Woodruff T. Sullivan III
Interview with Grote Reber In Tasmania March 12, 1978 Interview Time: 1 hour, 16 minutes Transcribed for Sullivan by Bonnie Jacobs
Note: The interview listed below was either transcribed as part of Sullivan's research for his book, Cosmic Noise: A History or Early Radio Astronomy (Cambridge University Press, 2009) or was transcribed in the NRAO Archives by Sierra Smith in 2012-2013. The transcription may have been read and edited for clarity by Sullivan, and may have also been read and edited by the interviewee. Any notes added in the reading/editing process by Sullivan, the interviewee, or others who read the transcript have been included in brackets. If the interview was transcribed for Sullivan, the original typescript of the interview is available in the NRAO Archives. Sullivan's notes about each interview are available on the individual interviewee's Web page. During processing, full names of institutions and people were added in brackets and if especially long the interview was split into parts reflecting the sides of the original audio cassette tapes. We are grateful for the 2011 Herbert C. Pollock Award from Dudley Observatory which funded digitization of the original cassette tapes, and for a 2012 grant from American Institute of Physics, Center for the History of Physics, which funded the work of posting these interviews to the Web.
Part 1 >
Continuing with Grote Reber on 12 March Ď78. Once you got to NBS, one of the things you were interested in doing was building a big dish and you put quite a bit of effort into designing it.
Can you tell me about that?
It was pretty obvious that with the receiving equipment available at that time that everything was sensitivity limited, so we needed a lot of pick-up area to get something to listen to. And a big dish seemed to be the answer. So I made an assortment of engineering designs and built a small model and tried to promote it, but I didn't get anywhere because it was only 1948 or 1949, and that was about 10 years before big dishes got any kind of respectability. This design, of course, was an enlargement and pretty much a copy of my 30 foot dish in Wheaton. Then the blokes at Sugar Grove copied my design and expanded it up another factor of three to 600 foot and then failed.
Some things you just can't scale up.
That's right, you've got to do more than just scale up.
Did you have any cost estimates for it at that time? We saw an entire bow of drawings, etc.
Oh, no, we didn't cost it, but it was going to cost a couple hundred thousand dollars, anyhow, even in that day. I canít remember how many tons of steel went into it. It was designed as cheaply as possible. It used simple, well-known and available steel members.
And this actually was considered by AUI [Associated Universities Inc.] in the mid Ď50s also as a possibility.
Well, yes. AUI finally got started in the middle '50s when NSF [National Science Foundation] got underway, and they were looking around for a design for a big dish. And I offered my design and it appeared in one of their resumes of the state of the art. But it wasn't chosen, they elected to do something else.
Now we are driving to the airport with a bit of background noise. I'd like to ask you about some of the other interests you've had besides radio astronomy, electrical engineering, and ionospheric physics, which weíve discussed on tape before. The first one I think historically is the beans business. Is that correct?
And can you tell me how you got interested in that and what you did?
I was in Hawaii at the time and my neighbor planted a row of about 20 poles with climbing beans on them. And I noticed that they all turned the same direction. And I called it to his attention and much to my surprise he had not noted that even though heíd been growing these beans for 20 years, perhaps. So I said, "Ah, look, Jerome, how about me taking all the odd numbered poles and reversing the vines forcibly, tying them back?" He said, "Sure, we've got plenty of them here; if some of them die it won't make much difference." So I did that and these vines grow fairly rapidly during their few weeks of the growing season so I had to wind them back and tie them about every three days. And these plants grew at the same speed, apparently the same amount of foliage, and they flowered profusely and produced a considerable number of beans. And so we picked the beans and ate them and they were just as tasty as the ones that grew on normal vines. You couldn't see any difference whatsoever. In other words, handling the beans in this fashion didn't seem to have any effect as far as the growth of the plant, the prolifieness of the fruit, or the taste of the fruit- no effect. Well, that wasn't a very good experiment because it had no control. And the main thing that was out of control was the amount of water in the beans, they were all green. So I determined to do the whole thing again but much better. And about that time I went to Green Bank, West Virginia and worked there for a summer.
What year was that?
