WEBVTT 00:00.000 --> 00:15.000 Robert Young in a story of medical conquest. 00:15.000 --> 00:20.000 Resetting the battle to stay alive, starring Robert Young on the cavalcade of America, 00:20.000 --> 00:22.000 sponsored by the DuPont Company. 00:22.000 --> 00:32.000 A number of better things for better living through chemistry. 00:32.000 --> 00:34.000 First, here is Gain Whitman. 00:34.000 --> 00:38.000 Summer, with vacationing and long hours out of doors, is almost over. 00:38.000 --> 00:43.000 Now is the time to turn your attention to your home and prepare for the winter months ahead. 00:43.000 --> 00:45.000 We have a suggestion for homemakers. 00:45.000 --> 00:49.000 Redecorate your walls with DuPont's Speed Easy wall finish. 00:49.000 --> 00:52.000 It's inexpensive, it's economical, and it's beautiful. 00:52.000 --> 00:57.000 Yes, Speed Easy will give your rooms a restful, charming finish that can be washed. 00:57.000 --> 00:59.000 It will last a long time. 00:59.000 --> 01:04.000 Speed Easy is a resin emulsion paint that goes on easily and dries in less than one hour. 01:04.000 --> 01:10.000 For less than three dollars, you can redecorate the walls of the average room in any one of 11 beautiful colors. 01:10.000 --> 01:12.000 Use Speed Easy in your home this fall. 01:12.000 --> 01:14.000 Your DuPont paint dealer has it for you. 01:14.000 --> 01:18.000 It's Speed Easy, and it's made by DuPont. 01:18.000 --> 01:21.000 Robert Young appears tonight through the courtesy of Metro Golden Mayor, 01:21.000 --> 01:24.000 producers of the all-star picture, Weekend at the Waldorf. 01:24.000 --> 01:27.000 The DuPont Company presents The Battle to Stay Alive, 01:27.000 --> 01:31.000 starring Robert Young as the narrator on The Cavalcade of America. 01:31.000 --> 01:46.000 This is a story of conquest, of the conquest of disease, of the conquest of epidemics. 01:46.000 --> 01:51.000 Our story starts in the Dark Ages. 01:51.000 --> 01:54.000 In a village, it could be any village in Europe. 01:54.000 --> 02:00.000 The Burgermaster is speaking to one of the untouchables of the community, a leper. 02:00.000 --> 02:05.000 I forbid thee to enter into the church, the abbey, the mill, or the marketplace. 02:05.000 --> 02:06.000 Dost thou heed, leper? 02:06.000 --> 02:08.000 I heed thee, sire. 02:08.000 --> 02:12.000 I forbid thee to wash thy hands at the public fountain or to drink there. 02:12.000 --> 02:13.000 Dost thou heed? 02:13.000 --> 02:15.000 I heed thee, sire. 02:15.000 --> 02:18.000 I forbid thee to touch little children. 02:18.000 --> 02:20.000 Dost thou heed, leper? 02:20.000 --> 02:21.000 I heed thee, sire. 02:21.000 --> 02:24.000 Now take thou these gloves and this bell. 02:24.000 --> 02:29.000 Go now, away from the paths of men, away from the town and the cities, 02:29.000 --> 02:34.000 for thou art contaminated by evil spirits. 02:34.000 --> 02:39.000 Away, stay away, I come. 02:39.000 --> 02:53.000 Disease, disease, disease. 02:53.000 --> 02:56.000 It's a strange thing, hard to believe today, 02:56.000 --> 03:04.000 that the overwhelming majority of the human race died convinced that disease was caused by the evil influence of supernatural powers. 03:04.000 --> 03:07.000 Demons, invisible spirits. 03:07.000 --> 03:11.000 In the jungle days, a shadow was not a shadow, but a spirit following you. 03:11.000 --> 03:20.000 An echo was a devil keeping track of you through your sounds, and the world was a place of terror. 03:20.000 --> 03:26.000 That, that is a devil, number 677, I believe, in the primitive listings. 03:26.000 --> 03:30.000 Thank you, 677, you may go now. 03:30.000 --> 03:34.000 Don't laugh, you out there listening, even if you don't believe in devils, 03:34.000 --> 03:37.000 even if not once in your entire lifetime have you said, 03:37.000 --> 03:43.000 Laura, I feel wonderful, haven't had a backache in six months, guess I better knock on wood. 03:43.000 --> 03:45.000 Even if you've never said, 03:45.000 --> 03:50.000 Sounds like a smart move, Jim, and we ought to make a barrel of money, but I got my fingers crossed. 