Stephen Ressler

Ride the rails to learn why rail transportation continues to thrive, two centuries after the modern railroad was introduced. Trace the origin of the standard rail gauge used in the U.S., probe the forces a locomotive must overcome to get rolling and then stop, and chart the rise of a revolutionary way of handling cargo: the intermodal container.

In antiquity, water pumps were extensively used in ships, mines, and agriculture. Investigate how these devices worked. From Archimedes' screw, to the waterwheel, to the piston pump, each had tradeoffs between flow rate, height of lift, and muscle power required.

What happens to the 150 gallons of water that the average person uses and then sends down the drain each day? Delve into wastewater disposal and treatment. Among the details you investigate are the S-shaped trap in a waste pipe and that most ingenious of plumbing fixtures: the toilet.

Delve into the history of the most potent artillery weapons in the era before gunpowder: catapults. Examine the workings of the ballista, onager, and trebuchet. Then get started on a model ballista capable of hurling a golf ball 200 feet. Analyze the machine's nylon torsion springs to ensure that they can store enough elastic energy to achieve the required 200-foot range.

No wooden roof of a Greek temple has survived from antiquity, yet we can surmise a great deal about how these impressive structures were engineered. Trace how Greek and later Roman architects covered large interior spaces with increasingly sophisticated timber roof systems.

Plunge into hydraulics, learning how force is transmitted from actuators to hydraulic cylinders through fluid-filled lines. Then use this knowledge to design and build a hydraulically powered mechanical arm that can grasp and manipulate a concrete block - controlled by four hand-operated syringes. Along the way, use 3D printing to fabricate several crucial parts.

Using the faucet as an example, study the bewildering number of ways that hot and cold water can be delivered into a sink, reflecting the challenges of designing everyday things. Along the way, consider the principles that go into a successful design: affordances, signifiers, mapping, constraints, and feedback.

Gain a deeper appreciation for the ancient world's most important construction material by following a block of stone from a quarry to its final resting place in the wall of a Greek temple. Learn how stone blocks were extracted from solid bedrock, moved many miles, and then fitted together without mortar.

Unravel the secret of refrigeration by focusing on the connection between heat, temperature, work, and energy. Then see how these thermodynamic concepts apply to the vapor-compression cycle in your refrigerator or air conditioner. Discover that a heat pump operates the same way.

Build your model ballista. Then construct two other types of catapult - the onager and trebuchet - designed such that they store the same amount of energy as your ballista. Field test all three to determine which throws a golf ball farthest. Will the winner be the weapon from the Hellenistic (ballista), late Roman (onager), or medieval era (trebuchet)? You may be surprised!