Salt (47 page)

In 1925, Birdseye moved to Gloucester, Massachusetts, the leading New England cod-fishing port, and established a frozen seafood company. Birdseye’s invention came at a time when the demand for salted fish was in rapid decline in both the United States and Britain. The railroad, faster transportation, and better market systems had introduced more people to fresh fish. By 1910, only 1 percent of the fish landed in New England was cured with salt.

By 1928, 1 million pounds of food frozen in the Birdseye method was being sold in the United States. Most of it was being sold by Birdseye, who managed to find a buyer for his company just before the 1929 market crash. The company became General Foods, modeling the name after General Electric and General Motors, leaders in their respective industries. Birdseye once said, “I do not consider myself a remarkable person. I am just a guy with a very large bump of curiosity and a gambling instinct.” By the time he died at age sixty-nine, he had patented 250 inventions including dozens of devices and gadgets to improve the operation of his frozen-food process. He invented a lightbulb with a built-in reflector and a gooseneck lamp. But he will always be remembered for frozen food.

Fast freezing had at last made the unsalted fish people wanted, available to everyone, even far inland. Soon fishing vessels, instead of salting their catch at sea, were freezing it on board. Most salted foods became delicacies instead of necessities.

T
HE AGE OF
industrial engineering brought inventions to a salt industry that had been slow to develop new ideas. Most saltworks had been started as small operations by individualists who found original solutions to their technical problems. Some ideas, like the natural gas of Sichuan, had enduring and far-reaching applications. Some ideas, such as little paddle wheels with bells in the freshwater canals of Lorraine saltworks, to ensure by their tintinnabulation that the canals were not mixing with brine canals, were purely local. Still other ideas were based on cheap—often family—labor. One of the more curious examples of this was the
grau
, a sixteenth-century machine for lifting brine from storage tanks by means of a basket on one end of a lever. On the other end were ropes. Women would grab the ropes and swing off them like children at an amusement park, their weight hoisting the buckets on the other end.

Another example, using cheap labor, in this case slave labor, was a human-powered wheel used to pump brine. In medieval Salsomaggiore, men, chained at the neck, walked on the slats of huge wheels as on a treadmill. In Halle, brine was lifted on a wheel powered by twelve men. The man-wheel was used in Europe until the nineteenth century. In 1840, a twenty-eight-pond saltworks near Cape Ann, Massachusetts, supplemented the power from windmills on calm days by pumping brine by means of a fifteen-foot-in-diameter, five-foot-wide wheel with buckets on its outer rim. The wheel was powered by a large bull that walked inside the wheel.

Pumping brine was one of the most important engineering problems confronting salt makers, and it inspired many inventions. The first engine, the steam engine, which led the way to the Industrial Revolution, was invented in 1712 by an Englishman, Thomas Newcomen, and used exclusively for pumping water. The engine and its subsequent improvements were embraced by British and American salt makers, who had abundant fuel, mostly coal. In Germany, however, where there was not enough sunlight for solar evaporation and most of the springs had relatively weak brine, the cost of fuel was the central problem. In the seventeenth century, the Germans, learning that the salt at Salsomaggiore was more profitable than that in Germany, had sent investigators to Parma, convinced they would find new fuel-economizing technology. Instead they found that the Parmigianos simply charged a great deal more for their salt. For the Germans, steam engines consumed too much fuel.

S
ALT INSPIRED INNOVATIONS
in transportation, perhaps none more impressive than the canals of northern Germany, Cheshire, and the United States. The Anderton boat lift lowered entire loaded salt barges fifty feet from the Cheshire canal system down to the level of the River Weaver, which ran into the mouth of the Mersey across the bay from Liverpool. Built in 1875 to link the Trent and Mersey Canal to the River Weaver, it originally lowered the barges by a cantilevered hydraulic system based on counterweights and water power. But salt spills eventually turned the canal brackish and corroded the machine. In the twentieth century, an electric motor was added.

But it was in the technology of drilling, that salt producers had a momentous impact on the modern world. For a long time, the percussion drilling techniques of the Chinese were the leading invention. All percussion drilling, from early Sichuan to nineteenth-century Kanawha, essentially consisted of a chisel with a long shaft being whacked by a kind of hammer. In the sixteenth and seventeenth centuries, Europeans began using a rotary drill. They attached extension rods, known as boring rods, which, in 1640, enabled the Dutch to drill 216 feet under Amsterdam to reach a source of fresh water.

