to give it so anyway this is Ptolemy's world the same world that's wrapped around that Bayhime Globe although the Bayhime Globe also includes information from Marco Polo which extends China out here and gives us Japan moving now to the Mediterranean we're going to talk about another great Ptolemy's the discovery of Ptolemy's geography in 1400 or thereabouts is just an epical thing in the history of cartography the whole idea of mapping on a grid latitude and longitude that all comes from Ptolemy but there was another tradition that had started a couple hundred years earlier that in the Mediterranean that is sort of a parallel tradition and that's the tradition of the Portal on Chart this is the earliest known copy of the Portal on Chart and some of the characteristics of Portal on Chart well they're almost always drawn on an animal skin on vellum this is the neck of the animal can you see the outline here we're looking at the Mediterranean down here is the Strait of Gibraltar and here's North Africa here's the Italian the boot of Italy here's the eastern shore of the Mediterranean and actually the Black Sea was almost always included in Portal on Charts and the Black Sea has been somewhat eroded here actually this map one of the most important maps in the history of cartography was found in a Paris junk shop in 1840 something and it now lives in the Bibliothèque Nassir now here's a detail of the Cart Pisan as it's called which shows you in greater detail some of the characteristics Portal on Charts invariably have a circular grid if you step back you can actually see you can see a couple of great circles here inscribed that have wind roses in the middle and radiating wind lines or rum lines as they're called R-H-U-M-B the place names on Portal on Charts are always written inland they tried to leave the water spaces as open as possible typically the rum lines were different colors some were green, some were red some charts have black ones another characteristic oh they show tiny little rocks there's another example I can show you some more symbols and the other thing is that there is no up on a Portal on Charts there's just no, you can't say oh this is meant to be up the lettering if you'll see these are meant to be read from that way and then down here I can't quite make that up they're still read that way but over here they're read this way and if you go around an island you have to kind of so you'd have to kind of turn the chart around like that so it didn't really have a natural up this is another Portal on Chart this is from the Newberry's collection this is our earliest Portal and we have a couple dozen Portal on Charts and Atlases this is 1456 done by a Roselli from Mallorca he signs it up here in the neck and again it's the outline of the Mediterranean with the Black Sea some of them also went up most of them went up the west coast of Europe included the British Isles usually very often they would put these maps these flags around the border many of the Portal on Charts that have survived the Cart Pisan is a pretty tattered and torn thing and was not probably terribly attractive when it was made some of the Portal on Charts that have survived are very pristine, lovely things that probably were made for rich clients or for parlor use or library use but there are some that give evidence of having been to sea and I think this is one of them over here on this side are these holes? that's where it was nailed onto a wooden roller and over here on the neck is a little hole there would have been a leather thong through there so you'd roll it up and tie it with that thong and stick it in a cubby hole on board ship and it's definitely seen somewhere here for me rolled and unrolled and even some of these flags have obvious signs of ink the pigment having gotten wet so I don't know I like to think this one may actually have gone to sea anyway, how were they used? this is another Portal on Atlas from the Newberry it's actually an Atlas this is an opening of two pages I've had to join the sheets here the digital copies but to show you how Mariner might use a Portal on Chart like this if you wanted to go from this Malia I think it is on the north coast of Africa to this point over here Cabo da Gata Cap Cap Cape in other words he wanted to sail a course more or less like that he could draw his course on there or lay a parallel ruler between those places there's one side of the parallel ruler and then he'd swing out the other arm of the ruler until he lined it up with a wind rose and in this case as you can see that's the north line north by east north north east it's actually in between north by east and north north east so the Mariner starting out from here would try to get his compass to read a little bit east of north by east and hopefully would strike this point but hopefully not literally because as a matter of fact there's an indication here that there's a big rock there and I think if you're familiar with modern nautical charts I think something very like that is used today to indicate a hazard to navigation like a rock little dots like this to indicate shoals some of these Portal on Charts even have a little ship's skeleton to indicate a wreck a sunken ship so the main tool was a compass such as this one we don't really have any really ancient compasses the compass was they used to say that it was invented in China and carried to the Mediterranean now people think that it may have been independently invented but anyway there's textual evidence that people talking about sailing with compasses sailing by the magnetized needle in the early 1200s and so that's about the time the Cart Pisan comes out sometime in the late 1200s the earliest compasses may have been just a needle actually floating on water held up by surface tension sometimes they would push the needle through a straw and that would keep it afloat but I'm sure by a very early age they had