INSTRUMENTS
When Saladin looked at the sword of Richard the Lion-Hearted, he wondered that a blade so ordinary should have wrought such mighty deeds. The English King bared his arm and said: “It was not the sword that did these things; it was the arm of Richard.”
(1644)
INSTRUMENTS, IMPORTANCE OF GOOD
Dr. Z. F. Vaughn, well known in medical and scientific circles, has perfected a process for tempering to the hardness of steel the ductile metals, gold, silver and copper. Already Dr. Vaughn is manufacturing a large number of gold-bladed scalpels, probes, hypodermic and suture needles and other surgical instruments. These are replacing similar articles of steel.
The sharp edge of a gold blade is almost perfectly smooth; that of steel, no matter how fine the edge, is rough and saw-like. Because it is porous, the steel blade has never made a perfect surgical instrument. In the meshes of that metal may be hidden the infinitesimal germs of a virulent disease, or there may be a rust spot so tiny that it could not be discerned by the surgeon, but which might be sufficient seriously to poison the tissues in which the knife makes a wound, resulting in blood-poisoning that would cause death. In gold, being dense, this danger does not exist, and gold does not rust.
Besides, the gold blade divides evenly the flesh or tissue which it cuts; the steel blade really saws or tears its way through. Therefore, even when there is no infection, the wound made with a steel instrument does not heal nearly so readily as that made with gold. Another feature of a gold blade is that the wound which it makes leaves no scar.
(1645)
INSULATION
In 1846 Werner Siemens, of Berlin, discovered the non-conducting properties of gutta-percha. He coated several miles of copper wire with gutta-percha, and submerged it in the Rhine from Deutz to Cologne. Electric communication was thus established beneath the water from shore to shore. In 1850 a submarine cable was laid across the English Channel from Dover to Cape Grisnez. It consisted of a half-inch copper wire covered with nothing but gutta-percha, and loaded with lead to keep it down. The communication was perfect for a day, and then the wire refused to act. The electrical engineers were unable to explain the facts. At last the mystery was dissipated by a fisherman. A French fisherman set his trawl off Cape Grisnez. When he hauled it in, he picked up the submerged cable, from which he cut off a piece. This piece he carried in triumph to Bologne, where he exhibited it as a specimen of rare seaweed with its center filled with gold. The ignorant man had mistaken the copper wire for gold, but unwittingly he had served the electricians. They saw from the accident that it was not sufficient perfectly to insulate the cable, but that it must also be protected. In 1851 there was laid across the Channel a cable twenty-four miles long, consisting of four copper wires, insulated by gutta-percha, covered with tarred yarn, and protected by an outer covering of galvanized iron wires. That submarine cable proved a success, and ocean telegraphy became possible through an accident which compelled invention.—Youth’s Companion.