This story is from Texas Monthly’s archives. We have left it as it was originally published, without updating, to maintain a clear historical record.

Texas is absolutely the hottest and most insufferable state in the entire nation. Forget about Death Valley, Arizona, Nevada, Florida—none of them measures up. Texas alone has the right to be known as Number One, the worst.

This distinction has not been established merely by consensus or legend, but by scientific investigation. The proof may be found right on page 50 in a little text called Environmental Physiology, a book written by and for doctors who study how we adapt—or fail to adapt—to things like climatic conditions. I quote with italics added:

A review of worldwide effective temperature data for summer reveals that the Red Sea and the Indus Valley are the worst. In the United States the lower Rio Grande Valley and a section of the Gulf Coast are worst. These values are even worse than those for typical tropical areas, such as Devil’s Island in Guiana.

There you have it—even worse than Devil’s Island. A summer more sweltering than a tropical island’s. And that’s in terms of “effective temperature,” which is not simply the reading on a mercury thermometer, but an index that takes into account humidity and air movement as well—similar to the chill factor which combines the effects of wind and temperature. There are a handful of other similarly sophisticated indicators—the discomfort index, the temperature-humidity index, desert equivalent temperature—all of which add up to the same conclusion: Texas, all climatic factors considered, is unquestionably the hottest.

Just how hot? Well, along the Rio Grande, we’re talking about an average—that’s day and night—desert equiva­lent temperature* of 102° Fahrenheit every summer. That’s the hottest part of Texas in the hottest time of year, but it doesn’t get much cooler anywhere else. In Houston, Corpus, San Antonio—just about any place southeast of a line from Dallas to Del Rio—the average desert equivalent temperature in summer is slightly over 100°. This region, encom­passing our four largest cities and about half our total square acreage, is hotter on the average than Death Valley and the rest of California’s Mojave Desert, which average only 98.6°. The Panhandle, West Texas, and portions of North Texas are only a little cooler than the Mojave, with summer averages of about 95°.

By the familiar simple mercury reading, Death Valley’s 134° daytime high still claims the national record. But compar­ing Death Valley to the lower Rio Grande or the Gulf Coast is like comparing a sauna to a steam bath—simple mercury thermometer readings just don’t tell the story. For example, most healthy people can easily tolerate a sauna for fifteen minutes at a temperature of 170°, but a steam bath at 120° becomes too much after only ten minutes even though it’s 50° cooler.

But these scientific facts and figures scarcely begin to tell the story. Few people live in Death Valley. More than five million Texans live in an area that’s effectively worse. And for most of the summer, the heat is the single most im­portant fact of life. Its effects touch everything we do, our customs, our movements, the houses we live in, the clothes we wear, the food we eat.

“Houston’s downtown air conditioning puts out enough heat each day to boil ten kettles of water the size of the Astrodome.”

Apart from oil, which is heat in the form of “trapped” sunlight, heat has bestowed few other blessings. Not only does the summer hotness bring such commonly known illnesses as heat stroke and heat exhaustion, but, according to some studies, the heat also increases the likelihood of heart attack, cancer, and death in general. Exposure to too much sun, meanwhile, can cause sunburn, skin cancer, cataracts, and premature aging.

And our bodies are not all that’s affected. One heat illness called “heat asthenia” (something doctors say we all suffer from at one time or another) reportedly increases violence and ir­ritability and can lead to boredom, de­pression, and even alcoholism. Along this same line various studies and theories have linked the heat to higher crime rates, the impairment of learning ability, the fall of the cradle of civiliza­tion in Mesopotamia, and deficits of creativity and initiative in the character of nations, states, and races. After exploring the subject of heat for a while, one begins to wonder if, in an excessive­ly languid climate like ours, anything else matters. Each year, our battle against heat literally saps our bodies, our minds, and, as recent utility bills so clearly show, our money.

The Bigger We Grow, the Hotter We Get

Our cities have become islands of heat. In hot and miserable Texas, they are the hottest and most miserable places. Indeed, when all environmental factors are taken into account, parts of Houston have a much higher effective temperature than the lower Rio Grande or even the lower Amazon.

So many things about a city—cars, concrete, clusters of tall buildings, population density, pollution—make them insufferable in the summer. Indoors, air conditioning may help, but outside, the billions of BTUs released into the atmosphere each day by air conditioning units actually add to the outdoor heat load. “In the long run, we’re not making ourselves any less miserable,” says Dr. Irina Cechova, en­vironmental researcher with the Univer­sity of Texas School of Public Health. “Things are only getting worse.”

Scientists call the offending pheno­menon “urban heat islands.” These are pockets of extra-hot air that tend to collect and remain over or near the central city. Depending on the size of the metropolis, they can average anywhere from four to twenty degrees hotter than the surrounding countryside. The Uni­versity of Texas School of Public Health is conducting the first extensive heat island study of a Texas city—Houston. Only preliminary data are in, but the re­sults so far are astonishing.

“Our data show that in Houston, nocturnal and early-morning tempera­tures in the central and southeast parts of the city are about ten to fifteen de­grees hotter than the suburbs,” reports Dr. Cechova, who heads the study. “Last October, we found the Gulf Free­way to be up to 22° hotter than the suburbs in the late evening. The freeway and the industrial plants along the ship channel are probably the hottest loca­tions. The point is, even in our modern city, which we might expect to be well ventilated because of its location near the Gulf, we have major temperature differences from section to section.”

