A History of Inventions, Discoveries, and Origins (Vol. 1&2). Johann Beckmann

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СКАЧАТЬ for instance at Fairbairne in Belgium, and we believe the same has been adopted in some of our own manufactories to catch the floating particles, and thus to prevent their being drawn into the lungs during respiration. The reader may form some idea of the effective manner in which magnets can be applied, from the following incident which occurred to Prof. Faraday, whilst experimenting with a powerful (electro-) magnet; an iron candlestick which happened to be standing near its poles on the table at which he was at work flew to them, attracted with such violence as to displace or break everything in its way.

      In the 18th century, a new supposed magnetic power was discovered, and with various success has continued to be applied to the delusion of the public. About 1770, Father Hehl, a jesuit, the Professor of Astronomy at Vienna, who had great faith in the influence of the loadstone on human diseases, and had invented steel plates of a peculiar form, which he impregnated with magnetic virtues and applied to the cure of diseases, communicated his discoveries to Anton Mesmer, who subsequently invented animal magnetism or mesmerism. Mesmer made use of his friend Hehl’s plates to employ the magnet according to certain notions of his own. In his subsequent experiments magnets were gradually dispensed with, and as practised in modern times, they have been found unnecessary. Hence mesmerism or animal magnetism has no relation to the magnetism of the magnet, and may therefore form the subject of a future article.

      About the year 1798, a man named Perkins invented a method of treating various diseases with metallic bars called tractors; these were applied to and drawn over various parts of the body, and were supposed to cure numerous maladies, such as ulcers, head-aches, &c. These instruments were patented. A few years afterwards, Dr. Falconer had wooden tractors made so exactly to resemble those of Perkins, that they could not be distinguished by the eye; on employing these on a large scale at the Bath hospital, he found that exactly the same effects and cures were produced by one as the other. Since that time these tractors have hardly been heard of, and are now forgotten.

      Quite recently, a new means has been contrived in England for deluding the public, in the form of rings, which are to be worn upon the fingers or toes, and are said to prevent the occurrence of, and cure various diseases. They are called galvanic rings. But this invention may be with propriety classed with the real magnet, animal magnetism and tractation.

      What has been stated relative to the metallic tractors, equally applies to the magnetic rings; for although by the contact of the two metals of which they are composed an infinitesimally minute current of electricity, hence also of magnetism, is generated, still from the absurd manner in which the pieces of metal composing the ring are arranged, and which displays the most profound ignorance of the laws of electricity and magnetism, no trace of the minute current traverses the finger or toe on which the ring is worn; so that a wooden, any other ring, or none at all, would have exactly the same effect, as regards the magnetism or galvanism.]

      FOOTNOTES

93 In his Kollektaneen. Berlin, 1790, ii. p. 117.

94 Aëtii Op. 1. ii. c. 25.

95 In Stephani Artis Med. Princip. ii. p. 253.

96 De Lapidibus, lib. ii. p. 131.

97 J. J. Wecker, De Secretis.

98 I took the trouble to search for this passage in Jac. Hollerii lib. de morbis internis, Parisiis 1711, 4to, but I could not find it, though the beginning of the book treats expressly of head-aches.

99 Magia Naturalis, lib. vii.

100 Kircheri Magnes, sive De Arte Magnetica, lib. iii. c. i.

101 P. Borrelli, Hist. et Observ. Medico-physic. cent. 4. obs. 75.

102 Observations sur l’usage de l’aimant en médecine, par MM. Audry et Thouret.

      SECRET POISON.

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      Under this name are generally understood all poisons which can be administered imperceptibly, and which gradually shorten the life of man, like a lingering disease. They were not first discovered in the 17th century in France and Italy as many believe, but were known to the ancient Greeks and Romans, by whom they were used. I must however allow, that they were never prepared with more art at any period, or in any country, or employed oftener and with more success, than they were in these countries, and at that time. If it be true that they can be prepared in such a manner as to occasion death at a certain period previously determined, or that the person to whom they are given will die within a certain time limited, it must be confessed that the ancient poisoners have been far exceeded by the modern. But this advantage will be considered as scarcely possible, when one reflects upon the many variable circumstances which have an influence on the operation of medicines and poisons; and it has often happened that a company have swallowed the same poison, at the same time, and in the same quantity, some of whom have died sooner and some later, while some have survived. Thus died Pope Alexander VI. in the year 1503, and Cæsar Borgia recovered without any loss of health, though, by the bottles being changed through mistake, he drank of the poison that had been prepared for the other guests alone. At any rate, I am of opinion that the celebrated Tophania, when she engaged to free wives from disagreeable husbands within stated weeks and days, must have had certain and very accurate information respecting their constitution and manner of living, or, as the physicians say, their idiosyncrasy.

Some physicians have doubted respecting secret poison103; and others have only denied that its effects can with certainty be regulated to a fixed time104. I agree in opinion with the latter; but the former can be confuted by many examples both of ancient and modern times; for that the ancients were acquainted with this kind of poison, can be proved by the testimony of Plutarch, Quintilian, and other respectable authors. We are told by Plutarch, that a slow poison, which occasioned heat, a cough, spitting of blood, consumption, and a weakness of intellect, was administered to Aratus of Sicyon105; and Quintilian in his Declamations, speaks of this poison in such a manner as proves that it must then have been well known106. It cannot be said that such an invention was too great for that period, or that it required more knowledge of chemistry than any one possessed; for the Indians in America are acquainted with a most perfect poison of this kind, and can employ it with so much skill, that the person to whom it is given cannot guard against the treachery, even with the utmost precaution, but infallibly dies, though in a lingering manner, often after the expiration of some years107.

Theophrastus speaks of a poison which could be moderated in such a manner as to have effect in two or three months, or at the end of a year, or two years; and he remarks that the death, the more lingering it was, became the more miserable. This poison was prepared from СКАЧАТЬ