Feathers Heavier Than Lead
At one end of a fine balance, hang a piece of lead, and at the other
as many feathers as will poise it; then place the balance in the
receiver. As the air is exhausted, the feathers will appear to
overweigh the lead, and when all the air is drawn off, the feathers
will preponderate, and the lead ascend.
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Decorations For Sky-rockets Sky-rockets May Be Decorated According
to fancy. Some are headed with stars of different sorts, such as tailed, brilliant, white, blue, and yellow stars, &c. Some with gold and silver rains; others with serpents, crackers, fire-scrolls, and marrons; and some with small rockets and other de... Different Degrees Of Heat Imbibed From The Sun's Rays By Cloths Of
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If a line be made of good whipcord, that is well dried, and a plummet affixed to the end of it, and then hung against a wainscot, and a line drawn under it, exactly where the plummet reaches, in very moderate weather it will be found to rise above i... Easy Method Of Making A Rain Gauge
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Count Morozzo placed successively several full-grown sparrows under a glass receiver, inverted over water. It was filled with atmospheric air, and afterwards with vital air. He found, First.--That in atmospheric air, HOURS MIN. The firs... Exploding Gas Bubbles
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At one end of a fine balance, hang a piece of lead, and at the other as many feathers as will poise it; then place the balance in the receiver. As the air is exhausted, the feathers will appear to overweigh the lead, and when all the air is drawn of... Fire Globes For The Water
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To make a sun of the best kind, there should be two rows of cases, which should show a double glory, and make the rays strong and full. The frame or sun-wheel must be made thus: have a circular flat nave made very strong, 12 inches diameter; to this... Flowers Curiously Affected By The Sun And The Weather
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Dissolve 100 grains of mercury by heat, in an ounce and a half of nitric acid. This solution being poured cold upon two measured ounces of alcohol previously introduced into any convenient glass vessel, a moderate heat is to be applied, till efferve... Fulminating Powder
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Lay a square of glass on the top of an open receiver, and exhaust the air. The weight of the external air will press on the glass, and smash it to atoms. ... Golden Ink
Take some white gum arabic, reduce it to an impalpable powder, in a brass mortar; dissolve it in strong brandy, and add a little common water to render it more liquid. Provide some gold in a shell, which must be detached, in order to reduce it to a ... Gunpowder Exploded By Reflection
Place two concave mirrors at about 12 or 15 feet distance from each other, and let the axis of each be in the same line. In the focus of one of them place a live coal, and in the focus of the other place some gunpowder. With a pair of double bellows... Honorary Rockets These Are The Same As Sky-rockets Except That
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