The effects of these “temperature differences” can literally be deadly. A study of the effects of the July 4, 1966, heat wave on Saint Louis found that the death rate due to heat was five-and-a-half times greater inside the city limits than in the suburbs. The total number of central city Saint Louis residents killed by heat that weekend: 209. A study of New York City during that same heat wave attributed 539 excess deaths to the heat. The researchers determined that 178 of these may have been caused by the central city “heat island” effect alone. The study also points out that deaths due to heat rise dramatically once the temperature passes 90°, and the normal heat-related death rate increases 75 per cent at 100°. Most of these heat-related excess deaths are caused by heart failures, but a recent Environmental Protection Agency study has concluded that cancer deaths rise too.

It is not the sun itself which causes the problems. In fact, heat from the sun is actually less intense in the city; urban areas receive 20 to 30 per cent less direct solar radiation than rural areas. But this is at best a small comfort. Cities get less sunlight largely because of air pollution, which actually adds to the urban heat load through what scientists call the “greenhouse effect.” The best way to understand the greenhouse effect, if you do not already understand how a greenhouse works, is to think of the pollution layer (and the atmosphere) as both a shield and a blanket; although it can reflect heat from the outside like a shield, it also keeps heat in like a blanket. The more the pollution, the thicker and more wind-resistant the blanket—and the hotter the city. Scien­tists have yet to determine exactly how much pollution adds to the thermal burden, but they are certain that it does increase urban temperature miseries.

What really intensifies the effect of urban heat is the way a city is built. Clusters of tall buildings reduce breezes by as much as 65 per cent at street level. Meanwhile, window glass reflects and intensifies heat and sunlight. Some measure of the possible extent of this effect is the increase in air-conditioning bills the mirrored United Gas Building brought to its downtown Houston neigh­bors—a hike building superintendents estimate to be ten to fifteen per cent.

But it’s concrete that really makes the difference. Concrete is one of the best heat absorption surfaces known. Most buildings exposed to sun are at least twelve to fourteen degrees hotter than even unshaded grassy areas; furthermore concrete streets and stone or steel buildings don’t cool off nearly as fast as grass, either.

The result is that a city full of con­crete stays hot at night—just when you’d expect and hope for some relief. A recent study of urban and rural temperature differences for Dallas County showed that despite all the added heat-producing factors, the city is only slightly hotter than the rural areas dur­ing the day—but around 7 p.m. the rural areas start cooling off while the city just stays hot. By sunrise, this dif­ference has reached its extreme. Such urban and rural differences have aver­aged ten to fifteen degrees in studies conducted in summer and fall.

In addition to sun and pollution and city structure, industrial and commercial activity contribute to the heat load. One heat-producing machine is the very device designed to eliminate heat—the good old air conditioner. The wonder gas that absorbs heat and makes cooling possible is Freon. But Freon must be pumped through the coils of the air conditioner inside, and that’s the role of the heat-producing compressor outside.

Although environmental researchers recognize that air conditioning makes cities hotter, there have as yet been no complete, systematic studies of its total effect. But some idea of air condition­ing’s effects may be gleaned from a look at Houston, the self-proclaimed air-conditioning capital of the country. According to the Houston Chamber of Commerce and air-conditioning industry officials, a conservative estimate of the total air conditioning necessary to cool Houston’s downtown office buildings would be in the neighborhood of 150,000 tons. This estimate includes some units like the typical 3-ton units found in most average-sized homes, but mostly units like the 4500-ton installation that cools One Shell Plaza. Not included are the 50,000-ton plant at the “suburban” Greenway Plaza complex or the 6600- ton plant at the Astrodome. It takes about 26,000 BTUs of heat energy to produce each ton of air conditioning. But each ton also gives off about 12,000 BTUs of heat from its compressor. The result is that while Houston’s 150,000 tons of air conditioning cool the city’s office buildings, they also put out about 1.8 billion BTUs of heat. And that’s each hour. For an eight-hour day, the total is an astronomical 14.4 billion BTUs or enough heat to boil ten kettles of water the size of the Astrodome.

Where does all this heat go? That’s right, straight up into the atmosphere. But not too high up. Remember the “greenhouse effect.” Well, all the pollution, which these 150,000 tons of air conditioning increase by using over 31 billion BTUs of power and energy each eight-hour day, has the effect of keep­ing the heat bottled up near the surface for all of us to feel.

The people who get it the worst are core city residents, especially the poor who can’t afford to have air conditioners in their homes. But air conditioning doesn’t just make it harder on the have-nots. People who do have air condition­ing may find that it is reducing their natural capacity to acclimatize—which is the process that makes possible the tolerances of extremes. But acclimatiza­tion only occurs through exposure—not too much exposure, but gradually in­creasing amounts. If we stay in air con­ditioning all the time, we won’t get any exposure. Except, that is, on jaunts out­side, and then the heat is a shock. This problem is of particular concern to Dr. Cechova and her research associates at the UT School of Public Health.

