The story of early electric lighting is often dominated by incandescent carbon-filament bulbs and, later, by the emergence of fluorescent and neon technologies. Yet nestled within this evolution is the fascinating work of Daniel McFarlan Moore, an American electrical engineer whose innovations pushed lighting technology into new territory decades before mainstream adoption. His creation—known as Moore Tubes—represented one of the earliest forms of high-efficiency, gas-discharge lighting, offering brighter, cooler, and longer-lasting illumination than the incandescent lamps of the era.
Born in 1869 in Northumberland, Pennsylvania, Moore grew up in a period when electricity was rapidly reshaping American life. He attended Pennsylvania State University, studying electrical engineering at a time when the discipline was still in its infancy. His early career took him to the Edison Lamp Company, where he worked alongside some of the brightest minds in electrical science, including Edison himself.
While Moore respected Edison’s ingenuity, he quickly became dissatisfied with the performance of incandescent lamps. He found the light too yellow, too dim, and too inefficient—a technological limitation he believed could be overcome with a radical idea: instead of passing electricity through a heated filament, what if electrical energy excited a gas directly, causing the gas to emit light? This principle—electroluminescence via gas discharge—would later underpin neon signs, fluorescent lamps, and mercury-vapor technology.
Moore possessed a relentless curiosity and a deeply scientific mind. Beginning in the 1890s, he conducted late-night experiments in his workshop, filling long glass tubes with various gases and testing their luminescent properties under electrical discharge. His experiments required not only electrical expertise but considerable knowledge of chemistry, glasswork, and vacuum technology. Moore’s tireless tinkering eventually culminated in the invention of the Moore Tube—a long glass lamp that produced brilliant illumination by exciting purified gases with high voltage. Nitrogen-filled tubes emitted a warm, rose-white glow, while carbon-dioxide tubes produced a cooler, daylight-like white light. Both were markedly more efficient than incandescent lamps and generated much less heat, not to mention a significantly longer life.
The real technical challenge wasn’t producing the gas discharge—it was maintaining its stability. Gas-discharge lamps gradually lose pressure as gas molecules become absorbed into the glass or electrodes. Moore solved this problem by inventing an automatic pressure-regulating mechanism known as the “gas valve.” This valve contained a chemical compound that released small amounts of gas into the tube as needed, keeping the internal pressure consistent. With this innovation, Moore Tubes could maintain steady brightness for thousands of hours, far outperforming contemporary lighting technologies.
By the early 1900s, Moore had established the Moore Light Company, installing his tubes in prominent commercial spaces. One of the earliest and most celebrated installations was at the offices of the New York Times, where long runs of Moore Tubes illuminated workrooms with a clean, even light unmatched by incandescent bulbs. Department stores, factories, and office buildings soon followed, drawn to the brightness and efficiency of his system. Moore became known not only as an inventor but as a pioneer pushing lighting technology into a new scientific frontier.
Although technically brilliant, Moore faced significant business challenges. His system, while efficient, was expensive to install and required specialized maintenance. The tubes were large and fragile, and the high-voltage equipment made residential use impractical. By the 1910s, neon lighting—simpler in construction and easier to commercialize—was spreading rapidly, and Moore’s system began to fade from mainstream use.
In 1911, Moore joined General Electric, where he continued his research under far better-funded conditions. His insights directly influenced the development of early fluorescent lamps, giving him an important, though often underrecognized, place in the lineage of modern lighting technology. Moore continued working as an engineer and consultant until his death in 1936, leaving behind a legacy defined by brilliance, persistence, and visionary thinking.
Despite being overshadowed by larger corporations and later technologies, Daniel McFarlan Moore’s contributions remain foundational. Though they are largely forgotten today, Moore Tubes represent a critical step in the evolution of electric lighting. They demonstrated, for the first time on a commercial scale, that gas-discharge lighting could outperform incandescent technology in efficiency and longevity. Moore’s experiments paved the way not just for the neon signs that would electrify cityscapes, but for the fluorescent and high-intensity discharge lamps that lit the 20th century’s offices, factories, and roadways.
In retrospect, Daniel McFarlan Moore wasn’t merely trying to improve the lightbulb—he was reimagining what light itself could be.
Featured image courtesy of New York Neon Blog.