devised this method of a card with the needle attached underneath and they would have needed an hourglass or in some cases a minute glass or a half minute glass and navigators from at least the late middle ages up until well into the 18th century were using a log and line to gather information about their speed basically you needed a spool with a lot of line on it you needed this log here or chip and you needed a glass that was good for half a minute and the way it worked was something like this I think you must have needed at least three men one guy is holding the log reel another guy is holding the 30 second glass and another guy is holding the actual chip here which is weighted at the bottom he throws this thing over the back of the chip and it hits the water and starts bobbing along and of course the water catches it here so it's sort of riding up in the water and he waits until about the length of the chip there's a red rag tied there and that indicates that the thing is now far enough behind the chip so that it's free of the wake of the chip and supposedly it's kind of digging into more troubled waters and when that red line goes over the rail he says turn and the guy with the 30 second glass turns the glass and then they start counting how many knots go over and the knots are placed apparently there were a couple different lengths of knot but the knots are placed at regular intervals along there and you count how many knots go over and when the glass runs out the guy says stop the guy holding the rail holds it they count how many knots have gone over and they record that information on this device which is a Traverse Board and this is a wonderfully simple device that didn't require any great learning an illiterate seaman could use it as long as he was familiar with the points of the compass and could read the numbers I guess from one to twelve the idea is this here are all the points of the compass that you could possibly steer each of these concentric rows of circles is a half hour so this would be the first half hour of a watch the second half hour the third half hour and so on up to the four hour watch a very standard way of breaking up the day at sea from early on and attached to the middle a cord and you have a bunch of little pegs to go along with it which you can push next to the cord into a hole so what this tells us is that in the first half hour of the watch they were sailing north by west on that course and in the second half hour of the watch they were still sailing north by west but when the third half hour came along they had shifted their course to this point of the compass and in the fourth half hour after two hours of sailing they had shifted it to this point so you'd keep doing this and for the four hours of a watch you'd have a perfect record of the course you had steered now how fast were you going? well every hour they would do this business with the log the chip log and they would plot those down here each of these lines is one hour of the watch that's the first hour the second hour the third hour the fourth hour what this tells us is that in the first hour of the watch they were going six knots so they put the little peg there in the second hour of the watch I'm doing all this pointing and I made this elaborate slide to show you this I forgot about it so there's the first hour six knots in the second hour but a little more than eight knots in fact eight and a half knots they could record down to the quarter quarter of a knot so that's a fairly accurate estimate of your speed so at the end of a four hour watch the seaman could hand this board over to the captain or whoever was keeping records and they would have a complete record of distance and direction and speed for that watch which they could write down into a log well how did portal I see Jeff looking at his watch yeah okay that clock is right I'm doing alright how did how did the how did this information get recorded ultimately a lot of a lot of this of seaman's information about distances from ports and things like that got recorded in a itinerary form like this strictly well I will say I will call it again a digital a digital record I mean it certainly it uses numbers here's a Roman there are Roman numerals in here and alphanumeric characters to record certain information and this is the kind of information they record these are called Portolani port books of books of sailing directions between ports and this is a the most famous Portolani is the Compaso da Navigare from the again the late 1200s and here's just one one of the indications that go from Fannaro this port to Filia it's 30 miles to the northwest and then there's sometimes notes about about the place but it's just one thing like that after another going around the whole course of the Mediterranean and the Black Sea that's what's in the Compaso da Navigare now people have long imagined that there had to be some connection between these these Portolani these books of of directions like that and the finished Portolan charts but it wasn't until a couple decades ago that a a retired physician Jonathan Landman actually took the trouble to convert all of the measurements all of the information in the Compaso da Navigare into into distances standard distances and directions he took and when he read Northwest he turned that into so many degrees when he read Northwest he converted that into so many degrees and then he plotted down the distances and those bearings and started to see what would happen and in fact he discovered that the Compaso da Navigare if you plot down all those distances and directions it does in fact I didn't mean to do that what do I do just do this yeah it does in fact generate a map of the Mediterranean now of course it didn't it didn't come out exactly like this and if you know anything about surveying now that there's something called error of closure whenever you survey around an area you're