Take copper-flakes, on which pour strong vinegar; add alum and salt in equal quantities; set them on a fire, and when the vinegar is boiled, till it becomes one-fourth part of its...
Dissolve chalk in aqua fortis, to the consistence of milk, and add to that a strong solution of silver. Keep this liquor in a glass decanter well stopped. Then cut out from a paper...
If (for example) the number named be 72,857, you tell the person who names it to place the number 7 between any two figures of that sum, and it will be divisible by 9; for if any n...
In cutting out cascades, you must take care to preserve a natural inequality in the parts cut out; for if, to save time, you should make all the holes with the same pointed tool, t...
Add to a wine-glass half full of tincture of red cabbage a small quantity of the white of an egg, either in a liquid state or rendered concrete by boiling. The tincture will lose i...
Multiply the numbers from 1 to 12 continually into each other, as follow: and the last product will give the number required. 1 2 -- 2 3 -- 6 4 -- 24 5 ---- 120 6 ---- 720 7 -----...
You must have stands made as usual, only the rails must be placed flat instead of edgewise, and have holes in them for the rocket-sticks to go through; for if they were hung upon h...
raised up and let down by the cord coming through the outside of the box. On this glass, the spectre, (or any other figure you please,) must be painted in a contracted or equal for...
would not ascend, and there is not a part that requires greater attention than this stage of the process. One blow more or less with the mallet will spoil the ascent. The charge of...
Whatever force water may have while its parts remain together, is nothing, if compared to the almost incredible power with which its parts are endued, when they are reduced to vapo...
Confine a leech in a large phial, three parts filled with rain water, regularly changed twice a week, and placed on a window frame, fronting the north. In fair and frosty weather i...
Bring a bar of iron to a white heat, and then apply to it a roll of sulphur. The iron will immediately melt and run into drops. This experiment should be performed over a basin of...
Dissolve alum in a strong ley, and scum it carefully; then mix it up with soap, and wash your silver utensils with it, using a linen rag.
First make the cases, of about six inches in length, by rolling slips of stout cartridge-paper three times round a roller, and pasting the last fold; tying it near the bottom as ti...