About 1959, I think. I decided to try several varieties. So I had a patch plowed up and got a bunch of stakes and put in several rows of different varieties, each row had about 30 stakes in it. And the odd numbered ones were allowed to remain normal and the even numbered ones were reversed. So we had a similar number of normal and reversed vines. This time, instead of picking the beans and eating them, decided we'd try to do it more quantitatively, so I let the beans in the pods mature on the vine and they dried and withered and got crinkly and most of the water went out of them. So this reduced one of the variables. Well, the bean pods come in different sizes, some of the smallest ones had just one bean in, and there were two bean pods, 3, 4, 5, 6, 7 and sometimes even 8 or 9 beans in a long pod, although they were quite rare. The average pod maybe had about 5 beans in it. So then they were divided up into groups, that is, how much did 100 bean pods weigh that had one bean in from an the normal vine versus the reversed vines, you get the same answer. Two beans in, about the same. By the time I got 3 beans, l it was apparent that the pods from the reversed vines weighed less than 100 pods from the normal vines. And this situation accentuated as the number of beans in a pod increased.
It looks like it was significantly difference?
Oh, definitely. Something like about 12%. So, it was apparent there was something about this thing which was influenced by an end effect. If the pod had a lot of ends compared with the center, then you couldn't see the phenomenon. But if the pod was a long pod and had small ends compared with the center, then the effect was more pronounced.
You're saying an 'end' effect?
Yes, that is, whatever was changing, was changing along the center of the pod, not the ends.
Oh, I see, yes.
In other words if the pod had a high ratio of end material to center material, then the phenomenon didn't appear, but if you had a high ratio of center material to end material, like a long pod, then the phenomenon was present and it increased. So then the pods were shucked, that is, the husks were taken off and the beans taken out. And they, of course, were all carefully sorted. So we had a group of beans from pods with one bean in, another group with two beans, another group with three beans, and so on. And then 100 beans in the three bean group were prepared to be weighed with a 100 beans of the normal vines. Of course, I guessed wrong. I couldn't see any significant difference, the same with all the other categories. So the difference was not in the beans. So then I weighed the shucks, and thatís where the difference was, in the shucks. It turned out that the reversal vines' pods had lighter weight shucks, at least in the upper categories. I couldnít find anything in the low-bean shucks. So there was something about the shucks. And I tried to measure things on the shucks with a micrometer, but theyíre so crinkly...
A little squishy, eh?
That's right. I couldn't make anything out of it. And this was done again a couple more times in some other varieties and they all responded in the same way. So, this demonstrated that if you handle a plant in this particular fashion, it reacted in that particular fashion, but nobody explained why it did this, although the handling of plants is nothing new, that is, orchardists manipulate their trees and they prune tomato plants to make them fruit sooner, and hedges are manipulated. It's a common thing, but as far as I know nobody else had ever tried it with beans.
Did you search the literature at all to see if anyone had worried about the sense of the helicity?
Oh, yes. That's a very popular thing, especially in the 19th Century. There are lots of articles about that. And the best one though was in a book written by a man whose name I can't remember, but he was an Englishman in India, in the heyday of the British Imperial India, and he taught school in Bombay [Reber: Calcutta]. But he had a lot of time and a lot of assistance and he used to go out and search the Indian countryside for interesting kinds of plants. And he wrote several volumes. One of these was "Turning Vines in India." [Reber: Published by Royal Botanical Society of Calcutta]
I see, a whole book!
A whole book. And he had a lot of them, that is, whole scores, I didnít count them up, but he divided them up into right-handed turning and left-handed turning vines. This book had about 400 pages and they were approximately equally divided, about half as many pages on one direction and half the pages were the other. So in India the number of vines turning one way are equal to the number of vines turning the other way.
But the same species always turns the same way?
Well, not necessarily. A dozen beans, all of different variety turn the same way. And all the different varieties of hops turn the same way, which is the opposite way to beans.
No, but I mean if you have a single species all individual plants always turn the same way.
There are some that go both ways?
What part of the book were they in?