In the early nineteenth century, the drilling proved so successful at Kanawha that many Americans began deep-drilling projects in search of salt. An improved connection between the driving shaft and the drill shaft was developed in the United States; this connection was called a jar because it was designed to better withstand the jar of the pounding shaft. Europeans quickly adopted the American invention. Jars had actually been used centuries earlier by the Chinese, but westerners did not know this. At the time of the American invention of the jar, a western missionary, one Father Imbert, had gone to China to study the ancient wells of Sichuan. He reported on more than 1,000 ancient wells drilled to great depths and brine lifted in long bamboo buckets. He also observed that the Chinese had elaborate techniques for recovering broken drill shafts. In the West, such obstructions were often the cause of a well being abandoned.

I
N THE LATE
seventeenth century, when coal prospectors drilled into the Cheshire earth and found rock salt, it was the scientists, not the salt merchants, who were excited by the find. It demonstrated how improved drilling might someday open up an entirely new scientific field—geology, the study of the earth. Almost another century and a half would pass before England had its first systematic curriculum in the study of geology—established not by a geologist but by Humphry Davy.

Long before there were geologists, there were natural philosophers who contemplated the structure of the earth. Some of their best ideas remained unproved and unembraced. Nineteen hundred years before Columbus’s voyages, Aristotle wrote that the earth was round. An eleventh-century-
A.D.
Persian physician, Avicenna, author of some 100 works on medicine and philosophy, wrote about land being formed by prehistoric flooding, erosion, sediment deposits, and the metamorphosis of soft rock. He might have been remembered as the father of geology if more people had understood what he was talking about. But it would take centuries for the scientific world to catch up with him.

Throughout the Renaissance, new ideas were presented on the earth’s formation by thinkers in various fields, including Leonardo da Vinci, who opined that fossils were not, as widely supposed, placed in the rock by the devil but were formed by trapped plants and animals metamorphosing in the soil.

In the mid–sixteenth century, Georg Bauer, a German with the pen name Georgius Agricola, wrote on the origin of mountains, minerals, and underground water. His 1556 work
De re metallica
was the most complete work to date and for centuries to come on techniques for mining and producing metals and minerals, including salt.

Long before it was called geology, a number of geological debates persisted. One of them was on the origin of salt. Was a giant bed of salt at the bottom of the sea keeping ocean water salted? Or, as some believed, did the tremendous pressure at great depths so squeeze water that it turned salty? Another theory held that salt did not come from the ocean at all, but that salt on earth was carried to sea by rivers.

In the seventeenth century, René Descartes asserted that sweet water was soft and would evaporate, but salt particles were hard and would remain, and that was why the sea remained salty. According to his theory, the soft part of the ocean, the freshwater, was absorbed in the earth’s pores and then reappeared in the form of freshwater rivers, streams, and lakes. The earth not only had pores, but also had cracks, and these fissures were wide enough to let in the seawater, particles and all. This seawater usually formed brine springs. But some of these fissures were dead ends and did not lead to springs. The seawater that seeped into such places hardened into rock salt.

One eighteenth century theory held that the source of natural brine was that gypsum saturated with seawater leached salt. But another theory was that gypsum, a soft mineral common in most of the world, turned into salt. Water, according to this hypothesis, is salty in its natural state. The real question was: What caused freshwater not to be salty?

Robert Hooke, the seventeenth-century philosopher whose many scientific accomplishments include originating the word
cell
for the basic organism, concluded that salt came from the air. Others concluded that salt came from alkali, which turns out to be true, since alkali are bases. Some combined the two, concluding that salt was caused by the alkali in seawater mixing with the salt in the air.

The Germans tried to understand their many brine springs. Did brine come from rock salt below, as already appeared to be the case in Cheshire? Christian Keferstein, a Prussian lawyer, self-taught scientist, and author of a seven-volume geologic study, was convinced that the discovery of rock salt near a number of brine springs was coincidental. Rock salt, he believed, came from certain rocks.

In the eighteenth and nineteenth centuries, the raging geologic debate pitted neptunism against plutonism. The neptunists, led by German mineralogist Abraham Gottlob Werner, believed that the source of all bedrock was a common ancient sea. According to plutonism, most rock had hardened from a huge molten rock mass. Neptunism held that salt came from the sea, and plutonism insisted it was volcanic in origin.

In 1775, William Bowles used the salt mountain of Cardona to argue against the neptunism theory of salt. Logic indicated that such a huge mountain of solid rock was probably not left over from the ocean. Several others confirmed that this Pyrenees-sized mountain was solid salt or mostly salt—70 percent, one study contended—and that such a mass must have metamorphosized out of other rock. Eventually, neptunism was rejected, because both granite and basalt were proved to be of volcanic origin. But did that mean that plutonism was right about salt being formed by volcanos?