A History of Inventions, Discoveries, and Origins. Johann Beckmann

A History of Inventions, Discoveries, and Origins - Johann Beckmann


Скачать книгу
be prepared; which, if swallowed by a dog or other animal, would insensibly destroy it, without any violent symptoms, in the course of some weeks or months.”

      “The effects of this poison are very simple. A general indisposition is at first felt in the whole frame. The physician examines you, and perceiving no symptoms of disease, either external or internal, no obstructions, no collection of humours, no inflammations, orders detergents, regimen, and evacuation. The dose of poison is then doubled, and the same indisposition continues without being more characterized. The physician, who can see in this nothing extraordinary, ascribes the state of the patient to viscous and peccant humours, which have not been sufficiently carried off by the first evacuation. He orders a second—a third dose—a third evacuation—a fourth dose. The physician then sees that the disease has escaped him; that he has mistaken it, and that the cause of it cannot be discovered but by changing the regimen. He orders the waters, &c. In a word, the noble parts lose their tone, become relaxed and affected, and the lungs particularly, as the most delicate of all, and one of those most employed in the functions of the animal œconomy. The first illness then carries you off; because the critical accumulation settles always on the weak part, and consequently on the lobes of the lungs; the pus there fixes itself, and the disease becomes incurable. By this method they follow one as long as they choose for months, and for years. Robust constitutions resist a long time. In short, it is not the liquor alone that kills, it is rather the different remedies, which alter and then destroy the temperament, exhaust the strength, extenuate and render one incapable of supporting the first indisposition that comes.”

      WOODEN BELLOWS.

       Table of Contents

      After the discovery of fire, the first instrument employed to blow it and strengthen it, has undoubtedly been a hollow reed, until the art was found out of forming a stick into a pipe by boring it. Our common bellows, which consist of two boards joined together by a piece of leather, and which probably are an imitation of the lungs, appear to have been early known to the Greeks. I have, however, met with no passage in any ancient author from which I could learn the oldest construction of this machine, which in latter times has received many improvements. Had I found such information, I should have endeavoured to explain it, as it would have contributed to enlarge the knowledge we have of the metallurgy of the ancients.

      It may be remarked on the following lines of Virgil,

      … Alii taurinis follibus auras

      that bull’s leather is unfit for bellows, and that ox or cow leather only can be used for that purpose; but accuracy is not to be expected in a poet; and besides, Virgil is not the only author who employs the expression folles taurinos; for Plautus says also, “Quam folles taurini habent, cum liquescunt petræ, ferrum ubi fit.”

      In the oldest smelting-houses the bellows were worked by men. Refuse, therefore, and other remains of metal, are often found in places where until a recent period no works could be erected, on account of the want of water.

      Bellows made with leather, of which I have hitherto spoken, are attended with many inconveniences. They require careful management; are expensive in their repairs; and besides last often not more than six or seven years. If thin leather is employed, it suffers a great deal of the air to escape through it; an evil which must be guarded against by continually besmearing it with train-oil, or other fat substances; and this is even necessary when thick leather is used, to prevent it from cracking in the folds. Damage by fire and water must also be avoided; and every time they are repaired, the leather must be again softened with oil, which occasions a considerable loss of time.


Скачать книгу