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Transcript of interview with David Bruce Dill by Luise A. Soholt, March 13, 1975






On March 13, 1975, Luise Soholt interviewed Dr. David Bruce Dill (born 1891 in Eskridge, Kansas) about his experience as a researcher in physiology, specifically in Boulder City, Nevada. Dill first discusses his educational background in physiological research, including studies done around the world, and his eventual interest in the effects of heat on the workers of Boulder Dam. Dill then discusses the topics and findings of some of his studies, including one on heat cramps and one on the comparison between sweating in a dog and that in a human. Dill also discusses the use and purpose of salt tablets.

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David Bruce Dill oral history interview, 1975 March 13. OH-00465. [Transcript]. Oral History Research Center, Special Collections and Archives, University Libraries, University of Nevada, Las Vegas. Las Vegas, Nevada.


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UNLV University Libraries David Bruce Dill i An Interview with David Bruce Dill An Oral History Conducted by Luise A. Soholt Ralph Roske Oral History Project on Early Las Vegas Special Collections and Archives Oral History Research Center University Libraries University of Nevada, Las Vegas UNLV University Libraries David Bruce Dill ii © Ralph Roske Oral History Project on Early Las Vegas University of Nevada, Las Vegas, 2017 UNLV University Libraries David Bruce Dill iii The Oral History Research Center (OHRC) was formally established by the Board of Regents of the University of Nevada System in September 2003 as an entity of the UNLV University Libraries’ Special Collections Division. The OHRC conducts oral interviews with individuals who are selected for their ability to provide first-hand observations on a variety of historical topics in Las Vegas and Southern Nevada. The OHRC is also home to legacy oral history interviews conducted prior to its establishment including many conducted by UNLV History Professor Ralph Roske and his students. This legacy interview transcript received minimal editing, such as the elimination of fragments, false starts, and repetitions in order to enhance the reader's understanding of the material. All measures have been taken to preserve the style and language of the narrator. The interviewee/narrator was not involved in the editing process. UNLV University Libraries David Bruce Dill iv Abstract On March 13, 1975, Luise Soholt interviewed Dr. David Bruce Dill (born 1891 in Eskridge, Kansas) about his experience as a researcher in physiology, specifically in Boulder City, Nevada. Dill first discusses his educational background in physiological research, including studies done around the world, and his eventual interest in the effects of heat on the workers of Boulder Dam. Dill then discusses the topics and findings of some of his studies, including one on heat cramps and one on the comparison between sweating in a dog and that in a human. Dill also discusses the use and purpose of salt tablets. UNLV University Libraries David Bruce Dill 1 We’re talking to Dr. Bruce Dill. It’s March 13th, 1975 at nine o’clock in the morning. We’re at the Bureau of Mines building on Date and Elm. My name is Luise Soholt. I live at 200 Lakeview Drive, Boulder City. This is the Local History of the Boulder Dam, the early years of the Boulder Dam project, sponsored by the American Association of University Women. Dr. Dill, would you like to tell us about how you came to come to Boulder City? Yes. It’s rather a long story. It has to do with my association with Stanford University. I was there first in 1913 and ’14 as a candidate for a master’s degree and a teacher’s certificate for high school teaching. During that year, I had a cyst on my neck and went to the local clinic for its removal, the man who removed it was a practicing physician who graduated from Stanford Medical School (unintelligible) Wilbur. When I went back for my doctor’s degree in 1923, Dr. Wilbur was then president of Stanford University. And I renewed my acquaintance with him, in that day, presidents weren’t as remote as they sometimes are today. So, I remember that friendship after I had gone back to Harvard, and use that as an opening approach to carrying out our studies in Boulder City. Well, to pick up the story of my arrival at Harvard, I was given a National Research Council fellowship in chemistry to work at Harvard, and there, my chief was L.J. Henderson, whose interests at that time were largely in physiological and biochemical studies going on down at the Massachusetts General Hospital. So, he suggested that at the beginning, at least, I should work in this hospital laboratory. Men chartered that laboratory with (unintelligible). He had just returned a year or two before from a high altitude expedition to Cerro de Pasco in Peru. This had been an expedition directed by James Bacaroff, who was a professor of physiology who came from the University of England, and there were several from England, several from the United States, who took part in the study. So, this story that I heard about—the study in Peru—aroused my interest in this field investigation, and at the end of my UNLV University Libraries David Bruce Dill 2 two years on this fellowship, I was appointed as an assistant