03:50.000 --> 03:52.000 Or this. 03:52.000 --> 03:54.000 Well, when I need a new caddy. 03:54.000 --> 04:01.000 Hey boy, give me those gloves, go away, beat it, you're a jinx, a jinx. 04:01.000 --> 04:03.000 Well, that's how it was in the old days. 04:03.000 --> 04:07.000 They believed in jinxes and they crossed their fingers and they knocked on wood, 04:07.000 --> 04:10.000 even as you and I, with one difference. 04:10.000 --> 04:15.000 When there was an epidemic of malaria or yellow fever, they didn't blame it on a mosquito, 04:15.000 --> 04:20.000 they blamed it on the devil. 04:20.000 --> 04:22.000 So much for ancient history. 04:22.000 --> 04:24.000 Or would you like a little more? 04:24.000 --> 04:28.000 Perhaps you'd like to know what the wise men were saying along about the time Columbus discovered America. 04:28.000 --> 04:31.000 In Germany, for instance. 04:31.000 --> 04:35.000 They say epidemics of disease are caused by myasmas or bad air, 04:35.000 --> 04:39.000 which appear over the earth for unknown reasons. 04:39.000 --> 04:40.000 In Italy. 04:40.000 --> 04:49.000 I say they arise from a lack of balance between the four basic properties of hot, cold, moist, and dry within the human body. 04:49.000 --> 04:50.000 And in England. 04:50.000 --> 04:53.000 What is good enough for my grandfather is good enough for me. 04:53.000 --> 04:56.000 I put my shilling on the devil's. 04:56.000 --> 04:59.000 That's what they were saying, these wise men. 04:59.000 --> 05:03.000 A hundred years later, at a Congress of Physicians, Dr. Kertcher, 05:03.000 --> 05:13.000 protege of popes and emperors, stepped forward with an incredible theory. 05:13.000 --> 05:21.000 Mr. President, my lords, gentlemen, my name, as you all know, is Athanasius Kirscher. 05:21.000 --> 05:25.000 I say the cause of this epidemic is worms. 05:25.000 --> 05:34.000 These little parasites propagated within the human body are so small, so slender, and so subtle as to elude all our senses, 05:34.000 --> 05:38.000 being revealed only by the most powerful of microscopes. 05:38.000 --> 05:40.000 Dr. Kertcher had something there. 05:40.000 --> 05:42.000 Unfortunately, he didn't know when to stop. 05:42.000 --> 05:49.000 Furthermore, I say these living creatures of disease are spontaneously generated. 05:49.000 --> 05:52.000 In other words, they have no immediate ancestry. 05:52.000 --> 05:56.000 They create themselves out of decayed matter. 05:56.000 --> 06:02.000 Of course, it has been recognized for centuries that a certain strata of animal life creates itself. 06:02.000 --> 06:06.000 Not only worms, but fishes, snakes. 06:06.000 --> 06:08.000 Who laughs, please? 06:08.000 --> 06:09.000 I said, who laughs? 06:09.000 --> 06:10.000 I do. 06:10.000 --> 06:13.000 Francesco Redi, doctor in medicine and philosophy. 06:13.000 --> 06:16.000 You do not believe these worms create themselves? 06:16.000 --> 06:17.000 No. 06:17.000 --> 06:21.000 If I told you I had witnessed this miracle many times, what would you say? 06:21.000 --> 06:24.000 I would say that you have been seeing things. 06:24.000 --> 06:27.000 I do not believe you. 06:27.000 --> 06:30.000 Gentlemen, gentlemen. 06:30.000 --> 06:36.000 Dr. Redi, I have seen worms in the blood of patients suffering from the plague. 06:36.000 --> 06:37.000 Maybe yes, and maybe no. 06:37.000 --> 06:41.000 I myself have seen these parasites spontaneously generated many times. 06:41.000 --> 06:42.000 I do not believe you. 06:42.000 --> 06:45.000 I must demand proof, senor doctor. 06:45.000 --> 06:49.000 You, Herr Dr. Redi, have you not seen maggots spawned by decayed meat? 06:49.000 --> 06:54.000 Does that mean the maggots arrive without the benefit of papa and mama? 06:54.000 --> 06:56.000 Precisely, Herr Dr. Redi. 06:56.000 --> 06:59.000 As I have said, by spontaneous generation. 06:59.000 --> 07:00.000 I do not believe it. 07:00.000 --> 07:04.000 If a piece of decayed meat all by itself can produce maggots, 07:04.000 --> 07:10.000 then why can't a dying elephant give birth to nightingales? 07:10.000 --> 07:13.000 Gentlemen, gentlemen. 07:13.000 --> 07:15.000 Dr. Redi, you are going too far. 07:15.000 --> 07:19.000 I challenge you, Herr Dr. Redi, to prove my theories first. 