NPR/NGS Radio Expeditions
8 Dec 1998
CaliforniaLos Angeles County
- Culver City; NPR West
- 34.01514 -118.38914
Stereo=1; Dual-Channel Mono
NPR/NGS Geographic Century
Norman Thrower & Don Smith
Dr. Thrower, this will be a fairly brief interview...what we¿re looking for is really your perspective on maps...maybe we could start of by saying who you are and what your connection is with maps.
Norman Thrower [NT] :28
I¿m a professor at UCLA. I teach cartography, remote sensing of the environment and geographical discoveries...Norman Thrower.
In your book...you quote Edmund Halley as having said something about maps, how useful they are for understanding certain phenomenon. Could you just....so as to Edmund Halley, what was he talking about, what did he say?
He was saying that the map provides a basis for understanding that words cannot always perform. In fact that is underlined by the fact that pre-literate people...make and use maps. So it¿s a universal language.
why do we make maps?
Because we¿re interested in spatial things, how things are arranged on the earth. It¿s one thing to look at things chronologically, but another to think of them spatially, how their arranged in relation to one another, and that¿s what the map tells us.
Do you have any idea why people first made maps?...
A part of it was way-finding, how to get from here to there and that was fascilitated by the map. Once a person had been over the hill and he had mapped it, his record of that would help other people to perform the same simple function.
And people were making maps before they were even writing weren¿t they?
That¿s correct. So called pre-literate people, we used to call them primitive maps but we don¿t call them that anymore. We call them the maps of pre-literate people.
And maps and human history are intertwined aren¿t they? You said at one point that maps have influenced history and vice versa, what did you mean by that?
Well I meant that the map is sensitive to changing technologies as man becomes more and more complex in his technology. So mapping reflects that. A good example of this is printing. When printing came about it revolutionized cartography. Actually printing of maps began in China 300 years before it happened in the west. But nevertheless, wherever it happened it had a great influence on mapping because of the exactly repeatable graphic statement. You didn¿t have to copy by hand and perhaps perpetuate and even increase errors, but you could make maps eessentially all the same.
Pre-printing press maps, many of them are beautiful...why do you think that people put such an effort in those days to making maps so beautiful?
It was sales promotion. A great collecting area for maps is the European renaissance. Maps from that period are particulary admired because they were used in libraries, usually by wealthy people. In fact, cartography has been called the science of princes. And it¿s a science of princes because next to their families and even sometimes ahead of their families they were interested in their realms. They couldn¿t visit all parts of their territories but they could see them on maps.
And the King of France, when his country was accurately measured, he decided it was too small.
Right, he had lost territory on his Atlantic and Mediterranean borders...
Let¿s talk about some of the major landmarks in the history of maps. Eratosthenes estimated the circumference of the earth. Tell me what he did.
He noticed that when he went to Cyrene...in Egypt, that in the summer solstice the sun was shining directly down a well. But at the same time in Alexandria, where he was heading to the library, he noticed that it wasn¿t directly overhead, in fact it was 1/50, it was an angle of 1/50 of the circumference of a circle. And so using that measure he was able to estimate the circumference of the earth, the difference between Cyrene and Alexandria was 1/50 of the earth¿s circumference.
And he was amazingly accurate....and what about Ptolemy (?)
Ptolemy is important in cartography because he devised map projections for the earth. Actually map projections had been devised for celestial purposes before his time, but he made map projections for the earth and he compiled...lists of places with their position, we could call this latitude and longitude, and so from these later people were able to compile maps. We¿re not absolutely sure if these maps were compiled by Ptolemy but he gave all the tools 500 years later to construct maps according to his methods.
And things pretty much rested there until the 16th century...why is it that so many maps from the 15-16th century have these criss-crossing lines?
Well, these are called Rhumb lines, which are lines of constant compass direction and what they were trying to do was to devise a method that would allow them to get from one point to another with a magnetic compass. That worked fairly well in the Mediterranean and nearly all these porter line or haven-finding charts for the Mediterranean. When they got into the Atlantic, they discovered that it didn¿t work too well and so a new method had to be developed and so the great cartographer Mercator was the one who came up with the answer. He devised a projection where all straight lines are lines of compass direction. Now the problem with this projection is that it¿s been wrongly used. It¿s been used for showing earth distributions and it greatly distorts, especially towards the poles...it distorts badly. But for the purpose for which it was designed, namely navigation along with for some other developments...it was eminently suitable. Which brings up a very important point, that we should use projections with caution and use them for the purposes that they were designed and not for other uses unless they¿re appropriate.