Does this mean that we’re no longer tough enough for our environment? Or does it mean that our environment is just too tough for us? Cechova says there’s not yet enough data to tell. But whichever proves to be the case, we’re plainly beset with problems. Fortunate­ly, some possible, partial solutions exist.

“Urban designers should give more consideration to the necessity of larger green spaces in the modern city,” says Cechova, who also teaches environmental planning at the Rice University School of Architecture. “Most parks available to city residents are not big enough to offer sufficient protection from heat stress. Another problem has to do with the way apartment complexes are built. There’s a lack of greenery and a lack of air flow. It’s a frying pan. You’re frying in your own fat. It’s in­sane.”

Battles for more green space and better urban planning are hard fought and even harder won. Scientists have at least recognized some of the problems and have begun to search for solutions. What’s discouraging is the realization that so much of the urban heat problem stems from factors apparently insepar­able from the city itself—concrete, tall buildings, pollution.

It is possible that the shared misery of the increasing urban heat load may finally precipitate some future change. Meanwhile, it’s a safe bet that all the urban heat producers from concrete to air conditioning will simply continue to increase, making cities in the nation’s hottest state ever hotter as they grow. The only consolation is that if and when we switch from fossil fuels to solar power, we may find that nature’s heat source has given us more solar energy than oil. If, that is, the sunlight can manage to filter through the pollution.

Living With the Big Heat

Exposure to a typical Texas summer can lead to cramps, burns, stroke, exhaustion, heart attack, cataracts, and cancer. It can speed up the aging process and addle your brain. It can make you eat more and urinate less. It causes “sludgy” blood, a decrease in blood sugar, an increase in oxygen consump­tion, and, of course, dehydration. Your pulse rate will rise and so will your body temperature. Your fellow human beings present more of a threat, since crime rates soar in the summer. You will probably be more violent and more irritable (if you’re not already too worn out), and you may well find that the sheer monotony of the heat brings on boredom, depression, and alcoholism.

But despite such dangers, it is pos­sible to survive and actually become more comfortable and productive in only ten to fourteen days—without air conditioning. This is possible primarily because of acclimatization. Acclimatiza­tion works through exposure to heat: the more you get, the more you can take. Up to a point, that is. The most important thing to realize is that ex­posure to excessive heat and excessive sunlight can be serious, and potentially even fatal. And, contrary to popular be­lief, a normal sunbath can be more harmful than some extreme heat con­ditions. If this sounds confusing, con­sider the sun for a moment.

Heat from the sun starts out as violent explosions within its core, millions of massive reactions with a single result: the conversion of hydrogen to helium. The sun does this over and over, con­suming some four million tons of hydrogen per second. The energy from this “waste” is what heats our solar system and stokes the sun’s 36-million-degree inner furnace. Fortunately, only a few billionths of it gets the 93,000,000 miles to earth; the rest is diffused in space.

About eight minutes after leaving the surface of the sun, this heat energy smacks into the earth’s atmosphere. Part of this energy we can see—the light that breaks down into the spectral colors (red, orange, yellow, green, blue, indigo, violet). What we can’t see are X-rays, ultraviolet light, and infrared rays, all of which would be lethal if not ade­quately filtered. The ionosphere, begin­ning about 25 miles up, mirrors back the X-rays. The ozone layer, fourteen miles up, absorbs and reflects the ultra­violet rays. The rays that filter through are what we experience as sunlight and what give us sunburns and tans. The infrared waves, most of which are ab­sorbed by the water vapor in the atmos­phere, are what we feel as heat.

But sunlight, in the form of ultra­violet rays, can do much worse things than burn—it can also cause skin can­cer and cataracts. These effects are what scientists call “photochemical” as opposed to “thermal.” In other words, they have nothing to do with how hot it is and everything to do with how much light there is; that’s why sunburns, skin cancer, and cataracts occur among snow skiers as well as sunbathers. Prop­er tanning provides some protective shield from ultraviolet rays, but it is not a sign of health. In fact, besides running the risk of skin cancer and cataracts, habitual sunbathers also accelerate the “aging” process of their skin; they make themselves look prematurely old. Al­though sun can help clear up some skin diseases like acne, dermatologists almost unanimously caution against “excessive” exposure to ultraviolet rays.

Heat, as opposed to direct sunlight, may be experienced for longer periods by healthy people not yet adapted to it. Such exposure, if properly conducted, can even make you healthier, more comfortable, and more productive. Correct acclimatization takes only ten to fourteen days and, unlike air conditioning, is free. The best way to accli­matize, according to a study reported by Dr. G. E. Folk, is through 100 minutes per day of treadmill work at a room temperature of 120°. Two such daily exposures do not speed the process, three exposures are too many. In the event you do not have access to such work/temperature conditions the next best thing is to design a similar routine for yourself that takes account of the specific heat and activity to which you want to adapt. Don’t worry if you seem to begin sweating more instead of less. That’s supposed to happen—it means your sweating mechanisms are adjust­ing to produce more sweat to cool you faster. Fortunately, acclimatization also causes a drop in the salt content of all this increased sweating, thus helping the body conserve precious sodium chloride.

