In 1880, two French scientists, Pierre and Jacques Curie, found that pressure on the crystal would produce the electric charge, and that the charge was proportional to the amount of applied pressure. They named this phenomenon "piezo-electricity" (Greek: piezn to press). A year later, using both quartz and tourmaline, they proved the reverse: an electric charge changed the crystal shape. The Curies went on to design an instrument for measuring very small electrical charges by the amount of shape-change the charges caused in a crystal. The crystal they used was quartz, and the instrument became known as a piezoelectric quartz balance. The device was the subject of Jacques's doctoral dissertation in 1889.
In 1894, Pierre Curie met a twenty -seven-year-old Polish physicist who would use the balance to extraordinary effect. Her name was Marie Sklodowska, and a year later she and Pierre married and began the work that was to change the world. By late 1897 Pierre was teaching an electricity course at the Paris Municipal College of Physics and Chemistry. Two years earlier Wilhelm Roentgen had discovered x-rays, and a few weeks after that French research Henri Becquerel attended a meeting at the French Academy of Sciences and heard that the new rays caused phosphorescence on the glass wall of a vacuum tube. Since Becquerel's father had done research on phosphorescence, Becquerel began to investigate the possibility that the x-rays Roentgen had discovered might be caused by phosphorescent materials.
At one point in his experiments Becquerel used powdery white uranium salts: potassium uranyl disulfate. After wrapping a photographic plate in thick black paper to keep out the light, he laid a saucer on which some of the salts had been placed on top of the paper and then left everything exposed to sunlight for several hours. When he developed the photographic plate the outline of the salts was clearly visible, together with the outline of any object placed between the salts and the paper wrapping. Assuming the sunlight was causing the salts to fluoresce and generate the image, Becquerel prepared another experiment. For a number of cloudy days without sun the package (the wrapped plate, a copper cross and the salts) remained in a closed cupboard awaiting better weather. At one point Becquerel decided not to wait any longer and developed the photographic plate. To his surprise the cross was clearly visible in the picture even though there had been no exposure to sunlight. In May 1896, Becquerel announced the news and dropped the matter.
Nine months later Pierre and Marie Curie's quartz balance identified a small electrical charge in the air above the same uranium salts. Intrigued, Marie set out to discover if any other substances behaved the same way. On February 17, 1898, she tested a sample of pitchblende and discovered the charge it produced was much greater than that from the uranium salts. The curies began boiling down and distilling the pitchblende to find out what was causing the charge. By late June their highly concentrated sample was giving off a very large charge. The Curies described the substance as "400 times as active" as uranium, and in July, coined the term "radio-active". It was this radioactivity that had been causing the image on the photographic plate. In December 1898 they named their new substance "radium". One of the Curies' close friends (so close that after Pierre's death he would briefly become Marie's lover) was Paul Langevin, a brilliant physicist. Pierre had been Langevin's lab supervisor at the Municipal College and Langevin had been present at the start of the Curies' radioactivity work. In 1914, at the start of World War I, Langevin was working on ballistics when he was asked to look into the problem of submarine detection. Langevin turned to the old Curie quartz balance. In less than three years he produced what his lab team referred to as the "Langevin sandwich: two three-centimeter layers of steel sandwiching a four millimeter layer of quartz crystal.
When an electric charge of the right frequency was applied to the quartz it caused the crystal to change shape and eventually to oscillate at its own resonant frequency. This in turn caused the steel plate to vibrate. When the "sandwich" was set into the hull of a ship the vibrating steel would send out high-frequency pulses into the surrounding water. If these vibrations hit an object, they would bounce back and be picked up by a receiver, which would apply the returning vibrations to another quartz plate. The effect of these vibrations would cause the quartz to emit electrical signals that could be processed to show the range and size of the object. In 1918 the system identified a submarine from 600 meters away, even when the submarine was stationary on the seabed. British and American researchers took the technology (now known as sonar) to the same stage, then the war came to an end before ship-fitting could be begun, and in the 1920s all three powers dropped the matter. 
first broadcast station to be crystal controlled was WEAF in New Your City in
1926. Throughout the period of time
from 1926 to 1939 quartz crystal units were used by amateurs, broadcast
stations, and some manufacturers of two way radio communications equipment.