I don't remember, I didn't read the book, to be honest. But my own observations are that there are some species of climbing plants where some of the members turn one way and some of the members turn the other way. For instance, there's a bulb in California called rhodiea blumibus that grows on the slopes of the Cascades. Anyhow, the slopes of the mountains there, and rather high up, itís small. It sends up a single runner, it looks like a runner of climbing beans, but there are no beans on it. It just has this long flower at the very top. It grows maybe 6 or 8 feet high. I found this in the Santa Ana Botanical Gardens near Pasadena. I wandered around there one day while I was staying with a friend in Pasadena. And here was the peculiar kind of vine growing up a small wire trellis. And they were obviously coming out of bulbs in the ground. Some of them were turning one way and some were turning the other way. And they were all rhodiea blumibus.
So I went in to the office and introduced myself and asked to talk to the head botanist, a man named Mr. Everett. I discussed this with him and he knew that this plant was there but he was not aware that they turned one way or the other way, or that they were turning vines. So we discussed this and I had him get out the card file to find out where they came from and how long they'd been there and how fast they grew, and all that kind of stuff, which he obligingly did. And while we were digging through this, a rather large heavy-set, gray-haired man came in, and injected himself into the conversation and came out with an absolutely flat statement that climbing vines turn one way in the Northern Hemisphere and turn the other way in the Southern Hemisphere. And I said, "Well, sir, I don't think that is true because I've been in Australia, having just come back recently, and I have planted beans down there and they turn the same way down there as they turn here." He says, "You didn't do it right." So I said, "Well, maybe I didn't do it right, but this is what I saw." "Well," he says, "there was something the matter."
I think he may have gotten mixed up with his freshmen physics course about tubs draining.
So, he then lit into Mr. Everett about this subject matter and Everett wanted to argue with him about it. Then he turned to me and he says, "It has been proven in the literature that vines turn one way in the Northern Hemisphere and turn the other way in the Southern Hemisphere. It has been proven in the literature!" So I figured there was no point in arguing with anybody who had seen it proven in the literature. Anyhow, about this time the thing got so heated that I decided it was a good time to leave. So there was another gentleman there named Mr. Ball, who was head gardener. So Ball and I left. Ball was obviously just as anxious to get out of there as I was. So Everett was stuck with this gentleman. So after we get out, I said to Ball, "Say, who is that big old gray haired fellow with the crotchety disposition?" And Ball says, "Oh, that is Dr. Muntz, he's the Director!" So, Obviously Dr. Muntz knew what was in the literature but he didn't know what was going on in the garden. Anyhow...
Did you ever look up these papers?
Well, then I got home late that night where I was staying with my friend. He taught school in one of these places around there, and I mentioned this to him. He said, "Oh, think nothing of it. That is the way Dr. Muntz is. You have accidentally, somehow, stepped on one of his pet peeves."
Did you ever look up these articles?
This fellows name was Bill [?]. He says, "Weíve got a little time this evening and it seems to me that Muntz has written a new book recently." So we went over to the university or some college library, and it was open, and so Bill fished up this book by Dr. something or other Muntz, and thumbed through the index and came out with the interesting statement by Dr. Muntz just as he had stated it. In the book it said that, "twining vines turn one way in Northern Hemisphere and turn the other way in the Southern Hemisphere." So, Dr. Muntz knew what was in his book. I don't remember whether there were any references or anything like that given, there probably was, but Bill says, "Forget it, Dr. Muntz is that way, and it not to be thought anything of." So that was that. Since then I've learned that Dr. Muntz has departed.
So you published these results in a small West Virginia journal called Castanea, I believe.
And you then continued your researches and you were just telling me you sent the second paper also to them. And what happened then.
Well, you see the first paper was sent there because the work was done at Green Bank, West Virginia. That seemed to be suitable.
So, they accepted it, with apparently some misgivings. And then I left there, and the later work was done here in Tasmania. So the second collection of evidence and its interpretation were also sent to the Editor and he politely returned it, saying that it was not suitable for their publication, and he inferred strongly that he'd been reprimanded by his directors for letting this kind of material appear in their journal, which was supposed to be devoted to survey botany, i.e., the description and discovery of plants and their habitats and how they reproduced and so on. So it struck me, though, that this was just 100 years later the kind of thing that had happened to Gregor Mendel. The chairman of the meetings, wherever it was gave his speeches was severely reprimanded by his board of directors for allowing this kind of statistical mathematical material to appear from the chair of a Botanical Society. It had no business there.