07:19.000 --> 07:22.000 Very well, senor Dr. Kurcher. 07:22.000 --> 07:25.000 I shall prove you are alive. 07:25.000 --> 07:33.000 And Francesco Redi went back to his laboratory in Florence, 07:33.000 --> 07:37.000 convinced that the great Dr. Kurcher had made a fantastic mistake. 07:37.000 --> 07:40.000 No living thing could create itself. 07:40.000 --> 07:43.000 His good hard common sense told him so. 07:43.000 --> 07:46.000 And yet, there remained the proof. 07:46.000 --> 07:48.000 He called in his assistant. 07:48.000 --> 07:50.000 Vincenzo, Vincenzo, we go to work. 07:50.000 --> 07:51.000 Si, senor Dr. Redi. 07:51.000 --> 07:53.000 You still have those rabbits you caught this morning? 07:53.000 --> 07:54.000 Si, senor Dr. Redi. 07:54.000 --> 07:55.000 Ah, very good. 07:55.000 --> 07:58.000 Put the dead rabbits in a cask in the sun. 07:58.000 --> 08:00.000 In one week, go back and look at them. 08:00.000 --> 08:09.000 Tell me what you find. 08:09.000 --> 08:14.000 I was a fool to let myself be trapped by that artful Dr. Kurcher. 08:14.000 --> 08:16.000 He should be proving his impossible theory. 08:16.000 --> 08:18.000 Instead, I find myself compelled to disprove his theory, 08:18.000 --> 08:20.000 or be made a laughing stock. 08:20.000 --> 08:22.000 Ah, ah, Vincenzo. 08:22.000 --> 08:25.000 Senor Tottori, the rabbits, they have maggots. 08:25.000 --> 08:26.000 Ah, so? 08:26.000 --> 08:30.000 That means dead rabbits, if left in the sun, are attacked by worms. 08:30.000 --> 08:32.000 Where do the worms come from? 08:32.000 --> 08:34.000 I do not know yet. 08:34.000 --> 08:39.000 Ah, Vincenzo, do you have more rabbits? 08:39.000 --> 08:40.000 No, no, senor. 08:40.000 --> 08:42.000 No. 08:42.000 --> 08:46.000 When I went to your kitchen a little while ago, I thought I smelled... 08:46.000 --> 08:48.000 But senor Tottori, what you smelled was my dinner. 08:48.000 --> 08:51.000 Why don't you understand this is an experimental science? 08:51.000 --> 08:53.000 I don't have rabbits for dinner. 08:53.000 --> 08:54.000 But you don't like rabbits. 08:54.000 --> 08:56.000 That has nothing to do with it. 08:56.000 --> 08:59.000 Now look, take those rabbits out of the pot. 08:59.000 --> 09:01.000 Put them in a clean cask. 09:01.000 --> 09:02.000 Set it in the sun. 09:02.000 --> 09:04.000 Then tie some fine gauze over the top. 09:04.000 --> 09:07.000 Be sure you cover it completely all around. 09:07.000 --> 09:10.000 Then go back in a week and take a look. 09:10.000 --> 09:22.000 Senor Tottori, senor Tottori, the rabbits, they have no maggots. 09:22.000 --> 09:23.000 Mm-hmm. 09:23.000 --> 09:25.000 Describe the rabbits. 09:25.000 --> 09:28.000 They are in the same state of decay as the others, but there are no maggots. 09:28.000 --> 09:29.000 Mm-hmm. 09:29.000 --> 09:31.000 And what does that prove? 09:31.000 --> 09:34.000 It proves I didn't have rabbits for dinner one night last week. 09:34.000 --> 09:39.000 It proves, idiot, that maggots are not produced by the meat itself. 09:39.000 --> 09:41.000 Where do they come from then? 09:41.000 --> 09:43.000 I will tell you in one moment. 09:43.000 --> 09:44.000 Did you see any blowflies? 09:44.000 --> 09:46.000 Oh, see, both times. 09:46.000 --> 09:47.000 With the first cask and today. 09:47.000 --> 09:49.000 Ah, exactly. 09:49.000 --> 09:54.000 In the first instance, the flies, attracted by the decaying meat, laid their eggs right on it. 09:54.000 --> 09:55.000 The result? 09:55.000 --> 09:56.000 Maggots. 09:56.000 --> 09:59.000 In the second instance, there were no eggs on the meat. 09:59.000 --> 10:00.000 See? 10:00.000 --> 10:05.000 But there were hundreds of them on the gauze, proving that the gauze kept them out of the meat. 10:05.000 --> 10:10.000 And that maggots are therefore not produced by decaying matter, 10:10.000 --> 10:15.000 but are brought through the air by flies which lay the eggs, which in turn become the maggots. 10:15.000 --> 10:16.000 Hmm. 10:16.000 --> 10:20.000 Vincenzo, lay out my best coat. 10:20.000 --> 10:23.000 Tonight, I pay a call on Dr. Kurcher. 