Recalling Robert Stirling's invention in 1816 of a safer, more efficient alternative to the steam engine, this working Stirling engine kit demonstrates the same thermodynamic principles that powered the original. Still taught today in mechanical engineering courses to show the high efficiency, quiet operation, and heat utilization of closed-cycle regenerative heat engines, Stirling engines are powered by the expansion and compression of air. The kit serves as a hands-on tool for understanding the simple yet elegant dynamics of the seminal technology. The finished engine is fueled by an alcohol burner that heats the front of the glass tube, causing the air inside to expand and contract and push the piston toward the gears. The piston is connected to a system of flywheels and pulleys that exert reciprocal force on the piston, causing it to move back and forth. The energy produced by the desktop engine can be harnessed to spin the integrated fan, illuminate the attached light bulb, and rotate the rear wheels, propelling the locomobile forward. Assembles in two to three hours. For ages 18 and up. Can also be powered by two AA batteries (not included). 6 1/3" H x 11" L x 5" W. (2 1/4 lbs.)