Well, let's move on to another one of your interests. Haw about the carbon dating that you did of various aboriginal remains?
Well, that had its origin in Hawaii, also. There were lava flows that ran through forests and they left sort of holes where the flow went around a large tree which ultimately rotted out. But there were shards underneath. So I went around and dug some of these up and sent them away for carbon dating. It might be expected to only get dates of a few hundred years, because all the old flows were down underneath. The dates weren't very good either, they had a very high percent error, but it gave some idea. You could probably tell one flow was earlier than another flow.
Well, that was all there was to that and I moved down here. I was just idly wandering around in Dervent Estuary and I took a boat trip down to the South Arm and got off there and wandered up about 3 miles. There was another place that the boat would come back later in the day and pick me up and take me back to Hobart. And while I was walking along I noticed there was a hill where the road department had cut a gash in the side of it, trying to straighten out a bend in the road. And this hill was in fact a sand dune. It had some grass on top, and then about a foot and a half of mixture of shells and charcoal between the top of the sand dune and the grass on the surface. And this obviously was what the archaeologists called a "kitchen midden", that is, the blacks came and fished up their shells and seafood and cooked them. These are usually pretty close to the place where they can harvest them out of the water. I scraped off maybe an inch or so of the surface to get something that might not be contaminated, but I didn't make any effort to get to the very bottom. I picked it out maybe 6 inches from the bottom. And I sent it for a date and I thought I'd get a few hundred years maybe, but much to my surprise I got a date of 2080 Ī 150, or so. Anyhow, this made it more interesting. So I enlisted help from another fellow, Max Bennett, and over the next several years, maybe three years, we visited a number of these places around the island. They are all around the seashore because the blacks have been here a long time. And the idea was quite simple.
Anyhow, the blacks lived there and we thought we'd just arbitrarily select some samples because they looked all more or less alike and how big these kitchen middens were didnít necessarily depend on the age, but rather upon how fast the shellfish grew. So we dug to the bottom of maybe 15 or 20 and got an assortment of dates. In theory we should get a random selection of numbers up to some number where there might be one or two close together and then nothing beyond that. So that would be the time when the blacks arrived. It sounds pretty simple and straightforward. So we did that l and we did get a whole collection of numbers from about 300 to 400 years out to 8,500 on one site, I think on the Carlton River and 8700 on another site, Rocky Cape, just about 240 miles away on the other side of the island and then nothing beyond that. We got several around 5,000 to 6,000. So, what we expected turned up.
Well, about this time the Australian National University instituted a new department, The Institute of Aboriginal Affairs, and they sent out sociologists to interview the live ones and archaeologists to interview the dead ones. So about this time a young man named Rhys Jones showed up, a Welshman. And he had training in archaeology, I think at Cambridge, and he'd done diggings in Albania, Greece, Finland around the coast of Norway and Denmark. And he had some experience in these matters and some understanding. So we showed him our results. We took him to a couple of places and he looked it all over and he said, "Well, this is a very good experiment, well thought out, and it is done with vigor, and you got the right answer, but itís got nothing whatsoever to do with when the blacks came." So this was sort of disconcerting. We said, "Ok, Iím on, if itís got nothing to do with when the blacks came, what does it have to do with?" He said, "Well, all you found out is when the sea rose to its present level. Any middens which were older are underneath water or most likely to have been just washed away by wave action as the sea rolls. And that these dates around eight to nine thousand or 8,500 to 9,000 are very common and they are found on all the similar kinds of places along the coast of Norway and the Shetland Islands, Scotland, Denmark. So the sea rose up the same time all over the world." And in fact, as he put it, the sea rose up in two surges, one about 30,000 years ago, apparently about 150 feet, and in a smaller surge about 8,500-9,000 years ago, maybe about 100 feet. He said, "You are wasting your time if you go fussing around with this anymore. It's true this is the first good evidence we have that the sea rose in the Southern Hemisphere, but that is to be expected."
No one had been disputing the sea level was different down here!
No. That's right.
Vines may twine differently, but the sea is at the same level.
The sea is the same level.
But this corresponds to the retreat of the last glaciers and the melting of the glaciers.