10:23.000 --> 10:35.000 Reddy's experiment effectively proved that no living thing creates itself 10:35.000 --> 10:40.000 and helped discredit this new theory of worms as the cause of epidemic disease. 10:40.000 --> 10:43.000 But what of Dr. Kurcher? 10:43.000 --> 10:48.000 Did he really see worms, as he called them, in the blood of a man dying of a plague? 10:48.000 --> 10:52.000 If he did, he was hundreds of years ahead of his time. 10:52.000 --> 10:55.000 Hundreds of years in which hundreds of millions of lives were lost, 10:55.000 --> 10:59.000 as the plague swept over Europe and the world. 10:59.000 --> 11:06.000 The plague, the plague. 11:06.000 --> 11:12.000 In this enlightened age of the 17th century, is there nothing we can do to stop this epidemic? 11:12.000 --> 11:16.000 The plague sweeps from one country to another and from one house to another, 11:16.000 --> 11:20.000 and the one that gets it today is always just next door to the one that had it yesterday. 11:20.000 --> 11:23.000 What is the cause of this plague that brings death wherever it strikes? 11:23.000 --> 11:26.000 I am a doctor, citizen. 11:26.000 --> 11:29.000 This plague is spread by contagion. 11:29.000 --> 11:32.000 If you would escape this contagion, isolate yourself. 11:32.000 --> 11:34.000 Quarantine is your best chance. 11:34.000 --> 11:37.000 Quarantine? From whom shall I isolate myself? 11:37.000 --> 11:40.000 How do I know who's got the disease and who hasn't? 11:40.000 --> 11:43.000 Sometimes you don't even know when you have it yourself until it's too late. 11:43.000 --> 11:47.000 I can only tell you to isolate yourselves. 11:47.000 --> 11:50.000 If the plague strikes, then you must prepare to die. 11:50.000 --> 12:00.000 Thank you very much, doctor, for nothing. 12:00.000 --> 12:06.000 Yes, they found out about contagion, one of the three great causes of epidemic disease. 12:06.000 --> 12:09.000 What they didn't know was all diseases are not alike, 12:09.000 --> 12:12.000 and quarantining a house might work with measles, 12:12.000 --> 12:16.000 but wouldn't be any use at all in case of yellow fever. 12:16.000 --> 12:23.000 The millions continue to die. 12:23.000 --> 12:30.000 In 1854, less than a hundred years ago, there occurred a severe outbreak of cholera in London. 12:30.000 --> 12:33.000 The health commissioner was attacked in the newspapers. 12:33.000 --> 12:38.000 He carried his troubles to young Dr. John Snow, an expert on the subject of epidemics. 12:38.000 --> 12:42.000 John, you've got to do something. Hang it all. I don't know which way to turn. 12:42.000 --> 12:46.000 Commissioner, I've been pinpointing the addresses of those who died on this spot map. 12:46.000 --> 12:52.000 Have a look. As far as I know, it's the first time anybody's ever used a map like this in the study of an epidemic. 12:52.000 --> 12:53.000 Show some interesting data. 12:53.000 --> 12:54.000 Oh, really? 12:54.000 --> 12:59.000 For instance, over 500 people have died with an radius of 250 yards on Broad Street. 12:59.000 --> 13:02.000 Well, it just means it's contagious. They catch it from each other. 13:02.000 --> 13:08.000 I don't think so. I've checked, and many of the victims never knew, saw, or spoke to the others. 13:08.000 --> 13:11.000 No, I'm afraid we'll have to look somewhere else for the explanation. 13:11.000 --> 13:12.000 But where? 13:12.000 --> 13:14.000 I'm not sure, but I have an idea. 13:14.000 --> 13:19.000 We must find out the one object, if it is an object, that is the mutual killer of all these people. 13:19.000 --> 13:28.000 Brewery hands, bricklayers, and oh yes, I forgot to mention, a nice old lady who until this morning lived right next door to you. 13:28.000 --> 13:42.000 Next door to me? Good heavens! 13:42.000 --> 13:49.000 You are listening to Robert Young as the narrator in the dramatic story, The Battle to Stay Alive, on the cavalcade of America, 13:49.000 --> 14:01.000 sponsored by the Japan Company, maker of better things for better living through chemistry. 14:01.000 --> 14:06.000 London in 1854, plagued by an outbreak of cholera. 