Andrea Kane is new to San Diego: the Navy has stationed her husband here, and they've landed in Imperial Beach. While he serves, she's become an aromatherapist and a perfumer. Locally, she's already making a name for herself by creating and marketing organic creams, lotions, and blends, pomades and balms. Kane and I are sitting side by side on a black vinyl couch in a coffee shop in Imperial Beach. I've found her because I need an expert to guide me into the world of olfaction, the odoriferous, the redolent, the aromatic. Kane is 34, wears a denim skirt, a silver-flecked black cotton shirt layered over a white T-shirt, and a fragrance. Whoa, what's that? I blurt, getting some creamy, warm waft from her hair. That hair is short braids, like sticks of cinnamon, that dangle on her forehead and flop when her raucous laugh jars them. "That," she giggles, "is me. That's my blend." She won't say what it's made of, only that she's working on it. "It's just a fragrance; it has no therapeutic benefits." Except, I think, to attract my notice of it as an enticing smell. I also detected, entering the cafÈ, a whiff of patchouli oil, an odor that, for me, signals strange. Kane says, yes, that's her too, a scent so strong that it tarries in the air several minutes after the person has passed.

In her mixes, Kane uses essential oils, distinctive volatile compounds produced by plants. A volatile compound carries a scent -- the plant's essence -- into the air. She says that "each aroma sets off a different physiological effect in the person who wears it or the person who smells it. For example, I have a new collection; it's all heart scents -- floral, rose, tuberose. When I put it on, I feel the effect -- calm, relaxed." New research on essential oils, she says, is showing that certain ones can reduce blood pressure and others can increase it.

Kane got into aromatherapy when her mother, a cancer patient, refused chemotherapy and relied on aromas to help endure the pain. "She lived with me the last month of her life and took no drugs at all. Instead, she took a mixture of cedarwood, frankincense, and sandalwood. I would rub it on her head, and she would inhale it." An essential oil applied on your body goes into your bloodstream, and you'll continue to inhale it, as will others. "She was in a tremendous amount of pain -- maybe the smell helped balance her and she moved to a different zone. The doctors were amazed." On difficult days, Kane makes "an aroma vessel," a necklace sachet that helps defuse her stress.

Personal fragrances emanate only around one's personal space. Public smells are something else. Their origins are legion -- from dump to church altar to ozone lingering after rain. I ask Kane, who's lived all over the world, what smells she remembers from other places. New York City, she says, is acrid from trash, urine, and feces, yet redolent of pasta, garlic, and Indian food. Hawaii wafts floral scents on warm, soft breezes. Some streets in Florence, Italy, smell of coffee, cigarettes, and Roberto Cavalli perfume. The Moulin Rouge in Paris is pungent with greasy food and sweaty body odors, a sensuous combination. Miami holds a spicy memory while San Francisco reeks of unwashed street people. The stink of the Big Apple was, at first, repulsive. But, Kane says, the nose adapts, and soon it's not too bad.

So what about Imperial Beach, I ask. What's its smell?

She smiles her way through some serious nasal pondering. Finally, she says, "Gray."

Gray?

"Gray and a bit grimy."

You realize, I say, that gray and grimy are not exactly smells. Grimy may contain the oily scent of mechanics working on cars in a closed garage. But gray, hey, that's not a smell.

"I know," she counters. "But that's it. Gray and a little grimy."

No sea? No salt? No seaweed? No fish?

"Nope. None of that. There's no other scent here. No floral. I don't smell trees. There are no trees. There's no homeless people. No outside smell. It just smells gray."

Later, walking down Seacoast Drive, I get a rush of spice from the aptly named Aroma Thai. But that smell isn't local; its pungency could be anywhere on the commercial planet. I don't expect all of San Diego to have a particular scent. But then I didn't expect Imperial Beach to be missing an odor either. What's a missing scent smell like? I walk farther down the boulevard, then sense Kane is right. It does smell gray, sort of flat, a bit winter woolen, damped down, maybe. I smell very little beach in this beach town.

On days when onshore breezes are strong, salt and seaweed smells remind us of how close to the ocean we are. But wind and proximity are everything. Most days, the cliffs near La Jolla Cove stink of cormorant and pelican poop, just as the Pine Hill Egg Ranch, east of Ramona, nauseates with the stench of bulldozer-mounded chicken manure. Odor's trinity is source, concentration, and dispersal, with the ripest smells coming from decaying organic matter. To get close to hometown olfaction, I need to hunt up the smells, their sources, and the noses who know them.