That's right, the melting of the Wisconsin glaciers of North America. It probably has some other name. So he said if you want to do things right, you get away from the sea and go hunt around inland and find some caves where the blacks may have camped. You wonít find any sea shells, but you should find bones of native animals, charcoal, that kind of thing. Well, I had a lot of other things to do and I got sort of tired of it. So I didn't do anything. Anyhow, several years passed, and rather recently, maybe about a year and a half ago, a woman, also trained in Europe, came down here from the Institute of Aboriginal Affairs. She found a nice cave on Robbins Island, northwest part, an off-shore island, a rather small island. At the time the aborigines camped there it was not an island, it was just a hill. Now it's an island since the sea rose. There was a nice cave in there, since it's sort of remote and protected from vandals and other people. We found some caves, incidentally, and they had bones in them but they were sheep bones. So the caves we found were current. Anyhow, she had her samples carbon dated and it came out something around 12,000 years. So Rhys was right, if you get away from the seashore and find the right cave, you can get older dates. And that again isnít particularly surprising because there are many sites on the mainland where the dates of 20,000 years ago, and inferences back about 25,000 years are available. So man has been here in Australia far longer than heís been in North America.
And this was in the mid Ď60s that you were doing this?
Let me ask you a general question. You seem with no fear whatsoever love to rush into a completely different field and just do it without having to worry about any background.
Well, you can spend a lot of time learning, it's true. But we did waste our time. If I had read a lot of literature and learned about all this beforehand, I may have never done it because I would have been convinced that what we were doing was a waste of time. So, ignorance is bliss.
But you are willing to take that risk essentially?
Sure. It was good fun. People say, "What are you doing that for?" and I say, "Look it, this is a lot more fun. It's intellectual, it's stimulating, you get out in the fresh air and see new and interesting places and meet new and interesting people, and all you do is club some poor little of white ball around the golf course. I think it's disgraceful."
Ok, let's move on to the other main area, I think, that you worked in, namely cosmic rays. How did you get involved with them?
Really, I don't know. But they had a Cosmic Ray Department at the University of Tasmania and I watched what they were doing. I looked at some of their results and they were doing harmonic analysis on their results, and I thought it might be possible to use this same data and handle it differently.
This is harmonic analysis on the time of arrival of...?
Of cosmic ray particles. In other words they had a lot of statistics, so many cosmic rays per minute, that all the different minutes in the hour and all the different hours in a day, and so on.
Using Geiger tubes?
Yes, using Geiger tubes.
Well, you must have been thinking about cosmic rays because of your ionosphere work.
Oh, perhaps, to some extent. Anyhow, I took this data and handled it as you would handle a random set of voltages fed into bandpass filters. And then adjusted it so that one filter had a period of, I think, 24 hours even, and another had a filter of 23 hours and 56 minutes, 23 hours 52 minutes, and 23 hours 48 minutes, 24 hours and 4 minutes.
Well, anyhow, when the data was fed into this system, it turned out that all we got was a lot of random numbers that averaged out to nearly a straight line on four of these. But the 23 hours and 56 minute one showed a definite hump in one place and a definite minimum in the other one. I think we had 7 years of data, each year was handled separately and then they were all combined. And the combined one was fairly interesting. So it looked as though maybe it was the sidereal component in cosmic rays, that is, a component fixed to the sidereal universe.
Were you doing these computations by hand?
Pretty much. We didn't have any machinery. I hired some kids at the university to work the data over and showed them what to do. They didn't know what they were doing, but they were getting paid. So, this got published in the Journal of the Franklin Institute about maybe 1965. Well, this sort of confirmed what the harmonic boys had shown, but did a little better in the sense that it was possible to get an idea of the number of particles associated with the sidereal component. It was a very small fraction, about a 10th of 1 percent of the total count. Anyhow, it turned out to be about one particle per minute per steradian per square meter. This is very small. So that's the reason it took seven years to even begin to show the phenomenon.