professor to directly search in the newly established Harvard (unintelligible) Laboratory. This laboratory was set up to study man in his everyday life, in exercise and work and a variety of environments. So this opened the door to (unintelligible) field studies, the sort that Dr. Bac carried out in Peru. The first field study was a high altitude study in the mountains near Redvale, Colorado, 1929. Then, in 1930, the next year, we had a study in the wet tropics of the Panama Canal Zone in Barro Colorado Island. And 1931, I was in Europe, and in returning from Europe on a ship, I read in the ship’s newspaper that there had been thirteen deaths that summer among the workmen in the Boulder Dam project. And this made me think that this would be an excellent place for carrying out studies—in dry heat of workmen. So, we began planning for this, and I wrote to Dr. Wilbur, who was then Secretary of the Interior, having taken a leave of absence from Stanford University—the request of his friend, Herbert Hoover, who was president. And Dr. Wilbur wrote the plan of our study workmen during the summer of ’32 and turned my letter over to Dr. Mead, who was then in (unintelligible) who was then the head of the Bureau of Reclamation, under which the dam project was administered. So, Dr. Mead approved the plan and (unintelligible) and sent word out the authorities here at Boulder City, and we were then ensured that there would be a place and opportunity for us here to work. We made our plans (unintelligible) putting together the necessary equipment and sent out in February of 1932. A young clinician who was working in the laboratory—John H. Talbot—John was a graduate of Harvard Medical School, had an internship at Presbyterian Hospital, and was very much interested in physiological research, and was very eager about taking a part in this study as a physician. So, John came out, flew out—and this was a little bit hazardous in those days, February, there was a snowstorm—and the flight back from Las Vegas to Salt Lake City, pilot followed the railroad, got a little altitude and UNLV University Libraries David Bruce Dill 3 followed the railroad all the way (unintelligible) 200 feet, I supposed, something like that. So, John often told that story afterwards. However, he was treated very hospitably here in Boulder City and was ensured full access to the patients in the hospital, which was then in charge of the Six Companies surgeon, whose name was Wales Haas, that’s H-A-A-S—a very capable industrial surgeon. He also found that the municipal building was being constructed then, and we were promised our space in this old building for our laboratory. Nevada (unintelligible) we proceeded with our detailed plans (unintelligible) take out because we would have to take everything that was necessary for our experiments—something about the type of experiments that we would conduct, and then also the people who would take part in the study. And everything went forward smoothly, and we came out in June of 1932, and then in a day or two, we were in a room in the basement of the municipal building equipped for our studies. How did you come out? Did you fly or drive? One man drove out—two drove out, Harold Edward, John Talbot, and the rest of us all came by rail. A different time—didn’t all come in a party—there were a total of ten here during the summer, but some came and went, and I think, perhaps, seven or eight of us—seven of us, at least, were here for the full (unintelligible) about two months. Well, Dr. (unintelligible) Talbot, first of all, made sure that there’s a clear understanding about his being able to study and (unintelligible) patients who come into the hospital (unintelligible) any sort of heat breakdown, and that went forward very smoothly. We were assigned a cabin, a house, a fireroom house, probably, which was on the edge of the desert on what is now M Street—had just been finished, and we were given the house for the summer, and we got Army cots and minimum of furniture so we (unintelligible) stove so we could do some cooking there. And this was necessary because some of our men, three of our men, subjects, had gone to La Jolla, and on a constant diet, and UNLV University Libraries David Bruce Dill 4 had established a baseline there in La Jolla where it was cool and comfortable and there was no sweating and (unintelligible) water intake and urine volume, and then moved on to Boulder City where they continued on the same diet, which they coped in this little house. And later in the summer, as they finished their first day period, others of us went on the same diet for a shorter period (unintelligible) two weeks. The major interest in this was to measure the difference in the (unintelligible) in urine in the desert versus what they had measured in La Jolla, and this was definitely, of course, salt lost in swear. So, we had a good measure of the (unintelligible) in men who were in twenty-four hour periods over the period of about two weeks (unintelligible) sodium, potassium, chloride and so on. That proved to be a valuable study, and that result was published in the Journal of Biological Chemistry. And meanwhile, (unintelligible) it was a study in the patients who came into the hospital, several came in with heat cramps during the summer. There were no deaths that summer, and this was not entirely because of the education about the needs of