14:06.000 --> 14:12.000 Young Dr. John Snow, who was a cautious man with an opinion, went to the center of the epidemic. 14:12.000 --> 14:18.000 There on Broad Street, he began his investigation at the Neighborhood Well. 14:18.000 --> 14:24.000 Well, doctor, are you going to play the fine gentleman and help a poor old woman work the pump? 14:24.000 --> 14:26.000 The pump? Oh yes. 14:26.000 --> 14:28.000 I'll hold my bucket then. 14:28.000 --> 14:34.000 How do you account for the fact that you, of all your family, are the only one untouched by the plague? 14:34.000 --> 14:39.000 May happen because I don't drink what the others do. 14:39.000 --> 14:40.000 And what do they drink? 14:40.000 --> 14:41.000 Water. 14:41.000 --> 14:42.000 And what do you drink? 14:42.000 --> 14:48.000 Oh, I've got a preference for other beverages. 14:48.000 --> 14:56.000 You don't drink water and you are not ill, while those of your family who do drink water from this well are down with a cholera. 14:56.000 --> 14:57.000 I, I. 14:57.000 --> 14:58.000 And madam, I must borrow your bucket. 14:58.000 --> 14:59.000 No, I don't. 14:59.000 --> 15:01.000 I'm very sorry, madam. I must have it. Good day, madam. 15:01.000 --> 15:13.000 Come back, stop, thief. The blighter's running off with my bucket. 15:13.000 --> 15:16.000 It's unbelievable. I never heard of such a thing. 15:16.000 --> 15:23.000 Why, that pump's been there for 200 years and nobody ever got cholera from it before. It's polluted now. 15:23.000 --> 15:25.000 Polluted, you say? Well, how did it get that way? 15:25.000 --> 15:27.000 Probably from the sewage in the river. 15:27.000 --> 15:32.000 And you think anybody who drinks water from that well will come down with cholera? 15:32.000 --> 15:35.000 Would you like to try a glass? I have a sample here. 15:35.000 --> 15:43.000 No, no, no, thanks. I see one house on your map which is entirely surrounded by buildings where deaths have occurred. 15:43.000 --> 15:47.000 But nobody has died in that particular house. Now how do you account for it? 15:47.000 --> 15:49.000 That house has its own private well. 15:49.000 --> 15:54.000 Yes, but wait a minute now. What about the old lady who lived next door to me? 15:54.000 --> 16:00.000 I inquired about her myself. She was an invalid, hadn't left the house in years. 16:00.000 --> 16:07.000 That's the strangest part of all. Turns out that that old lady lived near Broad Street when she was a girl a long time ago, I imagine. 16:07.000 --> 16:13.000 She developed a fondness for water from that particular well, Silubrious she called it. 16:13.000 --> 16:18.000 For 40 years now she's had a barrel of it carted up to her place every week. 16:18.000 --> 16:24.000 I'm convinced. I'll have that pump blown up with explosives inside of an hour. 16:24.000 --> 16:28.000 Not necessary. Just take the handle off. It's quicker. 16:28.000 --> 16:37.000 That's exactly what they did. They took the handle off the Broad Street pump. 16:37.000 --> 16:40.000 From that day on that cholera epidemic was history. 16:40.000 --> 16:49.000 And so pollution, the second of the three great causes of epidemic disease, was made known to the world. 16:49.000 --> 16:54.000 First, contagion by personal contact. Second, pollution. 16:54.000 --> 16:58.000 There still remained a third great destroyer of human lives. 16:58.000 --> 17:06.000 The enigma of the transmission of disease by insects remained unsolved until a great many individual contributions were made 17:06.000 --> 17:11.000 by the men of a new field of medical science, microbiology. 17:11.000 --> 17:16.000 Men like Pasteur, Koch, and a surgeon named Lister. 17:16.000 --> 17:23.000 However, it remained for an American, Theobald Smith, working in our own Department of Agriculture, 17:23.000 --> 17:30.000 to open the door and make the discovery that pointed to another way in the conquest of epidemic disease. 17:30.000 --> 17:34.000 Smith, you ever hear of Texas fever? 17:34.000 --> 17:36.000 No, I don't think I have. 17:36.000 --> 17:38.000 Oh, wait a minute, yes. It affects cattle, doesn't it? 17:38.000 --> 17:42.000 That's it. It kills them off in about a month. 