The Mercator projection showed Greenland bigger than North America I believe. Well these were all break-throughs in a sense in cartography. Let¿s talk about the 20th century, there¿s another revolution going on right now isn¿t there?
There are actually several revolutions in this century. Probably the first would be aerial photography and the development of a science called photogrammetry. This permitted maps to be made without ever having to go out in the field. You could make them in an office using stereoscopic principles. You might do a little field checking, but in general the map could be made in an office and could be made more accurately and more speedily and it was at much lower cost than field surveys.
And then there was satellite technology?
Yeah that is a supplement to mapping. Topographic mapping is still done by aerial, overlapping aerial photographs. The satellites allow updating. They¿re very very useful for that. They¿re not so useful for topographic mapping initially because they don¿t allow much stereoscopic opportunity. But the overlapping aerial photographs do. So in this regard, as far as topographic mapping, they¿re supplementary. But they¿re very useful in their own right, the satellite imaging. For instance they permit us to see, through LANDSAT,...allows us to see how crops are developing, whether it¿ll be a good harvest in the Ukraine or not which could affect people in a very important way, namely whether they¿re going to eat or not.
And so, that¿s one advantage to this new technology, another advantage would be greater accuracy I guess.
Yes and also another thing is that these new technologies allow maps to be animated. This is very important. Some stages in the history of the development of mapping are: 2-dimensional mapping from antiquity and then the development of isolines, particularly the contour, which allow the same accuracy for the 3rd dimension which has been possible since antiquity, and then what we could think of as a 4th dimension, that is animated mapping. And we see these nightly on television when we see news announcers say let¿s put the maps in motion. So then they then show a front, a cold front for example, developing and decaying, being replaced by a high-pressure area or a low-pressure area and so on. So we can see a time frame and how things are developing. And this is a very important development in cartography in which I have played some part myself.
In what way?
Actually, animated cartography existed before I wrote the first articles on it. And I wrote a couple of articles that were rather well-placed and influential. And it didn¿t take off immediately. And now there¿s a great interest in animated cartography, and the computer has greatly facilitated its use. In the old methods of animation, using individual cells, that was very time-consuming and difficult, but with a computer that has been greatly speeded up and improved. So the computer is another cartographic revolution. They say that more people see maps on screen now than hard copies on paper.
Will we ever not need road maps that we fold up and put in the car?
No, we will always need the road map. But now increasingly, maps are on consuls and there are programs like Delorme, for example, that allow you to find your way with the help of projected images on a computer or consul. And so, in addition to that we have Global Positioning Systems which allow us to pinpoint where we are. So we not only have a spatial map before us on a screen but also you can pinpoint very accurately with GPS...Recently my granddaughter navigated me from S. to N. California with her laptop computer and a program that she has.
How did she do that?
She did it because she just plugged in this program that she has and as we made our progress along the way she would note the places and suggest places where we might stop and then we eventually arrived at our destination. And her program was a fairly general one, but there are programs that would allow you to arrive at a particular street address and would even have the telephone number of that place.
Norman Thrower, how old are you?
(laughs) Is that a fair question. I¿ve been in cartography for a very long time. I started out in the survey of India in WWII.
Well the reason I ask, was this experience with you daughter amazing to you?
I mean, I was prepared for it...but I thought it was interesting that she should do that and not use a hard-copy map as I might have done for that journey. I mean I¿m quite aware of what¿s going on in cartography, computer-wise, but there¿s a generation now that¿s risen that doesn¿t need the hard copy map as perhaps in our generation we did.
What do you see for the future, is it going to be even more amazing?
There¿s no limit to it. For example the earth is only one body that cartography is concerned with. Cartography isn¿t earthbound. It¿s general principles apply to extraterrestrial bodies. And in fact quite early on, as soon as telescope was developed in the 17th century maps were made of the moon by people like Galileo and his successors and then this has been continued in the modern age with satellite imaging of distant bodies and we now can map with some accuracy planets like Mars and so on. Yes there¿s no end. As long as there¿s a space frontier there¿ll be mapping problems to be solved.