not going to it's not going to end up perfectly like that in fact some of this may be way down here or something but as long as you're working with a closed area and this is virtually closed here at the Strait of Gibraltar you know how to adjust it so you just kind of adjust a little bit on every on every angle to make it to make it fit like this well how close was it well it was pretty close there's the modern outline of the Mediterranean so we're pretty sure this is how the basic Portland chart was generated from these from these tables really or verbal lists of distances and directions and of course it didn't happen all at once like that you know it wasn't that somebody there was this suddenly this a compasso da navigari and somebody took that and plotted it and voila Portland chart I mean it must have been a long procedure involving many many errors many errors and many many partial maps I suppose of different areas but it's pretty clear I think that that is the that is the the source and now I'm going to say a little bit about a more continental approach the Mediterranean we discovered is pretty much mapped through very accurate very small scale measurements of distance and direction around the perimeter much the same thing using many of the same instruments is happening on a larger scale when we come to a continent we've already seen one early map of this part of Africa now we're going to look at the at the some of the Portuguese efforts to map the west coast of Africa now another instrument that would have been involved besides the the quadrant that we saw Ptolemy was holding a quadrant there was an instrument called the cross staff which is works the same way you cite an object and you you align this bar of this thing with the horizon and this top of the bar with whatever you're citing north star or sun and you you read an angle off of this sliding bar there's a model in the exhibit here there are lots of wonderful instruments in this exhibit some of which I've never seen before very neat addition to the exhibit and in there is a back staff which is the same principle as this cross staff but instead of having to look directly at the sun you turn your back to the sun and this has a little mirror on it or a little vein and you can read the shadow the shadow of the sun instead of directly but it accomplishes the same thing so using logs and lines and instruments like the quadrant or the cross staff to measure latitude the Portuguese gradually began to map Africa now this is a portion of a 1489 map and I've trimmed everything else away except what Ptolemy knew this is pretty much the Africa that Ptolemy knew it consisted of the north the north shore of the Mediterranean he knew about he knew about the Atlas mountains he knew about the Nile and they knew or thought they knew that the Nile had its source in the mountains of the moon somewhere way down south in Africa they also knew or thought they knew about some big lakes here which I have no doubt were Lake Victoria and Lake Niazaland you know or whatever just you know the word was there were big lakes down there towards the end of the Nile so that was Ptolemy's Africa well by the time the Portuguese really started to make a dedicated effort to get to try to see if they could get around Africa if it was in fact not if it in fact did not enclose the Indian Ocean they started to sail down the west coast and this is this was a very long process I mean 1432 another few years later they get a little further to the river of gold now were 10 years later here were a long time later it took the Portuguese something like 50 years to get to get the bulge of Africa really nailed down but and so they would have done this in exactly the same way by getting by getting latitude readings on these various river mouths and things like that and then by keeping track of their distances and directions and finally the big push to see if they couldn't get around the continent and in 1485 no 1487 8 Bartolomeo Diaz actually rounds the Cape of Good Hope and gets as far as the Great Fish River where he can see the coastline trending north so this is the Africa that that is known after Diaz's expedition 1488 and in fact this map is a world map made by a German called Henrikus Martellus in 1489 this is a manuscript at the British Library there's another copy of the Martellus map with very much the same geography at Yale and of course you can see the this is still Ptolemy's truncated South Asia and is very huge Ceylon Toprobana and the but here it does have some indication that there is from Marco Polo that there are these islands off the coast of China so that is that is how continents are mapped in a very basic way and that is how North America ultimately was mapped to now I want to conclude with a case study of how how the interior of continents might have been mapped and or was in this case how it was mapped these are the Great Lakes of course and I think you can see that it would be it would be a much different proposition to try to map the Great Lakes by coming in here and making a circuit of the lake and then measuring this distance down here and then making a circuit of this lake and circuit of this lake and stringing those all together into a you know and the way we did with the Mediterranean that would have been a tall order and in fact it didn't happen on these lakes for hundreds of years were voyagers in in Birchbark canoes so you ended up with fairly crude maps of the Great Lakes this is actually the first map to show all five of the Great Lakes and you can see Lake Superior they obviously were up here in near this straits of Mackinac and they knew there was a big lake opening up there but they didn't know how big or where it ended presumably Lake Michigan although Lake Puan the name of Green Bay is usually Bay de Puan so that would be Lake Michigan Huron Ontario and Erie but I'm showing you a series of maps