17:42.000 --> 17:46.000 Well, it's broken loose again all over the country, epidemic proportions. 17:46.000 --> 17:47.000 And what do we know about it? 17:47.000 --> 17:49.000 Practically nothing. 17:49.000 --> 17:53.000 Southern cattlemen buy northern cows and ship south. 17:53.000 --> 17:57.000 When they arrive, they're healthy. They're put to graze with southern cows. 17:57.000 --> 17:59.000 About a month later, they're dead. 17:59.000 --> 18:00.000 The northern? 18:00.000 --> 18:04.000 Yes, but that's only half of it. Northern cattlemen buy southern cows. 18:04.000 --> 18:09.000 Cows are shipped north, arrive healthy. They're put to graze with northern cows. 18:09.000 --> 18:11.000 Then what happens? 18:11.000 --> 18:12.000 The southern cows die. 18:12.000 --> 18:14.000 Not at all. The northern ones. 18:14.000 --> 18:16.000 Well, pretty, isn't it? 18:16.000 --> 18:20.000 Well, anything to go on? Any clues, any ideas, any hints? 18:20.000 --> 18:24.000 Not a thing. I'm turning it over to you. The department expects results. 18:24.000 --> 18:26.000 You can have Kilburn as your assistant. 18:26.000 --> 18:34.000 Music 18:34.000 --> 18:40.000 Before they went to work, Smith and Kilburn consulted all available expert opinion on cow disease. 18:40.000 --> 18:43.000 It was somewhat contradictory. 18:43.000 --> 18:47.000 Texas fever is spread by the saliva of the cows. 18:47.000 --> 18:50.000 Texas fever is spread by polluted water, like cholera. 18:50.000 --> 18:52.000 Texas fever is caused by bacillus. 18:52.000 --> 18:58.000 Texas fever may or may not be caused by bacillus, but it is not spread by saliva or polluted water. 18:58.000 --> 19:01.000 With this kindly advice ringing in his ears, 19:01.000 --> 19:04.000 Theobald Smith proceeded to dissect dead cows. 19:04.000 --> 19:09.000 He found millions of microbes in every one. That, at least, was definite. 19:09.000 --> 19:12.000 Next, he went out into the field. He talked to the cattlemen. 19:12.000 --> 19:16.000 Well, now there's one thing I scared them to know. 19:16.000 --> 19:21.000 Maybe you're like all those other experts, though, not interested in any opinion that ain't according to the book. 19:21.000 --> 19:24.000 I'd be more than interested in anything you've got to tell me. 19:24.000 --> 19:26.000 You won't laugh, like them others? 19:26.000 --> 19:28.000 I promise you, I won't laugh. 19:28.000 --> 19:31.000 Okay, here it is. Ticks. 19:31.000 --> 19:34.000 Ticks? You mean insects? 19:34.000 --> 19:37.000 Well, I guess a tick is a kind of insect. 19:37.000 --> 19:40.000 Anyhow, that's what causes Texas fever. 19:40.000 --> 19:44.000 Because every cow that dies has ticks. And loaded with them. 19:44.000 --> 19:48.000 Let me get this straight. The northern cows come down here. Do they have ticks then? 19:48.000 --> 19:53.000 No. Not until they graze in the same fields as our own cows. 19:53.000 --> 19:56.000 Then they get them fast. Then they die. 19:56.000 --> 20:02.000 Oh, I see. I suppose you've been told that the bite of an insect has never been known to transmit epidemic disease? 20:02.000 --> 20:06.000 Well, that's what the experts say. I only know what I see. 20:06.000 --> 20:08.000 Well, maybe you've got something there. 20:08.000 --> 20:12.000 There's one thing more. Your own southern cows. Do they have ticks, too? 20:12.000 --> 20:14.000 They got them. 20:14.000 --> 20:15.000 But they don't die? 20:15.000 --> 20:18.000 Nope. They don't die. 20:18.000 --> 20:21.000 Well, that complicates it, all right. 20:21.000 --> 20:24.000 It certainly did. 20:24.000 --> 20:29.000 In addition, as Smith said, no insect had ever been known to communicate disease. 20:29.000 --> 20:34.000 But there always had to be a first time. It was worth trying, anyhow. 20:34.000 --> 20:36.000 Gilborn, those southern cows arrive yet? 20:36.000 --> 20:40.000 Several of them. All loaded down with ticks, but otherwise healthy. What'll I do with them? 20:40.000 --> 20:45.000 Put four in field number one. With them, put six northern cows, healthy ones. 20:45.000 --> 20:51.000 Next, we take the other three southern cows and remove every tick on and under their hides. 