As the acclimatization process goes on, heart and blood circulation will also improve, pulse rate and body tempera­ture go down, and you will thus actually become healthier. Finally, and not of small importance, you will be more physically at ease. The boredom, depres­sion, and mental lassitude of heat as­thenia will begin to creep away.

Sounds wonderful, doesn’t it? It is. Acclimatization makes it possible for people to adjust to working conditions in mines and deserts that are constantly above 100°. By virtue of acclimatization, men have been able to survive days in the desert without water, and to tolerate temperatures as high as 200° for several hours. Specially clothed men have even endured 450° to 500° temperatures. But before you get carried away with how much heat you can stand, remember your degree of acclimatization is directly related to the conditions of exposure. Just because you’re adapted to playing golf at 103° doesn’t mean you can play tennis at 98°. You have to acclimatize with specific attention to specific task and temperature conditions.

Finally, all of this applies only to healthy people and immeasurably less to women. For some reason, women can’t take heat as well as men, accord­ing to Drs. B. A. Hertig, Frederick Sargent, and others. Nobody is sure why. It appears that females simply have a lower capacity for sweating even though they have more sweat glands. If that sounds confusing, it’s mostly be­cause few studies of feminine physiology ever get done. If you happen to be a woman, the important things to remem­ber are (1) that it is natural for you to look cooler and drier than men even though you actually feel worse, and (2) you can acclimatize, although it will probably be somewhat more difficult.

There is but one final climatic twist. Bad as all our impenetrable heat and urban heat islands may be, early results of research at the University of Texas School of Public Health in Houston sug­gest that Texans actually may have more to fear from our northers. Why? Because we’re even less well adapted to cold and rapid drops in temperature than we are to heat. But that is a story for January, not August.

Does the Heat Make Us Dumb?

Summer heat literally penetrates the entire human organism. Its physiological effects can range from simple ex­haustion to severe heart attack, and have twice the impact of cold weather on the human body for each degree removed from the comfort level. Its reputed consequences on the mind are even more wide ranging and profound; but doctors simply have no accepted notion of what causes the vast syndrome of social and psychological misfortune they have labeled heat asthenia. Much more is known about the cause of physio­logical problems.

The difficulty begins with the fact that we are homoiotherms. This means we have a constant “normal” body tem­perature—good old 98.6°—and a body which attempts to maintain that tem­perature under both hot and cold conditions.

Our most important cooling mechan­ism is sweating. Few other mammals sweat, and it’s part of the reason we can take more heat than dogs and cattle. Some researchers say sweating starts to occur when outside temperatures reach 86°, but this figure varies depending on an individual’s acclimatization. Exactly what triggers the thousands of eccrine sweat glands—temperature receptors in the skin, temperature receptors in the brain, or both—is a subject of medical debate, but their effect is not: the fluid brought to the surface cools the body by the familiar process of evaporation.

Meanwhile, depending on the tem­perature, two other less crucial body cooling mechanisms may be in action. These are panting and vasodilation. Panting transfers heat from the body by exhalation. Vasodilation is more com­plex and involves an actual swelling of the blood vessels to increase blood cir­culation (which accounts for the “flush” of heat), then transfers heat from the body to the environment by convection, using the skin as a conductor. In tem­perate climates, panting accounts for about 50 per cent of total body cooling. Vasodilation and sweating account for about 25 per cent each.

But there’s a catch. Panting and vas­odilation are effective only if the temperature outside is lower than body temperature. Once the outdoor temperature reaches 95°, body and environ­ment are effectively at the same level; panting and vasodilation no longer function. Above 95°, the body actually absorbs heat from the environment. Sweating is all that’s left, which is why it’s so important.

But sweating is not perfect, either. In order for evaporative cooling to work, the atmosphere must be capable of ab­sorbing moisture. As relative humidity rises, the atmosphere absorbs less moisture. Water begins to collect on the skin, blocking further perspiration, and sweat itself adds to body heat. That’s the main difficulty in the tropics. In the dry desert air, the problem is turned around. The body sweats more and more, losing high volumes of salts and body fluids to the atmosphere. These losses ultimately take their toll on the blood: they make it thicker—“sludgy,” as one doctor puts it—and decrease the total volume available for circulation. But as the body gets hotter, it wants more blood, faster, for its cooling processes. The heat sufferer is suddenly caught in a vicious cycle and becomes vulnerable to a wide range of ill effects.

Heart Attack. Heart attack from heat occurs when the blood circulating system becomes overloaded and breaks down. This overloading can be quite common in hot climates because the body has greatly increased demands for blood for cooling as well as for performing normal activities. It is true that most studies have shown that heart attack occurs most frequently in winter months, but then most studies have been conducted in northern cities. Notable exceptions are reports from Dallas, New Orleans, and Egypt which show the incidence of heart attacks higher in summer. The Dallas study found July to be the peak heart attack month, with August second, and June third. These results at first caused some difficulties because neither of two conditions com­mon to heart attack victims—respiratory problems and increased body metabo­lism—are as common in summer as in winter. The researchers could only theorize that very hot weather, with its increased demands on the heart and the blood circulation system, was itself the key factor.

Of course, the Dallas study was con­ducted during a period (1946–1951) when air conditioning was not in wide­spread use. But studies of excess deaths in urban heat islands during heat waves also show that most of them came from heart attacks.

