In the year 1962 a marked advancement was made in developing a lamp that is not only efficient but also one that gives white light. This new lamp was an improved version of the mercury lamp, which yields light of a bluish nature. The inventor of that new lamp is Dr. Gilbert H. Reiling, now retired.

A brief description of the metal halide lamp is repeated here verbatim from an article in a GE publication that appeared in 1962³.

"The most efficient source of white light in the history of electric lamps was announced this February by Dr. Guy Suits, General Electric vice president and director of research.

"The new metallic-vapor lamp, because of its high efficiency and improved color, 'has the potential to revolutionize the lighting of streets, highways, industrial and other large indoor areas, stadiums, sports arenas, and shopping centers,' said Suits.

"In side-by-side demonstrations, the new developmental lamp was shown to be nearly five times as efficient as conventional incandescent lighting, and of comparable whiteness. Contrasted to standard mercury light sources, the new lamp has up to twice the efficiency and avoids the bluish color that has characterized lamps of this type in the past.

" 'One secret of the new lamp is the use of small amounts of metallic elements other than mercury, including sodium and thallium,' Suits said. He indicated, however, that details of the lamp's construction and ingredients would not be made public at the present time.

"Inventor of the lamp is Dr. Gilbert H. Reiling, who became interested in light sources while performing basic scientific studies of gas discharges as a physicist at the Research Laboratory. Contributing to the development are the laboratory's long-time programs in studies of arc temperatures, excitation and energy transfer mechanisms, and spectral characteristics.

"A number of unique new structural materials also have been incorporated in the new lamp, and operation under new and carefully controlled conditions of pressure and temperature also are credited with helping achieve what Suits called 'the best combination of efficiency and color in nearly a century of research aimed at improving electric lighting.'

"He explained that the new ingredients in the lamp serve to produce intense 'spectral lines' in that part of the spectrum which can be seen by the human eye, particularly in the orange and red regions. Efficiency is thus increased, since more of the electric energy is converted into visible light. Greater 'whiteness' is achieved because the additional spectral lines give a wider variety of visible colors than are produced in ordinary lamps of this type.

"The light produced by the new type of lamp can appear white if desired. It may also be designed to emphasize certain parts of the spectrum for special applications. Luminous efficiencies ranging from 70 to 110 lumens per watt are obtained, in contrast to a maximum of about 52 lumens per watt with mercury alone, and 56 with the addition of a phosphor to the bulb wall. Ordinary 100-watt incandescent lamps produce approximately 17 lumens per watt, although larger incandescent bulbs have somewhat higher efficiencies.

"The new metallic-vapor lamps are now being studied in a variety of forms and life tests are in progress. Additional research, development and life-testing will be required before introduction of a product can be considered..."

"THE PROOF OF THE PUDDING Improved efficiency and color control of the new metallic-vapor lamp described on page 8 is demonstrated in photo above. All three booths are illuminated with light of the same intensity. Signs on rear walls show the power inputs, indicating differences in efficiency of the light sources. At left, 800 watts of ordinary mercury lighting produces light of a characteristic bluish color. Booth at right is illuminated by standard incandescent lamps totaling 1900 watts. The new lamp (center booth) consumes only 400 watts of power to produce equivalent intensity and comparable whitness. (Note: Because of the physiological and psychological aspects of color viewing, and the technical limitations of color photography and printing, a photograph such as this represents only an approximation of the actucal effect of seeing the results 'live.' It is believed, however, that this illustration gives a fair representation of the observable improvement in whiteness and efficiency offered by the new metallic-vapor lamp.)"

The above picture and description are located on the inside back cover of the Spring 1962 issue of the General Electric Research Laboratory Bulletin³.

"Ingredients in the new lamp serve to produce intense spectral lines in that part of the spectrum that can be seen by the eye, particularly orange and red regions." (Reference 3, pg 8)

Mercury lamp on the left¹ and a metal halide (Multivapor^TM) lamp on the right (U.S. 3,234,421)

The new metal halide lamp, known within General Electric as the Multivapor^TM lamp, was introduced in New York at the World's Fair of 1965.

New lamp geometries have appeared since the metal halide was invented and some of those that were marketed in the first twenty years or so were reviewed by Dobrusskin in 1986⁶.