I didn't do any more on that. It didnít seem profitable, that is, the technique wasn't much good, really, that is, with 50 years' data we'd have done a little better, but not a whole lot better. You need something much better. Thinking the whole thing over, it seemed that energy information contradictions were here, that is, these cosmic rays particles have tremendous energy, many millions of electron volts. And so if there were many particles, there would be a tremendous flux of energy. So a priori there has to be very few particles. This means you're only going to have a few events to deal with. So instead of trying some averaging technique that had been tried in the past, where you have all your tremendous number of events to average, we should try to learn more out of each event. In other words, get more information out of each event. This meant that each particle should be individually examined for energy and direction of arrival. With the cosmic ray Geiger counter technique this is not possible.
So what was the best solution to this problem?
It was necessary to get more information about each individual particle. And this can only be done in a bubble chamber. I was now at Ohio State University and I made contact with the Physics Department, and with the the Argonne National Laboratories where they have a big bubble chamber. It turned out this was very fortunately oriented, in that it was about a meter in diameter, about 60 cm long, with the axis east-west. So, this then looked out on the meridian, that is, the plane through the north of zenith to south. And so I had a meridian transit cosmic ray telescope. And there were four cameras for stereo viewing the traces inside the bubble chamber. And there were vast quantities of photographs already available, because they run this chamber day-in and day-out, night and day as they fire into it stuff from their synchrotron.
Well, these traces of the cosmic rays looked like meteor traces across a photographic plate taken in the night sky. But we know the curvature of a trace from measurement and we know the magnetic field- that gives us the energy. So we now know the direction of arrival of the particle and its energy. So it's now possible to divide the particles up. So they were divided up from about 109 to 1010 electron volts, that's a billion to ten billion, 1010 to 1011, and 1011 and up. And I don't remember exactly how many particles we had. Altogether we had several hundred particles. So then we analyzed particles from the first group. I think we divided them up into smaller groups than that. I think from one to three, and three to ten, ten to thirty and so on. Anyhow, we divided them up, and into the lower energy groups, we couldn't find there was any difference in the galactic latitude or galactic longitude. So for all intents and purposes, the particles were coming in uniformly all the sky. However, when we got up to the 1011 electron volts, I think we only had 68 particles, some such small number, less than 100, it was found that a significantly larger fraction of them came from less than Ī30į galactic latitude than from above that. So this suggested that there was slight clustering from the plane of the Galaxy of particles having energy of 1011 electron volts or greater. And this got published in the Publications the Astronomical Society in the Pacific, about 1970.
Do you have any more plans to follow it up?
It would be nice, but I've got so many other things to do. I'd like to encourage somebody else to do it. And actually, according to the magazines I read, they are going to shut this alternating gradient synchrotron down. We don't need that thing, anyhow. To run this experiment, all we need is the bubble chamber. So maybe we can get organized and just run the bubble chamber alone and analyze the data. But it would be nice to do a much larger scale instead of having less than 100 particles above 1011, have, say, 1000 particles.
Well, there must be much more data that exists. That's all that you had time to analyze.
That's right. There is much more data if we could get it.
And there was one other aspect of it which you told me about, namely l after you say the way that these two brothers at the University of Tasmania, what was their name?
A.G. and K.B. Fenton.
They were using 1940s technology and you determined that it could be done better. Can you briefly describe what you did?
Well, this data I analyzed was taken by Bob Jacklyn in an old railway tunnel by Cambridge [Sullivan: Tasmania]. But the tubes in it were glass tubes about a meter long and maybe a couple of inches in diameter 5 cm or 6. They had an internal plating on the tube and a tungsten wire down on the center. This was designed by people along in the 1940s. These tubes have a very large background count, that is, the tubes are continually being activated. I inquired about that and I was told that this was due to the radioactive 40K in the glass. Well, this seemed unfortunate. You should be able to design Geiger tubes that didn't have such a large internal noise. So these internal discharges were just like the noise in a radio receiver, so we needed to improve signal-to-noise ratio by a lot, not 2 or 10, but 100 to 1. This meant you had to cut down the internal noise generated by the tube itself. So I had some proper Geiger tubes made in Japan, different pressures, and tried them out. The copper should be pretty inert, no radioactive isotopes. So the tube should be of low background count, but it didn't turn out to be that simple. Because wherever I had these tubes, they still produced a fairly high count, not as high as the glass tubes, but pretty high, maybe half what the glass tube were doing. So then there was a big vat at CSIRO Labs in Hobart and stove for cooking things, maybe about 6 feet high, 3 feet in diameter with a big steel lid. And so I hung one of the Geiger tubes in there to see what would happen. And the count dropped, not much but maybe 3 or 4 percent, compared to outside. Then I filled the vat full of water and it dropped about another 5 or 6 percent. So the effect of the water was equal to or more than the .5 inch of steel.