20:51.000 --> 20:55.000 Set them down in field number two. And with them, we put four healthy northern cows. 20:55.000 --> 20:56.000 I'm listening. 20:56.000 --> 21:01.000 Then we wait. In about a month, the first batch of northern cattle will catch the ticks and die. 21:01.000 --> 21:05.000 The second four won't catch any ticks because there aren't any. 21:05.000 --> 21:08.000 Then if they die, we'll know we're on the wrong track. 21:08.000 --> 21:12.000 But if they don't, we'll know the answer is ticks. 21:12.000 --> 21:23.000 The second batch did not die, and the Texas cattlemen were right. 21:23.000 --> 21:28.000 The next step was, what kind of assassin was it that the ticks shot into the cows? 21:28.000 --> 21:35.000 Smith focused his microscope on the blood of the diseased northern sear and found a pear-shaped microbe. 21:35.000 --> 21:42.000 Here was the killer. The beer ball Smith was also a cautious man. He had to be sure. 21:42.000 --> 21:49.000 Gelburn, we've proved that four northern cows in the same field with southern cows that have had the ticks removed remain healthy. 21:49.000 --> 21:50.000 Right, chief. 21:50.000 --> 21:54.000 Has it occurred to you that these four might be immune? 21:54.000 --> 22:00.000 Well, look. Take two of those four and put them in field number one, with the southern cows with the ticks, 22:00.000 --> 22:03.000 the same ones that already killed six northern cows. 22:03.000 --> 22:08.000 If they catch ticks and die, then we'll know we're right. 22:08.000 --> 22:13.000 They caught the ticks and they died. 22:13.000 --> 22:16.000 The problem was solved, but what if? 22:16.000 --> 22:22.000 What about the other half of the riddle, the southern cows? They had ticks, didn't they? Why didn't they die? 22:22.000 --> 22:25.000 Yeah, that's what's bothering me, chief. What about those southern cows? 22:25.000 --> 22:31.000 Well, now let's break it down. As calves, they were put out to graze in fields infested with ticks. 22:31.000 --> 22:37.000 Right. They grow up into yearlings and then heifers with plenty of ticks but no Texas fever. 22:37.000 --> 22:41.000 Maybe their blood is different. Maybe they are immune. 22:41.000 --> 22:45.000 Cure, boy. I think we've got it. 22:45.000 --> 22:51.000 Suppose they got a mild dose of it when they were calves. It would immunize them. 22:51.000 --> 22:58.000 Maybe when they were young, the disease is milder and sets up an immunity like a vaccination. 22:58.000 --> 23:02.000 Hey, where are you going? I'm going to load a couple of northern calves. 23:02.000 --> 23:06.000 Calves, not cows, with all the ticks their hives will hold. 23:06.000 --> 23:12.000 If they don't die, it's the missing link. The trip will check, and then we'll tell it to the world. 23:12.000 --> 23:27.000 The calves came down with a mild attack of Texas fever, but soon recovered and lived to a ripe old age, forever immune. 23:27.000 --> 23:35.000 It wasn't only then that Theobald Smith made known his discovery to the world. 23:35.000 --> 23:46.000 Thus it was that an American bacteriologist supplied the clue to the riddle of the third and perhaps greatest cause of epidemic disease, transmission by insects. 23:46.000 --> 23:54.000 Within a few years, his discovery was made use of by David Brute, who found that the titsy fly was the carrier of sleeping sickness. 23:54.000 --> 23:58.000 By Ross and Grassey, with their Anopheles mosquito and malaria. 23:58.000 --> 24:13.000 And by a major in the United States Army, Walter Reed, who uncovered another mosquito as the carrier of the yellow fever germ. 24:13.000 --> 24:16.000 Now the story is complete. Or is it? 24:16.000 --> 24:24.000 What we know today is that epidemic disease is spread by personal contact, pollution, or by insect carrier. 24:24.000 --> 24:27.000 Of these three and only these three are we certain. 24:27.000 --> 24:32.000 But who knows if there isn't a fourth or even a fifth cause of epidemic disease. 24:32.000 --> 24:44.000 Even now, at this very moment, men of science go on peering into their cultures, seeking knowledge in the realm of the unknown, continuing man's conquest of disease. 