* * *

Our noses recognize and recall 10,000 different odors. Two scientists, Richard Axel and Linda Buck, who were awarded the Nobel Prize in Physiology or Medicine in 2004, have studied this encyclopedic acumen of the olfactory system. The nose, they found, is regulated by nearly 1000 different genes (about 3 percent of our total); what's more, smell may be the most heavily coded of the five senses. The nose's genetic abundance is, most scientists believe, a holdover from our animal past. Back when, our noses to the ground, we relied on smell for survival. Once we got off all fours, we traded smell and taste for sight and hearing. Sight and hearing are now primary to our beings. Our arts are visual and auditory, not olfactory and gustatory. Smell, as Helen Keller said, is the fallen angel.

How does our olfactory system work? First, there must be a source, say, an apple pie baking. The pie emits volatile scent molecules. We pick them up via receptors in our noses. About 50 million receptors crowd onto 2.5 square centimeters of the mucus-coated olfactory epithelium in each nostril. (Animal abilities to smell are astounding: the dog's olfactory epithelium, for instance, is 40 times larger than ours.) From the epithelium, electric signals travel to the olfactory bulb, which, like a relay station, disperses the signals to different brain regions. One region is the limbic system, the Grand Central Station of emotion and motivation, where emotions attach to smells. Say you smelled apple pie baking at your grandmother's when you were three. Today when you smell an apple pie baking, you might be transported to her kitchen. You may even associate the smell with your grandmother herself, a childhood memory of security and love, spiced by a single odor.

The science of smell is far more developed than the language we use to describe smells. Consider how many words there are for crayon colors but how difficult it is to name odors. Smell shelves a meager stock of nouns: odor, scent, aroma, fragrance, perfume, bouquet, stench, stink, fetor; and a few general adjectives: redolent, pungent, acrid, aromatic, perfumed, cloying, stinking, musty, frowzy, fruity, rancid, putrid, rank, foul, reeking, sweet, noisome. Since we have few precise descriptors for all 10,000 smells, we often identify them by origin. Hence, on a golf course we say, that's the smell of new-mown grass, or at an Arco station, that's the smell of gasoline. My elderly neighbor was a smoker and a widower who cooked for himself. Entering his home, I was repulsed by the smell -- fried chicken and cigarettes. No precise word for that caustic mix exists. Yet when I state the combination and you imagine a closed-up house, holding grease and Marlboros for years, everyone knows it's a stench.

Moreover, language gets closer to meaning via connotation. In our smell words, we note how some of them buddy up to taste -- fruity, rancid, sweet. Also, a metaphor can be animated by smell, I smell a rat, as can other figures of speech, such as He stank to high heaven. Or how about Juliet's calling Romeo's name from the balcony: What's in a name? That which we call a rose/ By any other name would smell as sweet. Language's adaptability to the figurative shows that the olfactory glossary is not impoverished.

* * *

One of the most powerful aromas comes from freshly ground coffee. Almost nothing negative arises with this smell. I think of a brew as early independence, when at college I discovered a coffeehouse with live folk music and poetry readings and I felt centered, free, myself. Lots of workers get a sharpened focus from their midafternoon java: Hey, this job's not so bad after all. There's the solitude and unhurriedness that a good book and a cup of coffee bring. We don't linger with food in our culture -- we stuff it in -- but we like to sip and nurse, smell our coffee mugs.

On the coffee farms of the world's temperate climates, the coffee bean is picked as a red berry, whose skin, after drying, falls away and exposes a green bean. Before they're bought, these beans go through a smelling-and-tasting process called "cupping." To learn how the nose is used in cupping and roasting coffee, I look up a buyer and a roaster at CaffÈ Calabria in North Park. Michelle Greisgraber is typical of most smell employees: she had no talent per se with nose or tongue (the two are linked in coffee sampling) that led her to this profession; rather, her skill was acquired through a demanding schedule -- two years as a coffee sampler who taste- and smell-tested eight hours a day.