that attempt to represent the Great Lakes to show you that there's no such thing as as nice linear progressions in cartography we like to think there was an improvement on the last map and I suppose in some cases that is the case but if you look at a lot of early maps you'll see a lot of stumbling a lot of just plain you know I don't know making things up cartographers have always borrowed wildly from other cartographers I mean until very recently when we can actually go to something like NASA and get or some digital image laboratory and get up-to-date photographs of the Earth's surface until very recently when a cartographer was asked to make a map of such and such area the first thing he did was find another map of that area and use it as a base map and maybe adapt it or change the scale or something like that most maps are actually made from other maps and at this time too people were copying each other so as we go through these stages of the Great Lakes you'll see some some things that look the same as say oh that looks like he copied that from so and so one of the things that I'm always interested in is when it comes to the Great Lakes if you can define the shape of Michigan both its southern peninsula and its northern peninsula you have almost completed a map of the Great Lakes and if you you'll watch Michigan through this series of slides I think you'll see a hard little peninsula to map surprisingly one this is a nice example of how progression is not linear in cartography this happens to be very early in fact the first map of Lake Superior 1671 we know it was done by the Jesuits it's published in the Jesuit relation we don't really know who did it Father Alues was one I think Father Marquette may actually have been involved he was up here at the mission on the Apostle Island but it's actually a very accurate map of Lake Superior it has Isle Royale here it has just a couple of little minor islands that are actually there and the reason they were able to do this is we know that the Jesuits actually made a pretty much complete circuit of the lake in canoes counting counting paddle strokes perhaps I don't know but estimating the distance and taking readings of latitude with an astrolabe or with a quadrant here again Michigan is a little distorted look at Lake Michigan on many of these early maps actually there are some where it's swinging way less way some where it's almost straight up and down and some where it's way over at this angle Michigan is like a pendulum Frankelon very influential maker he seems to have have relied I think a little bit on the Jesuit map he knew about it anyway Coronelli Italian cartographer 1680s this is looks like it's copied from the Jesuit map except for some reason he thought he had to make it much wider some fairly some fairly outlandish figures here where this comes from this is the beginning of adding islands to Lake Superior in the late 17th century there were a couple of French manuscript maps made that just suddenly put in imaginary islands and named them after influential characters in France and those islands got picked up on later maps it's always the bad stuff that gets copied first so these these depictions I don't know where they come from Hennepin was generally not considered very reliable traveler or cartographer Dileil was one of the best map makers and actually it's not a bad representation of the Great Lakes he's clearly using the Jesuit map here for Lake Superior and Lake Michigan is actually fairly reasonably oriented Herman Mall one of the more imaginative cartographer Captain Cyprian Southac the first map of North America published in America published in Boston in 1717 but where he got his Great Lakes from I do not know very strange I don't think there was a model for that Papal had a part of Henry Papal's map the Southern Sheets showing the Gulf of Mexico is in the exhibit one of the one of the best maps of North America in the 18th century I have fairly reasonable Michigan and Lake Michigan but notice Lake Superior here he's got Isle, this is Isle Royale and then here's Isle Filippo Pontchartrain and I can't quite read it but there were three or four or five islands just thrown in there to flatter the French officials in fact each one is named after another official so it's nice to have an island named after you here again Lake Michigan way off to the Southwest and Michigan Peninsula just a little point this is the Mitchell map the second maybe the most important 18th century map of North America it's been called the most important map in American history largely because this is the map that in 1783 was laying in front of the commissioners in Paris who drew the they drew a red line on this map showing the border dividing the United States from British colony Mitchell's map is interesting in that this is actually the Newberry's copy badly reproduced but our copy is colored so that you can see that the colonies were at least the Southern colonies were shown with their Western borders extending to the Pacific according to the colonial charters there's a wonderful copy of the Mitchell map upstairs in the exhibit too it isn't colored quite this dramatically but if you see the Charter of North Carolina colony was supposed to extend to the Pacific now if you're wondering where where Western Tennessee would have been had that actually happened this is how it would start out Monterey would be in West Tennessee and San Luis Obispo a nice wine country in there could have been great so a couple more maps attempting to show the Great Lakes I'm going to concentrate on a couple of maps by this English cartographer named John Kerry who publishes a series of maps of regions of of the United States like this beginning in 185 and I guess if you look at the great well they're recognizable and he's gotten rid of the fake I know he hasn't gotten rid of the fake island they're still there there's Royale but there's