Volume 1 / Part 7 — Making a Fire with the Aid of Ice
Reading edition
Forming the Ice Lens
Take a piece of very clear ice and melt it down into the hollow of your hands so as to form a large lens. The illustration shows how this is done. With the lens-shaped ice used in the same manner as a reading glass to direct the sun's rays on paper or shavings you can start a fire.
Contributed by Arthur E. Joerin.