24:44.000 --> 24:51.000 You men of science, do not let yourselves be discouraged by a deprecating and barren skepticism. 24:51.000 --> 24:56.000 Do not be disheartened by the sadness of certain hours which pass over nations. 24:56.000 --> 25:11.000 Live and work in the serene peace of laboratories and libraries, secure in the knowledge that you are contributing to the progress of humanity, and are aiding mankind in the battle to stay alive. 25:11.000 --> 25:32.000 Our star, Robert Young, will return in just a moment to our Capulcade microphone. 25:32.000 --> 25:34.000 Now here is Gaines Whitman. 25:34.000 --> 25:40.000 Dry cleaners, hard as they tried, were not able to give you the best cleaning service during the war. 25:40.000 --> 25:44.000 The reason was that their fluids were doing war work. 25:44.000 --> 25:54.000 DuPont PurClean and TriClean solvents, for instance, were cleaning oil in Greece from parts for planes and other war machines destined for Europe and Japan. 25:54.000 --> 26:07.000 But now, if you're particular about your dry cleaning, particular enough to choose the dry cleaner who uses PurClean and TriClean, you can have fast, thorough, odorless dry cleaning again. 26:07.000 --> 26:10.000 DuPont cleaning fluids are back. 26:10.000 --> 26:18.000 You know from experience that the dry cleaning fluids provided by modern industrial chemistry are better than the old-fashioned fluids. 26:18.000 --> 26:23.000 These fluids are designed by chemists just for this particular job. 26:23.000 --> 26:34.000 Quicker and more thorough, they clean your clothes so speedily that delicate garments stay in the machine only a few moments, so they don't suffer any appreciable amount of wear and tear. 26:34.000 --> 26:41.000 And these chemical fluids evaporate so quickly and completely that when the garments are returned to you, they're odorless. 26:41.000 --> 26:48.000 The fluids don't burn, they don't explode, so your clothes are much safer while the cleaner has them in his shop. 26:48.000 --> 26:57.000 And more important, safe fluids mean the cleaner can have his shop right in your neighborhood and give you much quicker service. 26:57.000 --> 27:07.000 With DuPont PurClean and TriClean back in civilian clothes again, you can enjoy once more the efficient and satisfactory cleaning you were accustomed to before the war. 27:07.000 --> 27:14.000 Yet quality dry cleaning prices, by and large, are much lower than they were 15 years ago. 27:14.000 --> 27:23.000 PurClean and TriClean dry cleaning fluids are among DuPont's better things for better living through chemistry. 27:23.000 --> 27:34.000 And now, here is the star of tonight's DuPont cavalcade, Robert Young. 27:34.000 --> 27:47.000 There's an old American adage that runs something like this. 27:47.000 --> 27:53.000 The difficult we do immediately, the impossible just takes a little longer. 27:53.000 --> 28:03.000 That may be one way of explaining the phenomenal growth of American air strength from a handful of men in planes before Pearl Harbor to the most powerful air armada in the world. 28:03.000 --> 28:15.000 Next week, cavalcade will tell the story that could not be told before, the story of the creation of the AAF, the American Air Force, the greatest striking power in the world. 28:15.000 --> 28:17.000 Pat O'Brien will be the star. 28:17.000 --> 28:46.000 Don't forget next week on the DuPont cavalcade, 200,000 Flyers, starring Pat O'Brien. 28:46.000 --> 28:56.000 Cavalcade programs of particular interest to servicemen and women are broadcast overseas through the worldwide facilities of the Armed Forces radio service. 28:56.000 --> 29:01.000 The music for tonight's DuPont cavalcade was composed and conducted by Robert Armbruster. 29:01.000 --> 29:04.000 Our cavalcade play was written by Arthur Arendt. 29:04.000 --> 29:15.000 This is Tom Collins inviting you to listen next week to Pat O'Brien in 200,000 Flyers on the cavalcade of America, brought to you by the DuPont company of Wilmington, Delaware. 29:15.000 --> 29:26.000 This is the nice little broadcast being covered.