The crystals were all custom built and there still was no crystal
industry as such.
Efforts to develop a practical unit having a low frequency-temperature coefficient were successful in 1934 when the AT- and BT-cuts were discovered independently by Koga in Japan, by Bechmann and Straubel in Germany and by Lack, Willard and Fair in the United States.
One of the most important influences on the development of the crystal industry in the period 1935-40 was the Galvin Mfg. Co. (Motorola). Mr. Dan Noble, ex-professor of Electrical Engineering at the University of Connecticut, was convinced that crystal control was essential to effective two way radio communication. In order to obtain the crystal units which he needed for his new two-way systems he persuaded Mr. Galvin to place orders with and in some cases to subsidize a number of individuals who had some experience with crystal units.
The first reports of the growth of quartz crystals by Schafhäult in 1845 and by de Sénarmont in 1851 produced microscopic crystals. G. Spezia, from 1898 to 1908, published reports on the growth of macroscopic crystals. He used solutions of sodium silicate, natural crystals as seeds and supply, and a silver-lined vessel. By heating the supply end of his vessel to 320-350 °C, and the other end to 165-180 °C, he obtained about 15 mm of new growth over a 200 day period. Unlike modem practice, the hotter part of the vessel was at the top.
In the period before and during World War II, Richard Nacken led an extensive German effort to grow quartz crystals; especially once the supply of natural crystals from Brazil was blocked. They used an isothermal growth process that relied on the higher solubility of the vitreous silica supply to supersaturate the solution.
Following the war, researchers, working with the U.S. Army Signal Corps, studied the German work and developed it into a commercially viable process. C.B. Sawyer, D.R. Hale, Hans Jaffe and others at Brush Development, and then Sawyer Research Products, Inc., developed the low-pressure sodium carbonate process. R. Laudise, N.C. Lias, and others at Bell Laboratories and Western Electric developed the high-pressure sodium hydroxide process. Today, these processes are used world-wide.
The use of crystal control in military communications equipment did not become common until immediately prior to World War II. The armed services were in the process of converting to crystal control when the United States entered the war. In 1940 it was estimated that in the event of war, the armed services might require as many as 100,000 units. This seemed like a fantastic quantity at the time when all crystal units were made in a few small shops where a skilled worker might be able to make as many as 10 units a day. During the war, however, over 30 million quartz crystal units were produced through a crash program costing over one billion dollars. This project had a priority second only to the development of the atomic bomb. By 1943 about 130 manufacturers were engaged in the production of crystal units. Twenty three of these were in the Chicago area, 20 in the New York area, 15 in the Carlisle area and 14 in the Kansas City area
The task of coordinating the activities of 130 companies was was accomplished by the Galvin Mfg. Co. (later Motorola). Galvin Manufacturing was heavily engaged in the production of personnel radio equipment known as the "handie-talkie" and "walkie-talkie" sets, all of which used the FT-243 crystal unit. Mr. Elmer Wavering, Galvin Mfg. Co. undertook the task of expediting and scheduling the production of FT-243 units, testing and assembling them into kits each of which contained 44,000 units on 4400 different frequencies. Mr. Nick Anton, an assistant to Mr. Wavering, prepared and distributed a Crystal News Sheet which supplemented the grapevine and helped contractors to keep abreast of new developments and information related to the production of FT-243 units.
Important breakthroughs in quartz technology led to the development of x-ray
equipment which enabled the material to be cut at very precise angles.
Modern vacuum plating techniques also had their genesis in the war years.
 Burke, James , The Knowledge Web, Rockefeller Center 1230 Avenue of the Americas New York, NY 10020, Simon & Schuster, Copyright 1999 by London Writers, pp. 71-73
Copyright © 2001 thru 2013 by Theodore Lind