In 1756 the Duke of Richelieu’s chef brought back from Port Mahon (a town in the Balearic Islands that the duke had conquered, in the military sense of the word) a recipe for a sauce based on olive oil and egg yolk. He called his discovery mahonnaise; later, it became mayonnaise. Of course, a story this specific about a preparation this famous is asking to be contested. Indeed, it is said, though less convincingly, that the word is derived from magnonaise (from magner or manier—to handle) or from moyeunaise (in the Middle Ages, the yolk of an egg was...

Bile is continually secreted by the liver and stored in the biliary vesicle, a little reservoir situated between the liver and the intestine, until the organism requires it for digestion. It is 90 percent water. The rest is a mix of bile salts, cholesterol, and lecithin (again!). In the 1960s, biophysicists Donald M. Small and Dikran Dervichian of the Pasteur Institute, in Paris, studied the behavior of bile as a function of its composition.¹ This led them to draw a triangular phase diagram as a practical way of representing the phases of a ternary (three-part) mixture for all the concentrations...

If you had been at the German university of Prague on March 14, 1888, and just happened to be peering over the shoulder of Austrian botanist Friedrich Reinitzer (1857–1927), you would have seen that he was writing to German physicist Otto Lehmann (1855–1922) at Aix-la-Chapelle:¹ Reinitzer proceeded to report the blue and violet color changes visible to the naked eye that he observed in chilling the substance to the point of crystallization. He described the behavior of cholesteryl benzoate crystals extracted from carrots and from gallstones. Now, suppose you were asked during a quiz: “What do a carrot and a...

Imagine a scene taking place two thousand years ago, perhaps more, against the backdrop of an Amazonian forest in Brazil. Its inhabitants, the Amerindians, tap the trunk of a Hevea tree, collect the juice—whitish, a little viscous—and drench their feet with it. Neither sap nor resin—fig trees and dandelions secrete a similar substance—the liquid in question is called latex. Its molecules are very long, flexible chains known as polymer, from the Greek polus (many) and meros (part). Each molecule results from the repetition of a smaller constituent molecule, or monomer (monos [single]), which hooks up chemically...

The height of the stream of water from a firefighter’s hose is limited by pressure and by water loss. It would be annoying were it to reach only to the seventh floor when the fire is raging above. However, if the firefighter adds a tenth of a gram of polymer per liter of water, the height will be increased by 50 percent and the risk of the stream breaking up will be minimized.

Polyoxyethylene, or polyox, is a polymer that has very long and flexible molecules and is soluble in water. The increased height of the jet results from the...

The stability of its foam is the trademark of a good champagne. It is due to the natural presence of amphiphilic molecules in the grape, amounting to just a few tens of milligrams per liter, positioned at the interface between liquid and gas. Most are proteins and polysaccharides. For crème chantilly and mousse au chocolat, the molecules involved are milk and egg white proteins, respectively. How can such a little quantity have such a big effect?

Freshly pressed grape juice—“must” in the parlance of wine making—goes through an initial fermentation in a ventilated vat. The result is a...

The stomach secretes foam as a result of excess acid; for a drug to get through, it must therefore be taken with an antifoam. Processing wastewater requires breaking down mountains of honeycombed films created by tons of detergent. During fermentation, the formation of bubbles is driven by air and promoted by microorganisms that produce surface-active proteins; this secondary effect may not be desirable. Antifoam industries also include oil, wood pulp for paper, sugar, water-based paints, and plant processing.

Both antifoamers and defoamers are made to be spread over a foam. It takes only the smallest amount of either. How do...

The lung is alveolar tissue covered with a film of liquid composed of 90 percent water and 10 percent mineral salts, phospholipids, and proteins. The alveolus, the functional unit of the lung, is a tiny elastic sac that permits oxygen to pass into the blood. Lungs are full of alveoli: three hundred million for an adult, or a surface that is between seventy and two hundred square meters for a tissue thickness of only a few micrometers. Breathing increases pulmonary volume by opening the thoracic cage and contracting the diaphragm, which increases the air-exchange surface area of the alveolar film...

Liquid has found another love interest! This time it is granular matter.

Solid grains suspended in liquid make ink. If they are borne by gas, the result is smoke. Liquid dispersed in gas is aerosol. Adding air to a liquid creates foam. Butter is a dispersion of water droplets in fat. Blood is a liquid—plasma—swimming with red and white cells and platelets. An emulsion is one liquid dispersed in another.

What connects all of these materials is that they contain finely divided matter. Whence colloid,¹ a substance made of particles “of colloidal size” in the solid, liquid, or...

“Don’t be deceived: My job is 3 percent investigation and 97 percent creativity. And if I asked myself why a recipe works, I would go crazy!” says Ferran Adrià, ushering us into his lair in Barcelona.¹ In the quest for sensitive matter, nothing beats getting into the kitchen when it comes to applying the concept to cooking. So naturally we decided to go see the most radical chef of our time, head of El Bulli, on the Costa Brava. “From April to October, each evening, sixty-five ‘actors’ gather at the restaurant for a mere fifty ‘spectators,’ ” he says wryly....

From the most majestic redwood to a unicellular bacterium, the cell is the smallest unit of living matter. No life is possible without it. The cell contains everything needed to survive in a perpetually changing environment. Although most cells are only a few micrometers in size, some, like neurons, can be as long as a meter. The cell is bounded by an extremely fine envelope that is seven to eight nanometers thick—the plasmic membrane. It encloses a solution, the cytoplasm, which contains thousands of different molecules. The membrane consists of a double layer of amphiphilic molecules, mostly phospholipids with...

No wonder people dream of making structures similar to that of the cell to use as soft capsules for transporting drugs through the blood for delivery at just the right time and place!

Whether by pill or by injection, drug therapy comes down to achieving both optimal action at a certain time after delivering the agent and subsequent subsidence. The cycle repeats with the next dose. However, the doctor wants the dose of the active molecule in the blood to remain below a critical threshold, at which there is a risk of drug-induced toxicity or intolerance, the formation of undesirable...

Granular matter merits a special stop on our itinerary, for its behavior is not determined at the molecular level but at that of objects visible to the naked eye—or nearly. The size of these grains—between a micrometer and a centimeter—makes the influence of thermal agitation negligible and any comparison with the behavior of molecules in fluid irrelevant. Yet sand flows between our fingers. Like a liquid, it takes the shape of its container, and, seemingly like a solid, it forms an immobile pile on a table. Landslides and avalanches attest to the double life of granular material—...

Having arrived at the duomo at the crack of dawn, I observe the preparations of the town’s minor patron saints for their annual outing: fifty-one impressive silver reliquary busts. Borne on the shoulders of parishioners from the neighboring communities and by young Neapolitans amid the cries, applause, and shower of flower petals tossed by people crowding into the streets and onto balconies, the saints will progress through the Via del Duomo, Via San Biagio dei Librai, Via Benedetto Croce, and finally enter the church of Santa Chiara. There, the city’s archbishop will give a mass, during which the faithful will...