Greisgraber, wide-eyed from daily cupping, is an attractive young woman who likes to pull, twist, and drape her long straight hair over her right shoulder. Before she buys any coffee, she tests, or cups, a sample: she's looking for defects that the green bean may have contracted between the time it was harvested and the time it arrived in the cafÈ. For example, she says "hidy" coffee has picked up "condensation in the bag and tastes like a sweaty, dirty horse." Coffee can start fermenting. Or it can become "baggy," tasting of the burlap bag it was shipped in.

Before we cup, Greisgraber takes a palmful of Sumatran and Colombian green beans, which have no smell (when it's picked, coffee smells like "sweet grass," she says); she roasts them in a small rotating barrel over a gas fire for eight minutes. At two-minute intervals, she describes the change from endothermic (taking on the heat, the first half of the roast) to exothermic (giving off the heat, the second half). During the first two-minute phase, the beans lose their moisture, brighten up, and smell like burning grass; in the second phase, they continue losing water and take on a "muffin" smell, which she calls "a bit irritating"; in the third phase, the beans crack, stretch, brown, and exude what Greisgraber calls "coffee's sweet odor"; in the fourth phase, the well-roasted, embrowned beans start to smoke, put out heat, and reach "that full coffee smell."

Greisgraber cups up to four times a day with four cups on the table each time, testing for taste, smell, consistency. The roasting done, she grinds the beans, spoons the grounds into shot glasses, covers them with 200-degree water, and lets them steep until they form a crust. The aroma is exotic. "Before the ground coffee is wet, it has a fragrance. Once it's wet, it has an aroma, and you can actually smell it off the steam." Sure enough, the wet coffee grounds smell richer than the ground coffee. To release the aroma, Greisgraber plunges a spoon through the crust and breathes in. It smells, she says, "sweet, chocolaty, full-bodied" -- all hallmarks of a good cup of joe. She smells the other glasses, checking for consistency. Next she scoops up a sample and slurps it "aggressively" into her mouth. She washes the coffee across her tongue -- "swish it around and chew it a little bit" -- and holds it several seconds before spitting it out.

I do as she does. The smell is sweet and chocolaty; the grains run over my tongue, tasting bitter (I'm a cream-and-sugar man), though the caramelized effect, the sugary bite of a just-roasted bean, is potent. The best part is the lingering; it sticks in my mouth that day and well into the wide-awake, work-filled evening. What does she like about our brew? "Low acidity, smooth body, long-lingering aftertaste that's sweet; it's a well-balanced and a well-roasted coffee." (A bad bean would produce coffee with no character. It would be "hollow," or absent of flavor. Worst would be to brew tainted coffee, although you'd smell its bagginess or hidiness in the roasting or grinding stages.)

Jesse Fox has been the master roaster at CaffÈ Calabria for nearly four years. Fox is dressed in black, wears rectangle glasses (2000's style), and sports sideburns that look like combs. One arm is covered with multicolored tattoos. He's quite animated, but not in a coffee-wired way. Rather, he's skin-wired, it seems, from plunging his hands into plastic-lined garbage cans full of roasted beans and cupping handfuls to his nose. "For the olfactory," he tells me, "I'd say the Colombian is our most aromatic coffee. As soon as the lid comes off, you can smell it. Coffee tends to get a little brighter three, four days after it's roasted."

Fox says that roasting breaks down "the surface tension on the bean. The oils come out, and the aroma comes out even more." We stand beside one of two giant batch dryers, or barrels, that turn and roast the coffee at an even 500 degrees. As in the sample roasting process, the beans change color from green to yellow to tan to darker tones (mahogany, chestnut) and, about two-thirds through the 16-minute roast, begin to pop. When the 20-pound lot is done, Fox tilts the barrel up and releases the beans -- a long sliding cheeeee -- into a cooling tray. This afternoon, he's just roasted a decaf blend. The tray's mechanical cooling arms stir the fresh-roasted coffee beans. Fox grabs a few, cracks one under his nose, and inhales. I crack a bean too, and we nod at each other: a nice aroma. It's not, of course, as potent as the odor from a freshly ground bean.