Heat Exhaustion, Cramps, and Stroke. These three are the most common prob­lems of overheating. Each has a differ­ent cause and character.

Heat exhaustion occurs when the body’s cooling demands are so great there’s just not enough blood to go around. In the heat, the sweat glands need more blood to work, the swollen vessels of the skin need more blood for convective cooling, while the rest of the body needs blood to carry on normally. When all this finally becomes too much for the heart and circulatory system, exhaustion—usually in the form of faintness and/or nausea, vomiting, headache, and restlessness—sets in. Contrary to some popular notions, heat exhaustion can and often does occur in the most physically fit people. In fact, what make a person susceptible to it are the excessive salt and water losses which are common in outdoor sports.

The prevention and treatment of heat exhaustion are simple and the same: rest and replacement of salt and water.

Our best known temperature regulat­ing mechanism—thirst—does not give an effective warning against heat ex­haustion. Only when dehydration has already taken a two per cent toll of body weight does thirst become violent. And by then the more severe consequences of excessive water loss—from dry throat to speech impairment and even death—are not far away.

Heat cramps involve painful tighten­ing of the skeletal muscles and all the other aches that implies. As the cure is salt and water replacement, it would seem that heat cramps result from un­replaced losses of sodium chloride. How­ever, standard medical texts acknowledge that something else—something as yet unknown—is at work because cramps are rare in low salt diet patients and diuretics.

Heat stroke is deadly. While both heat exhaustion and heat cramps are serious, it is standard medical textbook knowledge that: “True heat stroke calls for heroic measures. It is one of the few true medical emergencies.” It happens when the all-important sweating mech­anism collapses, just breaks down. In fact, that’s how you can tell if the problem is heat stroke—not heat ex­haustion—and that it’s really serious: the victim is not sweating. If left untreated the person will die. If not treated promptly, he or she may suffer damage to the brain and central nervous system. The brain literally bakes.

In really hot weather, heat stroke can occur within a few minutes after sweat stops flowing. This should be time enough to prevent it, except the vic­tim usually doesn’t know what is hap­pening. There’s usually old sweat on his skin, and he is completely unaware that his entire temperature regulating sys­tem, most especially his sweating, has stopped. As his body temperature soars, though, he will probably start to feel hot and confused and might begin to stagger around. After that, it is head­ache, delirium, or coma.

The heroic treatment required is im­mersion of the victim in ice water—pronto—because brain damage and death are a function of time and temperature during heat stroke. After the victim has come to his senses and his temperature is below 103°, he can be removed from the ice water to cold water, and later, rest. His hands and feet should be massaged to get the circulation back and to revive the body’s own heat removing processes. Most people recover if treated promptly, but they often retain a low tolerance to heat.

Heat Asthenia. This is the most com­mon, the most inescapable affliction of hot, humid climates, but no one knows exactly how it works. You might think of it as a cousin of the common cold—only worse and more subtle and wide ranging in its effects. “Asthenia” is derived from the Greek word meaning “loss of strength”; this is a classic un­derstatement, for this disease has the overall effect of draining every last drop of energy from our individual and col­lective bodies.

Here it is illuminating to quote di­rectly from a medical text (Burch and De Pasquale, Hot Climates: Man and His Heart). The manifestations of heat asthenia “consist primarily of easy fatigue, headache, mental and physical inefficiency, decrease in appetite, dys­pepsia, insomnia, restlessness, irritability, general asthenia, and a disinterest in work. . . . Although calasthenia [heat asthenia] reflects mild physiologic ad­justments to a hot and humid environ­ment, the psychic disturbances associ­ated with this syndrome may themselves be incapacitating. Boredom and depres­sion may lead to involutional behavior patterns, alcoholism and a variety of other social problems. In this respect the natives of the tropics are less af­fected than immigrants to these regions.”

There you have it—boredom, depres­sion, involutional behavior patterns, alcoholism, and a host of other social problems. A sort of scientific confirmation that heat is indeed a property of the devil. On the basis of heat asthenia (or more popularized notions of the same problem), numerous scientists have speculated about how heat affects the creativity and initiative of entire nations, states, and races. The implication is that nothing much could ever come from a place where it’s insufferably hot all the time.

Other theories suggest that people who live in hot climates like ours are just plain dumber. Several studies have shown, for example, that it is much more difficult—maybe twice as tough—to retain learned material in hot weather. Over time, it must be conceded, this could make us less intelligent. One chart demonstrates just how much mental efficency decreases according to effective temperature and length of exposure. It suggests that we can think and work rather well at temperatures as high as 120° for about half an hour. But after thirty minutes, forget it. According to a study by aerospace researcher J. F. Wing, even at an effective temperature of only 90°—some 10° less than the average summer effective temperature for most of Texas—mental efficiency is cut in half.

