This books now collects Gray's Popular Science columns, along with hundreds of photographs -- many of which are never-before-seen. The second volume includes mad-scientist experiments, which features dramatic, enlightening, and often daring projects, such as demonstrating the Leidenfrost effect; crushing a tomato between two small magnets to show the power of neodymium-iron-boron magnets; and creating trinkets out of solid mercury to demonstrate how the state of matter depends very much on the temperature at which it exists.

Other experiments include:

• A foil boat floating on an invisible sea!
• DIY X-ray photos!
• A bacon lance that cuts steel!
• Charging a smart phone with apples and pennies!
• And dozens more!