Fused Quartz

In the Lynn works of the General Electric Company, has been produced a substance known as a clear fused quartz, which possesses an astonishing catalog of uses and properties:

1.) It is the most transparent solid known, transmitting 92% of the light passed through a meter rod of it. The best optical glass transmits 65%; ordinary glass 35%.

2.) It transmits all the rays of the sunlight, including the ultraviolet and infrared, which are cut out by ordinary glass. Owing to this property it is expected to be of great value to medicine. By it diseased areas of the throat, nose, ears, stomach, hitherto inaccessible cavities, may be subjected to the action of these germicidal rays, as well as to heat. A sun-room made of fused quartz panes would have the same effect as sunlight in the open air. A quartz lamp will give a healthy sunburn.

3.) It is a perfect conductor of light. Light from a match or pocket flash at one end of a fused quartz rod 25 feet long passed through the tube without appreciable loss of illumination. Further, the light travels intact through bent and twisted tubes, around corners, no matter how long or devious the way, just as a hose carries water.

4.) It is a perfect heat transmitter, remaining cool on the surface while the heat rays pass through a tube of it undiminished.

5.) It has the lowest expansion ratio of any solid known. A tube of it one yard long, heated to 3,200 degrees Fahrenheit, increased but 1/50 inch in length. Platinum increases 1/3 inch when subjected to the same heat, and copper 3/5 inch. President S.W. Stratton, of M.I. T., former director of the Bureau of Standards, believes that all standards of length will now be made of fused quartz instead of platinum.

6.) It possesses extraordinary ductility and elasticity. A rod or tube of it, bent or twisted from its normal position, will return to its former shape when released, without setting permanently. It can be made to assume any desired shape.

7.) It is unaffected by sudden changes in temperature, can be welded without risk, and may be used for chemical beakers, thermometers, motion picture projection lenses or other apparatuses where glass is subject to intense heat, eliminating much costly breakage.

8.) It will be of very great importance in the manufacture of lenses for optical instruments, especially cinema, photographic, and astronomical. It may add materially to the efficiency of the best existing telescopes.

9.) It has extraordinary qualities of pitch, giving absolute and un- changeable standards. A tuning fork of it vibrates several minutes, giving out a note which does not change with temperature or other conditions. The fused quartz is manufactured from a fine quality of rock crystals from Brazil and Madagascar, but can be made in unlimited quantities in almost any part of the world. It can already be produced commercially at a fraction of the price of the fused quartz formerly made by hand, in minute quantities, at great expense. The quartz is made in specially constructed, vat-like, electric furnaces operating at times in a vacuum, and at other times under a pressure of 1,100 to 3,000 pounds of nitrogen to the square inch, or more than a million pounds on the top of the furnace. If the pressure were unloosed it would have the effect of a high-explosive bomb. The quartz is forced downward through the crucible' by a weight, and cut into tubes as it emerges. The product is to the eye a beautifully fine, clear, color- less substance.

The chief credit for the discovery goes to Edward R. Berry, Assistant Director of the Thomson Research Laboratory of the General Electric Company, who has worked at the problem for nearly ten years, in the face of great discouragements. He was constantly stimulated, however, by Elihu Thomson, the great engineer-founder of the Company (TIME, Feb. 25), who foresaw the modern developments of quartz research.

Scientists the world over are impressed by the potentialities of the quartz fusion process. Albert Einstein, interviewed in Berlin, was interested in its applications to his theory of the curvature of light, paid high tribute to the activity, courage, and idealism of American scientists.