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The Limelight

Fall 1997 | Volume 13 |  Issue 2

POLITICIANS LOVE THE LIME -light, and so, it is said, do performers. But people familiar with the theater know that there is no limelight anymore, and there hasn’t been for ages. Most people don’t even know what limelight actually was.

What was it? According to one dictionary, limelight was: “1. An intense light produced by the incandescence of a stick or ball of lime (CaO: calcium oxide) in the flame of a combination of oxygen and hydrogen gasses, or oxygen and coal gas; called also calcium light, Drummond light . 2. That part of the stage upon which the limelight is cast, usually where the most important action is progressing. …”

IT SHONE on a lot more than actors

Why Drummond light? Lt. Thomas Drummond (1797-1840) was a member of the Royal Engineers performing a trigonometric survey of Great Britain in the early 1820s. During winters in London he attended lectures on chemistry by W. T. Brand and Michael Faraday at the Royal Institution. During one of these lectures he heard how lime became brilliantly luminous when heated to a high temperature. Drummond conjectured that such a light source could make distant surveying stations visible, especially at night and in murky weather. After some experimentation he was able to build a working model that used an alcohol flame and a stream of oxygen directed at a ball of lime.

In 1825 his calcium light, focused with a parabolic mirror, allowed him to take observations between Divis Mountain, near Belfast, and Slieve Snaght in Donegal, a distance of sixtysix miles. In other long-distance feats, as described by Knight’s American Mechanical Dictionary (1880), “the light produced by a ball of lime not larger than a boy’s marble, at Londonderry, was visible at Belfast, a distance of nearly seventy miles. Subsequently, Colonel [Thomas Frederick] Colby made a lime-light signal visible from Antrim, in Ireland, to Ben Lomond, in Scotland, a distance of ninety-five miles in a straight line.”

Drummond’s apparatus found an obvious application in lighthouses. Without the surveyor’s need for ruggedness and portability, a much hotter oxyhydrogen flame replaced the alcohol-oxygen combination, at Drummond’s suggestion. One observer at a test wrote that “there seems no great presumption in comparing its splendour to that of the sun.” By general consent the invention was dubbed the Drummond light.

Drummond was both modest and hardworking, two qualities that would make him universally esteemed as the administrator of Ireland when he was appointed to restore order to that troubled country in the 1830s. He never claimed to have invented the calcium light, insisting that he had gotten the idea from Sir Goldsworthy Gurney, a chemist who discovered the principle in the 1820s while experimenting with his oxyhydrogen blowpipe. Gurney, in turn, had learned about the intense, carbonfree heat of an oxygen-hydrogen flame from Dr. Robert Hare of Philadelphia, who had published a monograph on the subject in 1802.

ONE PROBLEM GURNEY had faced in building a practical lamp was that any sizable chunk of solid lime needs a large amount of heat to make it shine brightly, since only the surface emits light. To get around this problem, he experimented with powdered lime and even demonstrated a light made by, in the words of a contemporary writer, “directing a stream of oxy-hydrogen gas on a quantity of pounded egg shells.” In 1835 William H. Fox Talbot, who would later be known for inventing modern photography and deciphering the cuneiforms of Nineveh, obtained an even finer powder by soaking paper in a solution of a calcium salt and then burning it. Talbot’s powder could achieve incandescence with the flame from an ordinary spirit lamp. Work with such finely divided powders was aimed at small-scale applications, of course. For lighthouses and survey work, where a powerful, long-lasting light was needed, solid balls of lime were used.

As with many other technologies, war was a powerful stimulus to developing new uses for limelight. During the early years of the Civil War, the Confederates sent out large numbers of merchant ships and armed commerce raiders. But beginning in 1862, the Union Navy captured, one by one, the ports from which they sailed and blockaded the havens they had not yet taken. Many Union ships were equipped with Drummond lights, which helped them track down Rebels who tried to slip by under cover of darkness.

THE LIGHT PRODUCED BY A BALL OF lime not larger than a boy’s marble, at Londonderry, was visible at Belfast, a distance of nearly seventy miles.”