Prevention of heat asthenia and its diverse ill effects would be easier if we really knew how it operates. Many of the symptoms may be psychoso­matic, but there are some physiologi­cal factors involved. For example, one type of calasthenia happens when excessive sweating closes up the pores of the sweat ducts. The result is fatigue, pruritus (itching due to irritation of sensory nerve endings), and mental las­situde, that tired and stupid feeling. In sick people, the job of regulating body temperature may simply become too much for the heart and the circulation. Effects of circulatory stress will then set in—fatigue, irritability, loss of appe­tite, cough, and dyspnea (labored respi­ration). If you think this sounds like a prelude to heat exhaustion, you’re right. Appropriate preventative steps should be taken immediately; they consist, es­sentially, of cooling the person with, or, if necessary, in water. More common varieties of heat asthenia—the kind of symptoms from which most of us suffer at one time or another—have no ap­parent prevention or cure other than a change of climate.

Acting on this theory, Texas school districts began to install air conditioning on a massive scale in the late Sixties. For them—and for us voters and taxpayers—the effects of heat asthenia had some rather significant economic im­plications. In the Houston Independent School District, the state’s largest, cost of air-conditioning the schools required some $46 million in bonds.

Crime. There is evidence that heat increases violence, irritability, and, on a sociological level, crime. In fact, when summer comes, the crime rate soars. Last year, for example, Houston had the highest number of major felonies, a total of 9361, as usual, in July. Ironically, December, with 9168, was the second highest month, but it’s an ex­ception because of the holiday season. The third highest month for crime was August, with 9078.

The FBI’s Comprehensive Crime Re­port also provides evidence linking crime and heat. Los Angeles—not New York—leads major cities in absolute number of crimes, while four “sun belt” states—Arizona, Nevada, California, and Florida—lead in total crimes per capita. Texas, remarkably enough, isn’t even in the top ten. As a crime center, Waco, of all places, ranks second nation­ally in per capita murders and sixth in per capita aggravated assaults; San An­tonio ranks twenty-third in per capita murders.

Obviously, factors other than heat alone are at play in the cause of crime. For example, crime rises in the summer partly because there are more young people out of school and on the street. But heat undoubtedly figures into the criminal equation, if only, as one Hous­ton police officer said, “because it makes ’em drink more beer.”

Tan Quick, Get Cancer

Despite its gift of energy, the sun—or, more precisely its ultraviolet rays—is hazardous to our health. The only pro­tection we have is the ozone layer of the atmosphere. Clothes and cold weather don’t make much of a difference. Even cloud cover lets in roughly 70 to 80 per cent of the ultraviolet rays filtering through the ozone layer. And these rays are tough: at high noon they can pene­trate anything short of zinc oxide, in­cluding (easily) the skin, causing all sorts of uncomfortable things from sun­burn and cancer to premature aging. A tan offers some protection.

The key substance in the tanning process is melanin; it is what accounts for the darkness in human skin, whether genetic or induced by the sun. In the process of proper tanning, it forms a natural protective shield against harmful ultraviolet waves. The stuff is so tough, so durable, it can outlast the body itself; because of it, even a corpse left lying in the sun will tan. Melanin is made about midway inside the skin layers in little cells called melanocytes. When ultraviolet rays strike the skin, they seem to start an enzyme action that starts the melanocytes cranking out melanin. The melanin pigment gets aboard skin-building cells, which then rise to the skin surface.

The time it takes for hundreds of mil­lions of these melanin trips to occur is the delay between exposure and tan­ning. The ease with which you tan and the general darkness of your skin is a function of how well you produce melanin—or at least, that’s what our present knowledge theorizes; much about tanning and melanin production remains a mystery.

Some doctors say proper exposure to the sun can help clear up acne and psoriasis, relieve asthma and aching joints, and help lower blood pressure and cholesterol. Sun also provides vita­min D. But the daily minimum of vitamin D can usually be obtained in the time it takes to walk outside to a parked car. Too much exposure, the kind ob­tained by habitual sunbathers, can lead to the ill effects described below. Con­sequently, many doctors contend that the only benefits of a tan are social and psychological.

Sunburn. When you expose yourself to too much ultraviolet radiation without a proper melanin shield (dark skin or a tan), an electrochemical reaction takes place inside the skin. The reac­tionary particles are ions called free radicals. The free radicals careen around inside and outside the cells of the skin wreaking damage on skin structure and on the blood vessels. The counterreac­tion on the part of these bombarded cells is to swell. The resulting redness, medically known as erythema, is sun­burn. The reason it hurts is because there’s been tangible cellular damage, millions of miniature acts of destruction that you feel as a “burn.” Peeling ac­tually goes on all the time as upper layers of skin cells rub or flake off. A sunburn speeds up the process dras­tically.

Premature Aging. Premature aging can also result from overexposure to the sun. Remember the free radicals? Well, this is more of their doing. In addition to dynamiting the blood vessels and fracturing the skin structure, the free radicals also wreck the proteins that compose the connective and elastic tis­sues of the skin. These tissues are what prevent lines and wrinkles and sagging flesh. Because of the free radicals, ex­posure to too much ultraviolet radiation can bring on a tired and haggard look even faster than increasing years. Too much sun can also create the dark blotches often associated with age; but these are less a sign of getting old than a harbinger of skin cancer.

Skin Cancer. Doctors have long rec­ognized the link between sun and skin cancer. Although there is some compli­cating evidence, the relationship is generally considered direct—the more sun you get, the more likely you are to get skin cancer. Factors such as wind, heat, and humidity can add to the prob­lem. As might be expected, skin cancer occurs most in people who work outside—ranchers, farmers, construction work­ers, longshoremen, sailors, etc.—in short, much of the Texas labor force. Not surprisingly Texans get more skin cancer than the national average.