salt, but also because everyone was living in air conditioned quarters in Boulder City that summer. This meant that while they did excess a great sweating during their eight hours of week and going and coming once they got to Boulder City, they were in air conditioned dormitories and ate in air conditioned mess hall. And mess hall was where we would eat, and we were charged thirty-five cents a meal for our food at that time. We refurnished the cabin so the (unintelligible) was very economical, and there was very little costs other than the rails there, too, from the east. That’s what made it possible today (unintelligible). But one observation we made during our first days was that there was a big sign in the mess hall, “The doctor says drink plenty of water,” and we persuaded him that he should add a phrase to that: “and put plenty of salt on your food.” And this was certainly, I think, surely had something to do with the fact that the men, the (unintelligible) men who had developed heat cramps or any other form of illness UNLV University Libraries David Bruce Dill 5 during the summer—those who developed heat cramps often were unusual in one way or another. That is, some would go off on a weekend binge and not be much with alcohol for two or three days, so they’d be quite depleted in salt and come back and go to work and then perhaps develop the cramps. Others were men who were on the job for the first time and wanted to try to (unintelligible). But men who ate regular meals and actually became (unintelligible) and were able to work without any serious breakdown. We carried out other studies; we had a (unintelligible) dog we had picked up at the pound in Las Vegas, and one of the men decided we should do some metabolism experiments, or particularly measure water change in the dog. So, for that purpose, we had to have a cage of some sort, and went—someone advised us to go to the yard where captured stills were stored—it was (unintelligible) Prohibition period, and it was illegal to distill your own liquor at home but we found a copper still there that was about thirty inches or so in diameter and thirty inches deep probably, with a cone-shaped top and (unintelligible) copper. And we took that, turned it upside down, put a wire screen over it, and a dish under the funnel at the bottom so we were able to—had all the necessary facilities for collecting urine from the dog, provided him with what water he wanted to drink, his food, and started a twenty-four hour experiment one morning. And no urine during the day, and when we came in the next morning, there was still no urine. So, we decided the dog was housebroken and thought he was in the house and waiting to get out. So, I decided to try a simple experiment; we had an equivalent of our modern squeeze ball—(unintelligible) ball, we called it—and I directed a stream of water onto these peanuts, and he looked around, saw the water dripping, and decided he couldn’t wait any longer. So then we collected about a half a liter of urine he had been holding. Then I took him on an all-day walk one time that’s proved to be very instructive. We laid out a course which brought us back to the laboratory about every hour-and-a-half, and I had UNLV University Libraries David Bruce Dill 6 him on a leash so he would walk about the same distance I did. And what we found was, when we came back for a drink, he drank enough to restore his body weight each time, whereas I never satisfied my thirst, but I kept losing weight. And at the end of the day, I think I had lost about three kilos, and he had lost hardly anything. And this, we interpreted, as being due to the fact that the dog (unintelligible) distills water from his mouth (unintelligible)—no sweating and no sweat glands except in his paws and his nose, and so he was losing virtually no salt. And if you accept the theory that change in osmotic pressure is responsible for thirst as a result of sweating, then the dog wasn’t losing salt, and to restore his osmotic pressure, he merely drank what he had evaporated, whereas a man is losing salt and he drinks less than he loses in sweat. Well, that made a very interesting and significant story that was published in the American Journal of Physiology. We didn’t get acquainted well with a large number of people. They essentially were busy in the laboratory most of the time, and there weren’t any social activities that we were aware of (unintelligible)—I’m sure there were, but we weren’t involved in them. The most colorful man that we got well-acquainted with, Marty was his first name—I don’t know what his last name was—and he was the janitor and caretaker of the municipal building. And he had some, I think he was probably deputized, so he carried a gun. And he was an old timer that had been around the desert for a long time, and he had great stories to tell with all his telling of stories—some true, perhaps, and some not—but he was a great source of entertainment, and we never forgot him out of the picture (unintelligible). I remember one incident that summer that greatly entertained him—Amy (unintelligible) was in our heyday then, if you’ve heard of her. Yes. And during the summer, she had disappeared for a few days and turned up on the streets of, I think it was Phoenix, a place in Arizona, (unintelligible) Tucson. The story that she had been UNLV University Libraries David Bruce Dill 7 abandoned, left