The two Confederate seaports that held out the longest were Wilmington, North Carolina, and Charleston, South Carolina. In the Union’s most serious effort to capture Charleston, in 1863, one early objective was to subdue Fort Wagner, an outpost defending the channels that led into the harbor. During the attack the Navy fired continuously into the fort for forty-two hours, day and night. As one historian puts it, “In the evening calcium lights cast an eerie glow over the area.” The light was intense enough to so blind Rebel gunners that they could not return the Union fire with any accuracy. Despite reducing Fort Wagner, and later Fort Sumter, to rubble, the Federals could go no farther into Charleston Harbor for fear of hitting floating mines, then known as “torpedoes.”

By the end of 1864, though the harbor remained in Rebel hands, Charleston was so tightly blockaded that only Wilmington offered the Confederates much chance of getting to sea, for it was defended by their most heavily armed bastion, Fort Fisher. On January 12, 1865, the largest Union fleet ever assembled—some sixty warships, armored rams, and monitors— approached Fort Fisher from the sea in an ultimately successful attempt to put it out of action.

But with this immense effort drawing almost every large Union vessel on the East Coast, several Confederate warships that had been trapped for months on the upper James River, near Richmond, Virginia, decided to try to move down the James. On January 23 the Rebel squadron embarked on its mission, hoping to attack Gen. Ulysses Grant’s base at City Point, below Richmond. At 7:00 P.M. the ironclads Virginia II (namesake of the ship better remembered today as the Merrimack ), Richmond , and Fredericksburg , along with four wooden gunboats and some small torpedo craft, started downriver.

The first gunboat went aground around eight-thirty. The Virginia II ran onto a sandbar, and soon the Richmond and two other vessels grounded. The Fredericksburg broke through the Union barricades, but it was recalled to stand guard over the Virginia II . Federal artillery on shore, by now well aware of what was going on, brought in a powerful Drummond light to illuminate the river. At dawn a shell hit the Drewry , a Confederate gunboat, and blew it up. By late morning, with the coming of high tide, the remaining ships, heavily damaged, had to withdraw.

They renewed the attack the next night, but the Virginia proved too badly hurt to persevere, and she dropped anchor. The attack was called off. John K. Mitchell, the Confederate flag officer, gave his reasons for abandoning the attempt: damage to the Virginia ; loss of gunboats and the Richmond ; loss of surprise; and the Union’s “powerful calcium light.”

After the war limelight found a variety of new uses. It illuminated the caissons in which workers dug the foundations of the Brooklyn Bridge in the 1870s and 1880s. The photographer Eadweard Muybridge, most famous for his animal-motion experiments, invented the zoopraxiscope, a device for showing photographs in rapid succession to produce a motion picture. The zoopraxiscope used limelight to project its images, as operators of “magic lanterns” had been doing for decades.

The term limelight took hold in the public mind, of course, not through engineering or warfare but through the stage. At the start of the nineteenth century, the only artificial light that theaters had available was the feeble glow cast by torches, candles, or oil lamps, sometimes intensified with reflectors. Although clever lighting designers achieved many striking effects with these few tools, including lightning flashes and burning buildings, they were often too weak.

Gaslight came into use in American and European theaters after 1815, but starting in the late 1830s, Drummond’s development outshone it. With mirrors and lenses, limelight’s fierce glow could be focused and projected—the first type of lighting able to be used in this way. In the beginning it was reserved for special effects, such as moonbeams, but in the mid-1850s it started to be employed for what twentieth-century thespians would call spotlighting. The dramatic impact of limelight increased after 1860, when electric ignition enabled gas-burning houselights to be turned on and off. Before this, theaters were rarely kept dark, since each light had to be reignited individually after the performance.

SOON, HOWEVER, ELECTRICITY superseded both gaslight and limelight. In the 1880s theaters began installing incandescent bulbs, which were easier to control and, more important, were much less of a fire hazard; some four hundred theaters had burned in gaslight’s first decade. Limelight, too, could cause fires—for example, when the gas apparatus exploded.

For applications requiring great intensity, the electric arc light began to replace the limelight in the 1880s as well. This apparatus, which used the strong glow created by electrical discharge across a gap between two carbon electrodes, had been tried as early as 1846, but the flicker and noise it created made it unpopular. These problems were soon reduced to manageable levels, however, and a full century has passed since the wonder of limelight was banished to the realm of metaphor, where it remains to this day.

We hope you enjoyed this essay.

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