Fortunately, the cure rate for skin cancer is high and getting higher. Most malignancies can be removed surgically if treated in time. But this is neither cheap nor pleasant. Doctors say any new growth that doesn’t go away should get prompt medical attention.

Cataracts and Other Eye Problems. Cataracts are still another possible ill effect of too much ultraviolet radiation. They consist of an opacification of the lens: an eye protein that is usually clear starts to cloud up. Dr. Ralph Berkeley, an eye specialist in Houston, says that the sun’s role in this is suggested by the fact that cataracts often begin in the lower nasal quadrant, that part of the eye next to the nose which receives the most exposure to sunlight. Another effect even more closely related to the sun, according to Berkeley, is pterygium—a growth on the white of the eye next to the pigment. It is usually yellow-cream in color, and is fed by lines of blood vessels. Cataracts and pterygium are so common—numbering in the millions each year—that doctors do not even try to keep statistics on their incidence. But Dr. Berkeley says that it is common medical knowledge that both infirmities become more frequent the farther south one gets. So, too, he says, do forms of skin cancer related to the eye.

Staring into the sun can also cause eye problems, but rarely results in blindness except during eclipses. What usually happens is that the sun bleaches the retina, in particular its rhodopsin (also called visual purple), which helps us see in dim light. This bleaching causes the bluish or purple dots that resemble the after-image of a photo flash. Such effects are usually temporary and dis­appear when the blood has time to build up more rhodopsin. Blindness results only when the sun actually burns the retina. In most instances, our sensory reactions simply prevent us from staring at the sun long enough for this to hap­pen, but during an eclipse, the mind’s fascination often overpowers common sense; then retina burns and blindness can occur.

Proper Sunning. The prevention of all these sun-related diseases from sunburn to skin cancer is simple: stay out of the sun. If you insist on tanning, do so only before 10 a.m. and after 3 p.m., the periods when that nasty ultraviolet radiation is cut in half. Don’t worry, there will still be more than enough to get a tan. Start with fifteen minutes a day. Then add five minutes a day as you go along. If you’re relatively unexposed, watch out: your skin can start burning in about half an hour even under an umbrella because of the “scatter” ef­fects of ultraviolet radiation. When first aid is required try a cool—but not icy—tub, cold cream, or a paste of baking soda and water. Blisters caused by sun­burn call for a physician’s attention, since they are vulnerable to infection. But reportedly, the best remedy, if you can stand it, is a dosage of four aspirins every three hours; this prescription will actually return the color of your skin to normal, though it may also return the contents of your stomach to the at­mosphere.

Some medical hope lies in a drug called indomethacin (now used as a treatment for rheumatoid arthritis) which may cure the sting and the redness and even the very cell damage of sunburn. We’ll see. As for tanning oils and lotions, remember that the vast majority are junk, grease, and goop—nothing else. Many of them even contain chemicals that block the sun out, like zinc or titanium oxides. What you want is a lotion or cream that contains the vitamin B called para aminobenzoic acid—PABA for short. A five per cent content is adequate. PABA actually forms a chemical bond with the skin that helps create a shield—like the melanin shield—against ultraviolet rays. Among the helpful directions for use of this wonder acid is the idea of applying it about an hour before going out into the sun in order to get the shield effect ahead of time. 

* Desert equivalent temperature is an abstract figure derived by comparing the real atmosphere to a fixed water vapor density of ten grams per cubic meter, rather than to a saturated atmosphere.

British Thermal Unit is the quantity of heat required to raise the temperature of one pound of water one degree Fahrenheit.

The Hottest Spots in Texas

Presidio reigns in the public consciousness as the hottest spot in Texas, but two other towns—Seymour (near Wichita Falls) and Laredo—hold more legitimate claims to being the worst.

On August 12, 1936, Seymour (pop. 3500) recorded the state’s all-time record high, a whopping 120°. State climatologist Dr. John Griffiths explains that “it must have been a very dry day, and intense solar radiation moved into the area upping the temperature those extra degrees.” Whatever happened, the day was certainly an exception because the normal summer maximum in Seymour is about 98°. Its average summer desert equivalent temperature (that is, the temperature when both wind and humidity are calculated) is among the coolest in the state, a mere 95°.

Laredo (pop. 71,000), on the other hand, has the hottest effective temperature and desert equivalent temperature readings in the entire nation. In summer, the average desert equivalent temperature is an unrelenting 102°, about four degrees hotter than the Death Valley average. This excessive hotness is caused in part by warm air from the Mexican desert, and in part by air from the Gulf. Laredo is close enough to the water to pick up the humidity, but too far inland to benefit from cooling sea breezes.

The West Texas town of Presidio (pop. 1050) holds no state or national records. Its claim to fame comes by virtue of the fact that it often gets the jump on the rest of the state—that is, it gets hot sooner. Most of the town’s newsworthy temperatures come in the early spring, when landlocked West Texas areas heat up faster than the Gulf Coast. But by mid-summer, the average desert equivalent temperature is only about 95° in Presidio, compared with 102° in Laredo and a little over 100° in Houston and other parts of the Gulf Coast. Expect to hear little from Presidio in the future: several years ago the weather station closed.

