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Hot air ballooning

Here’s how you make a hot air balloon:

Take 23 yards of red and white persian silk, and sew them together in alternate strips.

Then mix:

Boil for about an hour over a slow fire, strain when cool, and mix with an ounce and a half of spirits of turpentine.

Use this mixture to varnish and seal the seams of the balloon.

Create gas to fill your balloon by combining 19 pounds of iron filings, 40 pounds of concentrated vitriolic [sulphuric] acid, and five times as much water in a barrel which is connected by a copper siphon to another barrel that is nearly filled with water. Connect that barrel to the balloon itself by a long metal tube.

(Avoid fire at all costs. And beware explosions.)

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