The story of medical imaging, the technology that allows us to see inside the human body, is full of amazing stories. Learn how X-rays were discovered in 1895, completely by accident; how ultrasound was developed to locate enemy submarines, and how the CAT Scan might never have been built if it weren’t for The Beatles!

The art of fortification evolved along with man’s need to defend his territory from attack. There was no other reason. From hills surrounded by branches and crude fences to intricate walled cities, to impenetrable castles – the strongholds of the past echo the history of great battles for territorial control.

More than the gun, more than the billy club, it is the critical weapon in law enforcement’s arsenal. But for decades, police have struggled to stay ahead of well-equipped bad guys. Rare photos and interviews tell the story of their battle for high-tech horsepower.

Throughout history the same builders and engineers that paved man's path out of the caves and into the modern world also caused some of mankind's worst disasters. Often a huge calamity is traced back to a tiny cause, insignificant in itself, but triggering a domino effect. We'll revisit notable disasters and search for probable causes.

Public aquariums have undergone dramatic changes since inception in mid-19th century. A series of technological innovations has transformed them into virtual oceans with spectacular multi-million gallon displays. Examine the latest high-tech aquatic wonders and take a peek into their future.

First there were balloons and blimps. Then, visionaries enlarged, reinforced, and motorized them and the airship was born. The biggest aircraft ever flown, they remain one of the most romantic aerial creations. In all, 161 rigid airships were built before spectacular crashes, including the EM Hindenburg /EM , put an end to the era.

Since civilization’s earliest days, man has sought protection from those who would rob him of riches, knowledge, and even life. This is the story of the evolving systems designed to safeguard our most precious possessions, and of the enduring psychological war between protectors and thieves, each intent on outfoxing the other.

What inspires societies to create sculptures on a superhuman scale? We’ll examine gigantic statues and the monumental commitment of time, money, and talent needed to complete them. We’ll study the Sphinx, Colossus of Rhodes, Statue of Liberty, Mount Rushmore, Brazil’s Christ the Redeemer, Russia’s Motherland and the Crazy Horse Memorial.

An exploration of the rich history of one of the world’s greatest technological achievements–the harnessing of power from Niagara Falls. From the “War of the Currents”, a battle between geniuses Thomas Edison and Nikola Tesla, to the Robert Moses Plant, primed to take the powerhouse into the 21st century, we highlight its story.

To run faster, jump higher, and play longer–the ultimate goal of all athletes. But when training runs its course, science and technology jump in. Explore the history and technological advances in everything from athletic shoes to football gear. And leap into a future filled with radar-enhanced baseballs and virtual-reality stadiums.

A study of the discoveries, inventions, and technological advances that have helped us understand and predict weather accurately. From simple observations made by early humans, to early instruments such as thermometers and barometers, to Doppler radar and satellite imaging, we’ll see how man has tried to harness weather.

In antiquity, a hollow reed served as an underwater link to oxygen. As in days of old, humans still need self-contained breathing equipment for a variety of reasons–food-gathering, commercial, recreational, military, and scientific. Dive with the best as we test scuba diving’s past, and look to a future of mechanical gills.

Step up to the plate and play ball as we take you on a tour of those amazing edifices of the national pastime–baseball stadiums! From the sandlots and wooden ballparks of the 1800 and 1900s to the monolithic multipurpose stadiums of today, baseball parks have grown into technological wonders that pull in and cost millions.

A look up at the symbol of the American Century–the skyscraper, the construction of which is a triumph of engineering and capitalism. Climb to the top of the Empire State Building, Chrysler Building, Sears Tower, and World Trade Center to see how ego, money, and technology joined to build the tallest of man-made structures.

Out of the bleakness of a vast desert arose a city built on wish fulfillment and indulgence. Unencumbered by tradition or notions of good taste, for 50 years Las Vegas has taken tourists to the height of their imaginations while reaching into their pockets. Visit 11 of the world's largest hotels in the country's biggest playground.

Espionage has been used for at least the last 4,000 years. And where there are spies, you find gadgets! We focus on the last 100 years of cloak and dagger technology–from early code-breaking computers to satellite reconnaissance–and take a look at the James Bond-type gadgets of the Cold War.

“He who would become a surgeon should join the army and follow it,” Hippocrates counseled nearly 2,500 years ago. In this history of medicine under fire, we see how a small army of medics, nurses, surgeons, stretcher-bearers, and ambulance drivers, races to keep pace with the deadly advances of war.

Join us for a second look at the big earth-moving machines used to tackle the most challenging jobs on, under, and off Earth! We'll ride on specialized behemoth dump trucks, delve below sea level to view dredging equipment, and leave the planet altogether to explore earthmoving equipment in space.

Plastics are everywhere–the home, the workplace, the car, the human body, outer space, and most conspicuously, the garbage heap and landfill. Artificially created test-tube material, plastic can’t be returned to nature. Will we drown in a sea of plastic? Join us as we review this protean substance’s past and future.

From the earliest recorded account of an amputation and subsequent prosthesis in ancient Hindu writings, to a 16th-century fully articulated artificial hand controlled by an intricate geared mechanism, to today’s use of plastics and space-age materials, we chronicle the long history of prosthetic devices.

The task was monumental: Build the world's largest dam in the middle of the desert, and tame the river that carved the Grand Canyon–all in seven years! When the Hoover Dam was completed in 1935, it was the largest dam in the world. We'll reveal how this engineering wonder of the world was conceived and built.

The idea of floating to earth from great heights dates back centuries, and from the beginning parachutes combined entertainment with life-saving utility. The parachute has also played a vital role in modern warfare since WWI. We’ll see how parachute technology has made the world safer, and more fun!

Well over two million years before the evolution of modern man, his primitive ancestors were making tools. The use of tools is thought to be one of the keys to human evolution itself and it permeates nearly every aspect of history. We even measure history according to our ability to craft tools; the Stone Age, the Bronze Age, the Iron Age.

Does anybody really know what time it is? Set your clocks as we explore the relativity of time from antiquity–when man attempted to chart time with methods ranging from shadows, candles, and water–to today’s atomic clock system–accurate to within one second every two-million years.

Join us for a highly charged hour as we see why Alfred Nobel's invention of dynamite took on earthshattering dimensions as his product blasted out the natural resources that built our modern world. We also examine its impact on construction of the roads, tunnels, and dams that provide us with energy and transportation.