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reached his twelfth year, appeared swimming in fire, as at every stroke flames arose all around him, darted to the gold-laced border, ran along it, and up to that of the bed, and even to the very top.
While he was showing this experiment, Prince Orloff came into the room, with a sable muff in his hand, and showed us, that by only whirling it five or six times round his head in the air, he could electrify himself so strongly, as to send out sparks from all the uncovered parts of his body.
Astonishing Power of Steam.
If you put a small quantity of water into a tea-kettle, and place it on the fire, it will disappear in a short time, having escaped in the steam. But if its escape be prevented by stopping up the spout and crevices, it will force its way by bursting the vessel in which it was confined.
If the steam of boiling water be at liberty, the water never attains more than a certain degree of heat; but if confined in a close vessel, the additional fire not escaping, the power of the steam is increased, it re-acts upon the water, and raises the heat so much higher, that it would keep lead in a melting state; and so penetrating, that it would soften the marrow-bone of an ox, in a few minutes.
There is an instrument contrived for the foregoing purposes, called Papin's Digester, from the name of its inventor, and from its digestive powers on substances exposed to its action. It is a very strong vessel, made of copper, fitted with a thick close cover, and fastened down by several strong screws, so as to render it steam-tight in great degrees of heat. To render it safe, while being used, there is a valve on the cover, to let out the steam, when it is too violent; this valve is kept down by a steel-yard, with a weight moveable upon it, to regulate the degrees of the steam within.
The following account of an accident with one of these instruments, will give some idea of the great force of steam.
Mr. Papin (the inventor) having fixed all things right, and included about a pint of water, with two ounces of marrow-bone, he placed the vessel horizontally between the bars of the grate, about half-way into the fire. In three minutes he found it raised to a great heat, and perceiving the heat in a very short time become more raging, stepped to a side-table for an iron to take the digester out of the fire, when it suddenly burst with the explosion of a musket. It was heard at a considerable distance, and actually shook the house. The bottom of the vessel that was in the fire gave way; the blast of the expanded water blew all the coals out of the fire into the room, the remainder of the vessel flew across the room, and, hitting the leaf of an oak table, an inch thick, broke it all in pieces, and rebounded half the length of the room back again. He could not perceive the least sign of water, though he looked carefully for it; the fire was quite extinguished, and every coal black in an instant.
The following accident was attended with more fatal consequences.
A steam-engine was repairing at Chelsea, and, as the workmen were endeavouring to discover the defect, the boiler suddenly exploded, and a cloud of steam rushing out at the fracture, struck one of the men who was near it, like a blast of lightning, and killed him in a moment; when his companions endeavoured to take off his clothes, the flesh came off with them from the bones.
Account of the Wonderful Effects of two immense Burning-Glasses.
Mr. de Tschirnhausen constructed a burning-glass, between three and four feet in diameter, and whose focus was rendered more powerful by a second one. This glass melted tiles, slates, pumice-stone, &c., in a moment; pitch, and all resins, were melted even under water; the ashes of vegetables, wood, and other matters, were converted into glass; indeed, it either melted, calcined, or dissipated into smoke, every thing applied to its focus.
Mr. Parker, of Fleet-street, made a burning-glass, three feet in diameter; it was formed of flint glass, and when on its frame, exposed a surface of 2 feet 8½ inches to the solar rays. It had a small glass fitted to it, to converge the rays, and heighten the effect. The experiments made by it were more powerful and accurate than those performed by any other glass. The following is a brief epitome of its astonishing power.
| Substances melted, with their weight; and the Time in Seconds, which they took in melting. | Weight in Grains. | Time in Seconds. |
|---|---|---|
| Pure gold | 20 | 4 |
| Pure silver | 20 | 3 |
| Pure copper | 33 | 20 |
| Pure platina | 10 | 3 |
| Nickel | 16 | 3 |
| A cube of bar-iron | 10 | 12 |
| A cube of cast-iron | 10 | 3 |
| A cube of steel | 10 | 12 |
| Scoria of wrought-iron | 12 | 2 |
| Kearsh | 10 | 3 |
| Cauk, or terra ponderosa | 10 | 7 |
| A topaz, or chrysolite | 3 | 45 |
| An oriental emerald | 2 | 25 |
| Crystal pebble | 7 | 6 |
| White agate | 10 | 30 |
| Oriental flint | 10 | 30 |
| Rough cornelian | 10 | 75 |
| Jasper | 10 | 25 |
| Onyx | 10 | 20 |
| Garnet | 10 | 17 |
| White rhomboidal spar | 10 | 60 |
| Zeolites | 10 | 23 |
| Rotten-stone | 10 |
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