How the West Was Really Won

Sometimes it seems all Texas history should be divided into two parts: Before Air Conditioning and After Air Conditioning. If it has not created modern Texas, it has, more than any other thing, permitted it.

Yet, people did manage to lead bearable lives before air conditioning, and a few ascetic souls still live without it today both willingly and enjoyably.

Some of the tricks and traditions that have made this possible are older than history itself, and begin with such basics as water, wind, shade, and the simple fan. Other more complex devices appear even in the earliest human chronicles. In fact, one Assyrian merchant was close to the idea behind air conditioning as long ago as 3000 B.C. His system consisted of having servants spray water on the walls of the basement below his courtyard. The result was a primitive humidifier and evaporative cooler. In India, people would hang wet mats in their windows, setting up a sort of breeze-powered air conditioner. In southwestern deserts, American Indians dug water trenches beneath their huts, effecting still a third variation of the same basic technique.

Ice and snow came late into the repertoire because of obvious transportation and refrigeration problems. The first mention of their use in hot climates comes in the annals of ancient Rome, where emperors had snow imported from the mountains to cool their gardens in summer. Several centuries later in Baghdad, Caliph Mahdi constructed his summer palace with double walls so that snow and ice could be packed in between. Few others could gain access to such a luxury as ice in summer until the late nineteenth century.

Instead, with Renaissance Europeans in the lead, people tried to devise ways of cooling with air, water, and mechanical power. In 1500, Leonardo da Vinci built a water-driven fan for ventilating the boudoir of a patron’s wife, and later invented, among many other things, an instrument for measuring the moisture content of the air. Discoveries about the properties of heat and ways to measure it followed in Italy, England, and Germany, from the minds of men such as Galileo, Robert Boyle, Gabriel Daniel Fahrenheit, and Anders Celsius. In 1660, Sir Christopher Wren designed a gravity exhaust ventilating system for England’s House of Parliament. Two generations later, Dr. J. T. Desaguliers added a centrifugal blowing wheel to the contraption, creating the first large-scale mechanical cooling system in history.

One of the first Americans to come up with new ideas was Dr. John Gorrie of Charleston, South Carolina. In 1833, he cooled his yellow fever and malaria patients by blowing air over ice buckets hung throughout the hospital. A year later, Jacob Perkins of Newbury Port, Massachusetts, patented the first American refrigerator; it was, remarkably enough, a commercial failure. Finally, in 1872, Daniel Boyle of Scotland and Mobile, Alabama, the reputed “father of ammonia compression refrigeration,” invented a popular forerunner of the modern machine. By this time, other Americans were contributing ideas about home cooling. Andrew Muhl, a Waco man, even patented a semisophisticated air conditioning system as early as 1874; it involved blowing air from a forced draft ventilating system through tubes and over ice-chilled coils placed near the ceiling. That same year, New Yorker Azel Lyman patented a machine which purified, dried, and cooled the air by passing it over beds of wetted charcoal. Of course, few of these intricate contraptions ever enjoyed widespread use. Even as President Garfield lay dying in the summer of 1881, all that could be contrived to cool the White House was a cooling system that consisted of melting blocks of ice at the inefficient rate of 436 pounds per hour.

Prior to air conditioning in Texas, the pioneers found thermal relief here and there. One of the more popular ways of keeping cool was living in a dog run house. This was a house built in two halves with a spacious roof-bridged gap in the middle—a thoroughfare large enough for both dogs and air currents to run through. In the Hill Country some people built their homes with sixteen-inch-thick limestone walls; such structures could stave off both heat and cold, but when walls sweated, the house would become clammy.

In 1850, Joshua Young of Seguin came up with a unique if somewhat unwieldy idea: he designed his mansion Sebastopol with a giant, squared-off roof built to hold hundreds of gallons of water for both drinking and cooling. At the same time, other more accessible architectural features which helped relieve the heat were becoming widespread—transoms, high ceilings, big windows, and even the front porch. Balconies, especially on downtown stores, were important for the precious additional shade they provided.

The advent of air conditioning laid to rest most traditional summer customs, like sitting on the porch, exchanging wintertime rugs for straw mats, and replacing heavy drapes with airy cloth curtains. The new wonder machine was first used for human comfort in Grauman’s Metropolitan Theatre in Los Angeles in 1922. Two years later, Willis Carrier installed Texas’ first air conditioners in three Will Horwitz theaters—the Palace in Dallas and the Texan and Iris in Houston. The machines were an unqualified popular and commercial sensation. Soon air conditioning spread to other theaters and to public terminals and buildings. By the 1930s, smaller units had been developed for railroad cars. After World War II, air conditioning was everywhere—on its way to becoming a $300-million-a-year industry in Texas by 1975.

We have yet to build air-conditioned freeways or plastic domes over entire cities, but such extravagance is hardly needed. For many years now it has been a common prerogative to conduct one’s entire day without once leaving a totally air-conditioned environment. The coming of summer has required us not only to brace ourselves against the heat, but also against air conditioning itself, and has spawned the strange seasonal custom of wearing sweaters in the middle of a Texas summer.