National Geographic : 1988 Dec
communications via a modulated light beam. His concept was extended with development of fiber optics and lasers that eliminate the transmitting-medium obstructions and beam divergence in the air (and generate adequate beam intensity), which thwarted Aleck's initial efforts. In view of today's applications, perhaps Bell also enjoyed prophetic talent in rating the photophone as his greatest invention. T. KIRKWOOD COLLINS Salt Lake City, Utah Philipp Reis was never mentioned in the fasci nating Bell article. Even if he made his instru ment out of a beer-barrel bung and bratwurst, Reis named it the telephone, and Europeans are convinced, especially in the fairy-tale town of Gelnhausen, Hessen, that he invented it. His work was the leading reference in patent fights. MORGAN C. LARKIN Salem, Oregon Reis's instrument transmittedtones, not speech. The opening statement that "Everyone knows that Alexander Graham Bell invented the tele phone" exaggerates the meaning of everybody. It might more accurately read that Bell invented a telephone and was successful in the wake of great controversy and litigation in protecting his patent. I find merit in the minority opinion of Justice Bradley in the case of the People's Tele phone Company v. American Bell Telephone Company decided by the U. S. Supreme Court in 1888. The court was asked to invalidate Bell's patent on the grounds that the telephone was first invented by Daniel Drawbaugh of Eberlys Mill, Pennsylvania; this the Court refused to do. Jus tice Bradley wrote: "We are satisfied from a very great preponderance of evidence, that Draw baugh produced, and exhibited in his shop, as early as 1869, an electrical instrument by which he transmitted speech ... [He] invented the telephone without appreciating the importance and completeness of his invention. Bell subse quently projected it on the basis of scientific in ference, and took out a patent for it." FORREST S. SHEELY Salem, Indiana Not until 1880 did Drawbaugh claim in court to have invented the Bell telephone, the Edison transmitter, and other improvements. Asked to explain his experiments, he replied, "I don't remember." Letters should be addressed to Members Forum, National Geographic Magazine, Box 37448, Washington, D. C. 20013, and should include sender's address and telephone number. Not all letters can be used. Those that are will often be edited and excerpted. D Alarm clock insect world They may be the most mysterious of all insects. They certainly enjoy the longest life cycle. They are the periodical cicadas of the northeastern United States, and they ring in every 17 years. No one knows how their biological clock works, but we know it has been working with precision since the Pilgrims noted the insects, mistak ing them for locusts. Cicadas tunnel into the ground after hatching and stay there, sucking root fluids, for 17 years. Then they emerge by the millions in late May and early June. Shedding their skins and hardening into maturity, they climb into trees. The males "sing" an immensely noisy mating song by vibrating membranes on their abdomens. After mating, females deposit 400 to 600 eggs in slits in branches. In six to eight weeks the nymphs hatch, drop to the ground, tunnel under, and start the cycle all over again. Despite the cicadas' bulging red eyes and gaudy orange wings, birds, cats, and dogs gobble the defenseless insects. "They are not a health threat to humans," entomologist Gene Wood told the National Geographic News Ser vice, "so we might as well enjoy them while we can."