第1章
- Heroes of the Telegraph
- 佚名
- 946字
- 2016-03-02 16:28:23
THE ORIGIN OF THE TELEGRAPH.
The history of an invention, whether of science or art, may be compared to the growth of an organism such as a tree. The wind, or the random visit of a bee, unites the pollen in the flower, the green fruit forms and ripens to the perfect seed, which, on being planted in congenial soil, takes root and flourishes. Even so from the chance combination of two facts in the human mind, a crude idea springs, and after maturing into a feasible plan is put in practice under favourable conditions, and so develops. These processes are both subject to a thousand accidents which are inimical to their achievement. Especially is this the case when their object is to produce a novel species, or a new and great invention like the telegraph. It is then a question of raising, not one seedling, but many, and modifying these in the lapse of time.
Similarly the telegraph is not to be regarded as the work of any one mind, but of many, and during a long course of years. Because at length the final seedling is obtained, are we to overlook the antecedent varieties from which it was produced, and without which it could not have existed? Because one inventor at last succeeds in putting the telegraph in operation, are we to neglect his predecessors, whose attempts and failures were the steps by which he mounted to success?
All who have extended our knowledge of electricity, or devised a telegraph, and familiarised the public mind with the advantages of it, are deserving of our praise and gratitude, as well as he who has entered into their labours, and by genius and perseverance won the honours of being the first to introduce it.
Let us, therefore, trace in a rapid manner the history of the electric telegraph from the earliest times.
The sources of a river are lost in the clouds of the mountain, but it is usual to derive its waters from the lakes or springs which are its fountain-head. In the same way the origins of our knowledge of electricity and magnetism are lost in the mists of antiquity, but there are two facts which have come to be regarded as the starting-points of the science. It was known to the ancients at least 600 years before Christ, that a piece of amber when excited by rubbing would attract straws, and that a lump of lodestone had the property of drawing iron.
Both facts were probably ascertained by chance. Humboldt informs us that he saw an Indian child of the Orinoco rubbing the seed of a trailing plant to make it attract the wild cotton; and, perhaps, a prehistoric tribesman of the Baltic or the plains of Sicily found in the yellow stone he had polished the mysterious power of collecting dust. AGreek legend tells us that the lodestone was discovered by Magnes, a shepherd who found his crook attracted by the rock.
However this may be, we are told that Thales of Miletus attributed the attractive properties of the amber and the lodestone to a soul within them. The name Electricity is derived from ELEKTRON, the Greek for amber, and Magnetism from Magnes, the name of the shepherd, or, more likely, from the city of Magnesia, in Lydia, where the stone occurred.
These properties of amber and lodestone appear to have been widely known. The Persian name for amber is KAHRUBA, attractor of straws, and that for lodestone AHANG-RUBA attractor of iron. In the old Persian romance, THE LOVES OF MAJNOON AND LEILA, the lover sings--'She was as amber, and I but as straw:
She touched me, and I shall ever cling to her.'
The Chinese philosopher, Kuopho, who flourished in the fourth century, writes that, 'the attraction of a magnet for iron is like that of amber for the smallest grain of mustard seed. It is like a breath of wind which mysteriously penetrates through both, and communicates itself with the speed of an arrow.' [Lodestone was probably known in China before the Christian era.] Other electrical effects were also observed by the ancients. Classical writers, as Homer, Caesar, and Plutarch, speak of flames on the points of javelins and the tips of masts. They regarded them as manifestations of the Deity, as did the soldiers of the Mahdi lately in the Soudan. It is recorded of Servius Tullus, the sixth king of Rome, that his hair emitted sparks on being combed; and that sparks came from the body of Walimer, a Gothic chief, who lived in the year 415 A.D.
During the dark ages the mystical virtues of the lodestone drew more attention than those of the more precious amber, and interesting experiments were made with it. The Romans knew that it could attract iron at some distance through an intervening fence of wood, brass, or stone. One of their experiments was to float a needle on a piece of cork, and make it follow a lodestone held in the hand. This arrangement was perhaps copied from the compass of the Phoenician sailors, who buoyed a lodestone and observed it set towards the north. There is reason to believe that the magnet was employed by the priests of the Oracle in answering questions. We are told that the Emperor Valerius, while at Antioch in 370 A.D., was shown a floating needle which pointed to the letters of the alphabet when guided by the directive force of a lodestone. It was also believed that this effect might be produced although a stone wall intervened, so that a person outside a house or prison might convey intelligence to another inside.