far out in the desert and she didn’t know what had happened to her. But (unintelligible) the reporter who told the story noticed that she was wearing, well-dressed in white clothes and white shoes, and she showed no signs of having been in the desert. So (unintelligible) thought that was a great story, and he loved to elaborate on that and speculate as to what might have been happening to Amy. We came in, went into Las Vegas occasionally, but none of us were gamblers or drinkers, so we didn’t spend a lot of time there—there wasn’t much to be seen anyway unless (unintelligible). The Union Pacific Railroad station was a landmark, and there was a green park around it, and this being the Depression period, there were usually men sleeping there in the park at night and sitting there in the daytime waiting for help. One of our scientists who came to work with us was from Germany; he would come over on (unintelligible) fellowship to spend a year in our laboratory at Harvard, and since he was arriving in the summertime, we invited him to come on out to Boulder City. His English was all right—he could make himself understood—but you still had a lot to learn about American ways. And we hadn’t learned exactly when he was coming, but we had told him to look for the laboratory in Boulder City when he did come and to give us a call. But it developed that he arrived on the Fourth of July, and our entire party had gone off to the North Rim of the Grand Canyon for the Fourth of July weekend. So he arrived at the railroad station and went right across the street to the hotel that’s still standing there as part of the casino, which is on the corner of Main and Fremont Street, and got a room there waiting there. Well, he couldn’t establish contacts with us, and he kept asking the people, “Where’s the (unintelligible) laboratory?” which had been the (unintelligible) laboratory in Boston. So, he had a very sad story to tell there—he had never experienced heat such as that, the hotel wasn’t air conditioned. And what he remembers most about it is that his feet were miserable, and he was in his bare feet during the day just in the hotel UNLV University Libraries David Bruce Dill 8 there, and washed his socks off and remembers drying them in the window. Well, we made contact with him when he came back, and he was a physician, a clinical investigator, and he worked with John Talbot on the patients. We had some other trips; went some distance down the river—it was probably down what is now past Nelson and Eldorado Canyon to Nelson’s Landing where the river was—where there was good swimming at that time in the river and we had a good swim there. And beyond that, I don’t recall that we took many trips. We only had one car—rented another on occasion. Well, we—let’s see, I don’t think of anything else unless you have some— Did you actually use salt tablets or just (unintelligible)? No, there were no such thing as a salt tablet, and I have been credit many times for having discovered the need for salt tablets. But we were well aware of the need for salt, but this hadn’t become a part of the indoctrination of the surgeons in this country. Empirically, it was well-known in Germany, and for generations, the German workers in the steel mills had to have salt in their beer—they drink a great deal of beer, so they got plenty of salt. The forerunner in physiological research in (unintelligible) salt was (unintelligible) and others who worked with him in England. And in that time, England had lots of activities in the hot climates, and they became well aware of the need of salt, and this was well-recognized in England, but not too much so here. Although it was known here among leading medical centers, and we came from Harvard (unintelligible) compared to look for salt deficiency and seek (unintelligible)—even then, well-recognized as being consequent to salt deficiency. But we were of the opinion that all one needed to do was to add plenty of salt to the food, and this proved to be the case that we didn’t have any cases of heat cramps that—except (unintelligible) those that could be explained by lack of acclimatization or alcohol, excess alcohol and that sort of thing. UNLV University Libraries David Bruce Dill 9 Do you know when the salt tablets were developed? I think probably in World War II is when they became very well established. There’s a lot of work, a lot of studies carried on then, and at first there was objection (unintelligible) they were often called stomach pain, and it was recognized that this was because several of these salt tablets were dissolved in the stomach and formed a concentrated solution, so concentrated that it would be irritating to the stomach. So, during World War II, (unintelligible) coated salt tablets came into use, and they were coated with a protein that retards their solution in the stomach, and they pass on through where there are enzymes, and the intestine would dissolve off the protein, and they’re absorbed, and there are no nerve endings there that were sensitive to salt. But I never used salt tablets. We did find that there was a very wide range of saltiness in sweat—this became evident then. We found many evidences of that since then. So, some people are more subject to heat cramps than others because they happen to put out very salty sweat. They are the people who need to be careful about their (unintelligible). Thank you.