End of Tape 96A
Sullivan Tape 96B
This is continuing with Grote Reber on 12 March í78. So you found that water was rather effective.
Yes. So then I got the idea of putting the Geiger tube in a coal mine because coal is made out of carbon, and it should be very old carbon with all the radioactive isotopes died out long ago. And so it should be in an environment that's pretty dead. So I contacted the Bureau of Mines and they recommended a nice clean dry coal mine. So I took my equipment into this coal mine, about 500 feet or more underground, and tried it out and I got still a rather high count, not much different from outdoors. But it wasn't exactly surrounded by coal because they had mined out the coal and left rocks in the ceiling and the floor. And it appeared that radioactivity was coming out of the ceiling and the floor and not necessarily out of the coal. So that was sort of a failure. So then I thought, all right, let's try another scheme. And the hydroelectric commission had a big power station built in the side of a mountain, called Poatina. You go down a long ramp, this is a tourist contrivance. You go down there and take a look around this big power station, it's a hydroelectric system. Thereís turning around room at the end of the ramp. And they only allowed people to go down there in diesel buses. They won't let you drive a petrol car down there. So I made the necessary arrangements. First I did some observations outside the entrance to this long ramp. It was 1/4 mile long.
So I got a reference level from the background.
Well, anyhow, I put all my gear on the bus and took it down to this turning alcove, which was pretty big, maybe about 60 feet square, and the bus disappeared. And I set it up in a corner out of the way, and turned it on. And I got a very high count, much higher than outside, maybe twice as high as outside, remarkably high. And I thought the equipment had broken down, so I put another Geiger tube in and got the same answer. And then the bus came back and I loaded all the gear in the bus and went outside and checked it outside again at the reference level and got the same reference level. Then took it back inside again and got the same. So there was something about this turning alcove.
So it was pretty clear the environment was a pretty strong effect.
Yes. There was something about this turning chamber that had a very high radioactive content. And upon examining it, they had made it more pleasing by covering the bare rock wall by some kind of plaster. It seemed as though the stuff had a high radioactive content. So then I moved all the equipment out of the turning chamber and over into the main turbine hall, where you have rock walls. And immediately the count dropped to something lesser than what it was outdoors.
So that was about as much as you did on, all this business?
No. I continued while I was there. I was there for a week or more, and they allowed me to crawl around their tunnels and aqueducts and things by myself. And I found that if I put the Geiger tube near one of their big flumes, about 11 feet in diameter full of fresh water, the count dropped appreciably, which again confirmed what I had already learned in this vat, that water was inert and a good shield if you had enough of it.
But you didn't try to develop a new technique or try to measure any cosmic rays yourself or anything like that?
No. This was just an experiment to try and learn something about the background count in which the Geiger tube was immersed. So, about this time I found that they had partially dismantled the center turbine, in a row of five. These are vertical machines, maybe 25 feet high, with the turbine at the bottom and the generator up above. And the turbine wheel sits in a big steel casing, maybe only about 3 feet high. And they had somehow gotten this big heavy wheel out, and it was sitting on a wooden box in the turbine hall. And underneath were still the planks they used, and these planks were above the tail race, so this tail race had water running in it only a few inches below the planks. I decided to try and put my equipment in there and so I did. Now I had about 12 feet of water underneath and about 20 feet of steel and copper above and an inch of steel casing all around and some more heavy machines north and south. So this pretty thoroughly shielded the Geiger tube from all extraneous radiation from the walls. And the count went way down. Instead of making several counts per second it made only a few counts per minute. In other words, the counting rate dropped by at least 10, maybe 100 times. So this demonstrated that these copper tubes had a very low internal count when they are placed in an environment...
And so there are no other scientific fields that you've been involved in besides the ones we've mentioned?
Nothing that I can think of at the moment.
Well, I think that's quite enough. Thank you. That ends the interview with Grote Reber on 12 March í78 in Tasmania.