Absolute Zero and the Conquest of Cold by Tom Shachtman, Houghton Mifflin Company, $25, 261 pages. Reviewed in the Raleigh News & Observer on January 16, 2000.

The News & Observer


January 16, 2000

It's a cold, cold, cold world. Brrr!

By Phillip Manning

The surprising success of "Longitude," Dava Sobel's 1995 best seller about the scientific quest to build an accurate clock, changed the publishing world's view of the history of science. Now it is a hot topic. Short, easy-to-read books aimed at the public have replaced dense, theoretical tomes intended for scholars.

One reason for the genre's newfound success is that it offers a twofer - some history, some science. Richard Panek's "Seeing and Believing" (1998), for example, is a good read on the history of the telescope and the science of astronomy; Lisa Jardine's "Ingenious Pursuits" (1999) explores the roots of the scientific revolution in 17th-century Europe. Joining them is Tom Shachtman's "Absolute Zero and the Conquest of Cold." It is a subject that might appear trifling at first glance, but Shachtman shows that the artificial generation of cold is essential for modern civilization.

Without air conditioning, the South and Southwest would still be a scatter of sun-baked hamlets. (Imagine living in Raleigh or Phoenix without it.) With no refrigeration to keep foods fresh, megalopolises such as New York or Mexico City could not exist. And consider how inconvenient life would be without frozen foods - without fish sticks and Dove bars and pizzas in the freezer.

Shachtman, the author of 25 books, traces the history of mankind's search for cold from Nero, who invented the ice bucket to chill his wine, to a Harvard research team that produced ultracold temperatures less than a billionth of a degree above absolute zero. His tales of discovery and sketches of the scientists who worked on the problem of cold are engrossing. Unfortunately, he does not handle the science as smoothly. His explanation of the cooling methods used by the scientists in their quest for cold seemed perfunctory and sent me scrambling for my college texts to understand the chemistry. And near the end of the book, he completely loses the science thread that is supposed to stitch the stories together. Instead of a twofer, this book delivers only a one-and-a-halfer. Nevertheless, the fascinating history of cold makes it worthwhile reading.

Shachtman begins by explaining how the people of medieval Europe felt about cold. It "could neither be measured, nor described as other than the absence of heat. Cold was a mystery without an obvious source, a chill associated with death, inexplicable, too fearsome to investigate." Francis Bacon, England's first true scientist, was an early experimenter with cold. In 1626, he stuffed a dead chicken with snow to see if he could prevent it from spoiling. Bacon caught pneumonia romping around in the snow, but before he died, he said that his experiment to preserve the chicken's flesh "succeeded excellently well."

A century after Bacon's death, Daniel Fahrenheit invented a mercury thermometer with the scale we use today. With the advent of reliable thermometers, scientists raced to reach lower and lower temperatures. In 1823, Michael Faraday found that when a liquid evaporates, it absorbs heat from its environment and cools it. A rapidly expanding gas does the same thing. These discoveries led to the development of refrigerators and air conditioners, which use electric power to compress a gas and then allow it to expand and cool its surroundings. And only 70 years after Faraday's discovery, James Dewar used those techniques to liquefy hydrogen at minus 436 degrees Fahrenheit.

How low a temperature could one reach? The concept of absolute zero, which implies the absence of all heat, had been around since the 18th century. Because heat is a result of motion, absolute zero also implies the absence of all atomic motion. Since you can't get any more inert than complete motionlessness, absolute zero is a temperature below which you cannot go - and a state that can never be reached. This insight was formalized in 1905, when a German scientist, Walther Nernst, formulated a new thermodynamic law: Absolute zero, minus 459.69 degrees Fahrenheit, is unattainable.

The race to absolute zero could not be won, but the all-too-human passion for a chimera was not wasted. In 1911, Heike Onnes discovered that supercooled mercury offered no resistance to an electrical current, a phenomenon known as superconductivity. Today, superconducting wires are being installed at an electrical utility in Detroit. About 250 pounds of superconductor will replace 18,000 pounds of copper wiring, a substantial cost savings. Although superconductors are still in their infancy, Shachtman believes that industries based on them could rival air conditioning, artificial refrigeration, and even Dove bars as benefits of science's conquest of cold.