Relighting of the Statue of Liberty Much reconstruction of the Statue of Liberty in New York harbor took place during a couple of years prior to the Centennial Celebration in 1986. The Statue had much work done on it, including the lighting. Starting in 1984 a team consisting of Howard Brandston, a New York lighting designer, and a group from the General Electric Company, headed by Gilbert Reiling, designed the new lighting, which included metal halide lamps. A brief history of the Statue's lighting follows¹³:

1887 - (9) arc lamps in the torch, (5) arc lamps at the base
1916 - (246) 250-watt incandescent lamps located at the star points of the old Fort Wood and (15) 500-candlepower gas-filled incandescent lamps in the torch
1931 - Lighting replaced with (96) 100-watt incandescent lamps at the base. (13) 1000-watt and (1) 250-watt incandescent lamp in torch
1945 - (16) 400-watt mercury vapor lamps added
1949 - Torch lighting revised to (10) 1000-watt and (3) 200-watt incandescent lamps and (6) 400-watt mercury vapor lamps
1984 - A statue and torch lighting system using metal halide lamps was designed by Howard Brandston, a lighting designer, and a team from the General Electric Company, which included Gilbert Reiling. The new lighting consists of^*:

(40) 250-watt metal halide lamps on the statue body
(16) 250-watt tungsten-halogen incandescent lamps under the torch railing
(42) 6-volt spotlights illuminate the torch from below
(4) 1000-watt metal halide floodlights are mounted in the Statue's head

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* Although these lamps were listed as being in the new lighting¹³ it's not clear that the wattage value of the four metal halide floodlights is correct; the wattage should be lower. In addition, it is believed that half of the 16 halogen lamps listed above were replaced with 70-watt HPS lamps in reflectors.
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The lighting of 1916, mentioned above, was accomplished by H. Herbert Magdsick⁷, a General Electric Nela Park engineer, who was one of the first to employ incandescent lamp floodlighting.

For the 1986 project two lamps of different colors were designed and produced⁷.

The two pictures shown above were scanned from The Plain Dealer, Jul 4, 1986, pg 12B

On July 3, 1986 President Ronald Reagan was in attendance at the Centennial Celebration of the Statue of Liberty and he pressed a button to relight the Statue and later the Torch. The birthday of the Statue is actually October 28, 1886. On that day President Grover Cleveland was in office and he attended the ceremony.

Biographical Sketch of Dr. Gilbert H. Reiling Gil Reiling is a native of St. Paul, Minnesota, having been born September 19, 1928. He received a bachelor's degree from St. Thomas College in Minnesota, a Master's degree from the University of North Dakota and a Doctor of Philosophy degree in Physics from the University of Missouri in 1957. His future work activities were to be with the General Electric Company - first at their Research Laboratory in Schenectady, New York.

In an interview in 1996 the following was reported¹²:

"In 1959, Gilbert Reiling at General Electric's Schenectady Research Lab began working on the thermodynamics of the mercury discharge. By June 1960 he reported to lab management that he had made lamps with "twice the luminous output" of a standard 400 watt mercury-vapor lamp and "with a white color which appears more pleasing to the eye." His lamps contained various mixtures of sodium-iodide and thallium-iodide. GE began an intensive development program, and announced a commercial metal halide lamp in 1962."

In 1961 Reiling left the Research Laboratory. He spent his remaining working career with the General Electric Lighting Business Group at Nela Park in E. Cleveland, Ohio. At Nela Park he first became Manager of Advanced Product Engineering for the Photo Lamp Department. This position was followed by several appointments in the Large Lamp Department: Incandescent Engineering, Quality Control and Fluorescent Engineering. He became Manager of Large Lamp Engineering in 1971 and Manager of Engineering of the Incandescent Lamp Department in 1974. In 1980 Reiling became Manager of Advanced Lighting Applications and Industry Standards in the Lighting Technology Division. He retired about 1990.

Some United States and Canadian patents issued to Gilbert Reiling (in some cases as co-inventor)¹⁴:

1) US 2,976,451 - Electric Discharge Device - 1961/03/21
2) US 3,049,639 - High Power Switch Tube - 1962/08/14
3) CA 663,118 - High Power Switch Tube - 1963/05/14
4) US 3,234,421 - Metallic Halide Electric Discharge Lamp - 1966/02/08
5) US 3,236,269 - Photoflash Lamp Filling Machine - 1966/02/22
6) US 4,316,116 - Triple-Coil Incandescent Filament - 1982/02/16
7) US 4,361,782 - Jacketed Discharge Lamp Having Oxidizable Fail-Safe Switch - 1982/11/30
8) US 4,420,801 - Reflector Lamp - 1983/12/13
9) CA 1,172,682 - Reflector Lamp - 1984/08/14
10) CA 1,198,147 - Triple Coil Incandescent Filament - 1985/12/17
11) US 4,675,794 - Adjustable Mount For A High Intensity Lamp - 1987/06/23
12) US 4,678,960 - Metallic Halide Electric Discharge Lamps - 1987/07/07
13) US 4,723,097 - Rapid Restrike Metal Halide Lamp... Method Of Operating Such - 1988/02/02
14) CA 1,238,936 - Reflector Lamp And Lighting Systems ...For Architectural Lighting - 1988/07/05
15) US 4,808,876 - Metal Halide Lamp - 1989/02/28
16) US 4,853,597 - Rapid Restrike Metal Halide Lamp...Method Of Operating Such - 1989/08/01
17) CA 1,301,237 - Asymmetric Arc Chamber For A Discharge Lamp - 1992/05/19