Philly Po in fact this actually went back to the Mitchell map the Mitchell map was used as I said to draw the treaty of peace can I get back there how far away was it it's when they drew the line for the border they drew it up here and they said okay they drew it across this island and to Isle Royale and they went south of Isle Royale and then they went up a river here and in the treaty it said it said north of the Isles Philly Po and Panchartrain and Isle Royale or something and so they they cited in the actual treaty document two islands that just didn't exist and so for the next 70 years they were they were looking and the British were arguing that oh this is what Isle Panchartrain was and the Americans said no, no, no it was this island and finally it took it took a long it wasn't until the 1840 so when they finally ruled that in fact those islands didn't exist but here they are 1805 it still shows the border going across this non-existent island so anyway this is Kerry's 1805 map and that would have served fine except when in 1805 Ohio became a state and so in later editions he had to he had to add Ohio here the general geography is pretty good there's Chicago the Portage St. Joseph Michigan Detroit but when he got to 1825 by that time there were already Ohio had become a state Indiana had become a state Atlanta had become a state Illinois had become a state and he had to fit them in somehow he didn't change the basic geography he didn't have any better information but you can see it gave him some problems because here for instance it's the bottom of Lake Michigan Illinois first of all is landlocked it has no lake this is Illinois Fort Dearborn in Chicago is in Wisconsin what's not Wisconsin Indiana is here it just it was very hard to fit in and the reason was he actually had a very good observation for the oh yeah this is indicating his basic difficulty how do you fit three states like that into that space between the Mississippi and the western border of Pennsylvania now he knew for a certainty about he actually his longitude for the west end of Lake Superior is pretty good it's actually right about 92 degrees west which is what he shows his longitude for the east end of Lake Ontario is also right on also the western border of Pennsylvania and the reason that's right on is because of the Mason-Dixon line which of course was surveyed on the ground with guys lugging chains and blazing through trees and making paths and marking on the ground how many hundred miles to the western border of Pennsylvania so he had those three those things pretty well fixed but he was very vague about the Mississippi river there weren't any accurate observations out there and this this lake system in here was just very very little known that's the western border of Ohio this is the western border of Indiana and this is the western most bulge of Illinois on the Mississippi so how did this little problem get solved? well unlike our other examples it wasn't solved from the water it was solved on land and it was solved by people dragging chains like this across the country and orienting them with compasses like this the general in the northwest territory which was this area here was decided to divide it completely into parcels of course you folks down here you have the the meats and bounds system where you just sort of set from this tree to that rock to the river and then back this far but they decided they wanted something a little more orderly for the northwest territories and so they devised this system of public lands consisting of six mile square townships and divided into 36 square sections and they first did this in the very eastern part of Ohio in what was called the seven ranges that was done in 1787 they were just kind of experimenting really they didn't quite know how they were going to expand this this grid across the northwest territories but they in Ohio is really very much an experiment if you look at the the land surveys of Ohio there are different slightly different orientations and slightly they don't match up perfectly they didn't really have a standard meridian but by the time they got into Indiana they started establishing a standard meridian so you'd have one north-south line where you you would number all the ranges and all the townships and Indiana and Illinois were both settled from the south so they became states 1816, 1818 but at the time they attained statehood all the whole northern part of the states were un had well they weren't unpopulated but they were lightly populated and did not have the benefit of the township and range survey in Illinois by 1830 about they had actually surveyed a little extension up here because they wanted to build a canal from Chicago down to the Illinois River the Illinois Michigan canal and so they they divided that and the federal government started getting rid of that land meanwhile on either side of it was still Indian country so as these surveys progressed they bumped up into the to the water and it was only really when this survey got up here in about 1830 that they were able to say with considerable certainty and accuracy this is where the western shore of Lake Michigan gets at that point and as the survey continues Wisconsin becomes a state in 48 gradually the entire lower peninsula of Michigan and of course the entire Lake Michigan and the location of the Mississippi River they're all determined accurately by measurements on the ground briefly this is what happened starting with this in Dixon line which after all starts in tide water and was measured by chain and compass and then extending the general land office surveys west and north and east and west they finally were able to determine the outline of the Great Lakes and that's how this little bit of geography got mapped strictly from the land that's all I have to say but I'm happy to answer questions if you have any I'll try to answer them that is yes