And we¿re actually mapping places before we go there.
Oh yes, that was very important in the lunar mapping, in preparation for the lunar landing in the recent past. The 20th of July, 1969, the lunar landing was preceded by a very active program of lunar mapping so that they would arrive at a very good place. I mean they could have gotten on the edge of a crater but that didn¿t happen because they had mapped the moon with such accuracy. Interestingly, before the United States mapped the other side of the moon, the Russians had actually mapped the side of the moon that you don¿t see from earth.
Let me ask you one other thing. In all this high-technology mapping, do we lose something in the element of beauty?
No, in fact, we increase I think. The maps of certain people like Richard Harrison, who operated in NYC and worked for Time and Fortune, his maps are aesthetically just as good and probably better than those in the Renaissance. And they¿re better because there are better methods of reproduction now. And Harrison did one thing that I would like to mention. He did maps of the underwater areas. The oceans were a vacant kind of blue coloration until the second half of the century when sonic sounding was developed. And traces of sonic sounding gave us a body of data that allowed us to map the deep ocean floors so that we see now that they are just as interesting, these areas, the greater part of the surface of the planet in fact, are just as interesting topographically as the dry land surfaces. They have great canyons, they have seamounts, they have central oceanic regions from which the tectonic plates are spreading. And all this is new in the 20th century, second half of the 20th century really, previously we could only map with a plumb line coastal areas and river basins and so on. Now the deep oceans have revealed the secrets of their topography.
Speaking of the aesthetics of mapping, in your book you have so many beautiful maps, do you have a map collection yourself?
I recently went with a group called the international map collectors to Japan, actually they had given me their highest honor so there was a money award and I went with them to Japan to look at interesting maps there. And I bought maps there and I have a working collection, mainly for the benefit of my students. One of the maps that I bought in Japan showed how the fire spread after an earthquake and how it was controlled. So this is what we¿d call a thematic map. So it seems that any human activity that has a spatial component can and has been mapped. And by thematic mapping. I did an Atlas for McGraw Hill on thematic maps that sold very well actually.
One of the first thematic maps was tracing the outbreak of cholera in London I believe.
Yeah that was a very interesting map by Dr. John Snow and he pinpointed the offending pump. In those days in London, the early 19th century, people were going to get their water from public pumps and by mapping the individual outbreaks of cholera that came to his notice, he pinpointed the one pump that was the offending one. And later it was discovered that the water was in contact with raw sewage there. The other pumps were all right. And it was just one pump. And he discovered this by mapping. But he went further than that and wrote a book called ¿On the means of communicating cholera¿ and he showed the waterborne origins of cholera, and thus mapping was used importantly in this regard. He is greatly admired by medical doctors...for his development of isolines is greatly admired by physical scientists.
You strike me as a person who just really loves maps.
(laughs). I do because I think they¿re so informative and they bring together art and science but they also have a technological base, and that¿s the thing that appeals to me about mapping. There are few human activities that so well bring together art, science and technology. Architecture does certainly, and a few other activities but most are overbalanced on the aesthetic side or overbalanced on the scientific side, but cartography, like architecture has both components in rather equal measure I would say. A map is unsuccessful if it doesn¿t communicate and that could be a function of art and it¿s also unsuccessful if it doesn¿t have a scientific basis too.
She would like for you to say what I was saying about maps and history being intertwined...could you just tell me what you said in the book?
The map very well reflects changing human thought. Because of this balance between art and science, girded by technology. And so it is a rather pure reflection of changing ideas. That is why it¿s affected by every great technological break-through like printing or air travel or space travel or the computer or even printing methods and so on. So it¿s an excellent reflection of the changing thought of the human race.
We talked a lot longer than I thought we were going to because you were so interesting.
...NT asks some questions about air date and cassette copy. Don asks what classes he teaches...
Well I teach...Remote Sensing of the Environment that deals with aerial photography and space imagery. I teach cartography mainly from a historical perspective but also modern cartography as well. And I also teach geographical exploration. And of course geographical exploration has given us the data and material that is mappable, let¿s say.
At UCLA correct?
yes, that¿s correct.
...NT talks with Jessica and the interview is basically over....