Dr. Reiling has been a sought-after speaker and in the late 1980s he and his wife spent three weeks in China while he lectured, being part of the United States Illumination Engineering Delegation. He received the 1987 Manufacturer Medal and Purse, given under the terms of the James McGraw Award for Electrical People, and on February 9, 1992 he was inducted into the Hall of Fame for Science, Industry and Technology at the Ohio Center for Science and Industry in Columbus, Ohio.

Gilbert Reiling married Margaret A. Eckert on June 7, 1952. They have children Mary, Anne, Stephen, Vincent, Eileen, Louise, Gilbert and Margaret. Gilbert and Margaret Reiling reside in a rural area east of Cleveland⁸.

Note: The picture of Gilbert Reiling shown above was scanned from a website of the Smithsonian Institution¹². It is from S.I. Negative #99-4126, and is copyrighted by the General Electric Company.

Acknowledgement I am grateful to Dr. Gilbert H. Reiling for sharing some of his biographical information with me. He has always been an upbeat kind of person who contributed to science and engineering in many ways. His venture into management did not result in the termination of his interest and contributions to lamp development; this can be realized by looking at the dates of his patents. Because he had the requisite education in thermodynamics, and the required amount of determination, his metal halide lamp invention resulted in a white light source of extremely high efficacy - the upper limit of which has yet to be reached.

Thanks are also given to Janice L. Fraser and Jo S. Farnham, both at General Electric's Nela Park facility. Ms Farnham looked through back issues of the GE News for me and also provided photocopies of articles.

References and Bibliography 1) GE Lamp Bulletin, Large Lamp Department, Cleveland, Ohio 44112, January 1956, pp 41-49.
2) Gilbert H. Reiling, "Metallic Halide Electric Discharge Lamps", U. S. Patent No. 3,234,421, filed Jan 23, 1961, granted Feb 8, 1966.
3) "New Light Source", Research Laboratory Bulletin, General Electric Company, Schenectady, New York, Spring 1962, pg 8.
4) Gilbert H. Reiling, "Characteristics of Mercury Vapor-Metallic Iodide Arc Lamps", J. Opt. Soc. Am., Vol 54, pp 532-540, 1964.
5) The General Electric Story, 1876-1986, Hall of History Foundation, Schenectady, New York, 1981, pg 57.
6) Alexander Dobrusskin, "Review of Metal Halide Lamps", 4th International Symposium on the Science and Technology of Light Sources, University of Karlsruhe, F. R. Germany, April 7-10, 1986, pp 3-19.
7) "Lampmakers Glow in Statue Light", General Electric Lighting Business Group GE News, Jul 8, 1986.
8) "Gilbert H. Reiling", Who's Who in Technology, Vol 5 (Who's Who in Physics & Optics), North American Edition, 1986, pg 182.
9) Dr. Gilbert H. Reiling, Citation, Manufacturers Medal - 1987, The James H. McGraw Award.
(This is at least the second person from Nela Park to receive this award; in 1935 Dr. Matthew Luckiesh was also a recipient.)
10) A. Zachary Stein, "A Bright Idea - Munson Resident's Discovery Earns Place in Hall of Fame", Geauga Times Leader, Feb 3, 1992, pg A5.
11) Karen Sandstrom, "A Shining Light Gets Honored - Inventive Ohioan to Hold Spotlight at Hall of Fame", The Plain Dealer, Feb 8, 1992.
12) http://americanhistory.si.edu/lighting/bios/reiling.htm
13) http://www.endex.com/gf/buildings/liberty/libertyfacts/LibertyTorch.htm
14) http://ep.espacenet.com/search97cgi/s97_cgi.exe?Action=FormGen&Template=ep/en/advanced.hts
15) General Electric Lighting Business Group GE News, Feb 28, 1986, Mar 14, 1986, Mar 27, 1986, Jul 8, 1986, Nov 14, 1986.