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Fixing the Leaning Tower of Pisa

All in the Family

Long-Distance Doc


Where's the Matter?

Renaissance Machines
in the classroom

SCIENCE ITALIAN STYLE: Renaissance Machines

Inventions from the 15th-century come to life as Frontiers takes us into the past with the help of 20th-century technology. First we see how Renaissance engineer Filippo Brunelleschi achieved the greatest architectural feat of his day by building a dome on the Florence cathedral without using scaffolding. In 1955, drawings of Brunelleschi's secret inventions were discovered and reconstructed. With the help of a computer, we can now see some working models of Brunelleschi's machines.

Curriculum Links
Activity: Hanging in There?
Consider This!





musculoskeletal system

work, machines

design, drafting,
engineering, invention,
material science


On Frontiers, you glimpse the inventive machines of Renaissance engineers Brunelleschi and Leonardo da Vinci. Although da Vinci's human-generated flying machine didn't have the technology needed to get off the ground, some of its design elements are incorporated into today's hang gliders.

Try building the hang glider described here. Then, modify the design to create a model that can fly longer distances. Test your design against those of other class members in a hang-gliding challenge!

  • 4 straws
  • scissors
  • Scotch tape
  • plastic wrap
  • small toy figure
  • string

  1. Cut out a square of plastic wrap about 20cm x 20cm.

  2. Place two straws along the edges of adjoining sides. Fasten the straws to the plastic with tape.

  3. Place a third straw between the two straws taped to the sides. This third straw should align with the middle of the plastic. Tape the straw.

  4. Tape the fourth straw across the middle of the glider, so it supports all three straws. Trim the plastic.

  5. Tape or hang a toy figure from the middle straw.

  6. Launch the glider. You may need to make adjustments in placing the toy figure. (If the glider dives, move the figure back. If it climbs too steeply and stalls, move the figure forward.)

Once you have constructed your glider, brainstorm ways to improve its design. Build an updated model, using a variety of materials. Continue testing and improving the design until you have created the best flying model. Then, enter it in a classroom contest. Which glider flies the longest distance?

  • Leonardo da Vinci's creative genius as artist, engineer, scientist and inventor was nothing short of remarkable. Da Vinci sketched inventions in his notebooks that would not appear for another four or five hundred years, including designs for a parachute, bicycle, flying machine, military tank, diving suit, suspension bridge, as well as detailed anatomical drawings. His notes are written backwards and can be read only in a mirror, done to protect his original ideas from unwanted detection. Contrary to what was commonly believed in his day, da Vinci seemed to believe that Earth was not at the center of the universe. One line that appears in a notebook reads: "The sun does not move."

  • In the late 15th century, when da Vinci was doing engineering work for the Borgias, mathematical measurements were far from standardized. Architects and engineers used a unit of length called the braccio -- the equivalent of two palms. Other units in Renaissance Italy included the piede, the foot, and the pollice, the width of the thumb. If you think metrics is hard to master, imagine trying to design a building with such variations in measurements!


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.