"At the end of the roast, those lipids and starches eventually turn into sugars, what we're trying to caramelize in the end. It produces that uniquely homogenized coffee smell." A coffee roasted about 12 minutes, an Italian roast, turns dark and oily; roasted to 15 minutes, it's a French roast, when the caramelized parts burn a bit and the bean is smoky flavored. Fox says that Starbucks is known for its "burnt taste," what he calls a "charred coffee. It has a smoky aroma, a smoky taste; there's no flavor, no varietal characteristic." He says that Starbucks and Peet's (known for its "syrupy" coffee that's twice-brewed) rush the process with their automated roasting systems. "If you force it, you end up not developing the coffee on the inside, on the molecular level. It's like putting a steak on a grill that's 500 degrees; you'll sear it on the outside, while the inside is still red."

Fox calls what he does at Calabria "an Old World operation. We use sight, smell, and sound as we go." During roasting, he pulls out a "tryer" from the barrel, a long sampling arm in which he can see and smell the beans' evolving constitution.

I have always thought of coffee as bitter; to roasters, it's sweet. Fox says the sweet is "not like milk chocolate but baker's cocoa, the unsweetened sort." The taste-aroma comes from the variety's locale, one that combines temperature and altitude: hot and moist Sumatra or the drier regions of Africa that produce lemony-tasting and puckery-smelling coffee. Fox hopes that the Calabria cup of joe possesses "flavor over robustness," which the many local restaurants that feature their blends also want. "We're going for that full city roast: more flavor, more body, more caffeine."

* * *

One recent afternoon I meet up with spice chef Don Robinson of Pacific Beach's San Diego Coffee, Tea and Spice Company. He lays out a dozen spice packs for us to smell. At 54, Robinson has a face from a Jimmy Cagney movie -- a boxer's face, a tad pressed-in, a tad roughed-up but angelically so. His nose, at least outwardly, seems worn from years of inhalation. He wants me to try his blend, Desert Blackberry Rub. Its main ingredient, roasted garlic, is blended with sea salt, basil, oregano, lemon oil, citric acid, hot chili powder from New Mexico, and blackberry extract. Robinson opens the Ziploc plastic bag, the size of a shirt pocket, then plunges his nose in and whiffs with fervor. He calls the blend "kind of tart, a mellow, garlicky flavor with herbs in the background. I'd sprinkle this on salmon or pork, and the flavor will permeate the fish as you cook it -- for an hour or so."

Robinson's Kona Supreme has coffee, rosemary, cocoa, orange, onion, minced garlic, and canola oil to blend the flavors. "It's got a great taste, and the smell" -- he cracks the pack open and inhales deeply -- "is a rosemary murky flavor with coffee and orange in the background." How did he create this blend? He walked into a restaurant in Seattle (a wolf in another wolf's lair), caught a whiff of a coffee seasoning, and started imagining his new concoction. "I've been thinking -- wondering -- about it for six months. I wanted to make a coffee-flavored seasoning, not to put in coffee, but for salmon or chicken. It's not really the taste of coffee; that sits off to the side. The coffee flavor helps accentuate the other spices. I know what the spices and flavors do when they integrate with each other." The different flavors, he says, taken together "create a new experience, as they tantalize different parts of your tongue."

In Robinson's blending room, he shows me his work space with a wave of his hand. I see boxes of spices stacked to the ceiling (the staples: granulated garlic, black pepper, seven kinds of paprika) and a table whose wood surface is lined with knife cuts. He says sales to restaurants and companies like food-distribution giant Sysco are booming; he hustles to keep up with orders, giving cooks "an edge. They're always looking for something different." He does three different barbecue sauces with "different notes" of celery, paprika, brown sugar, and salt. Sauces and blends should sit for 24 hours before they're used; then they can sit for two to three years, holding their flavor.

In the storeroom, Robinson unveils alphabetized boxes of "product," spices and blends, all with the San Diego Coffee, Tea and Spice logo, in 6-pound, 24-ounce, or 6-ounce plastic jars, each sealed shut. Robinson delightedly rips open one seal after another -- "How's this?" I sniff. "Isn't that nice," a statement more than a question. Anise; arrowroot; California bay leaf (6 ounces for $45, bought from Northern California; the drying process holds in volatile oils, and the leaves smell like a forest); granulated roasted garlic; Robinson's Italian Herb Blend (basil, thyme, savory, rosemary); lemon peel powder; and so on, over 50 spices and blends.

Robinson thinks in smell and taste. Cooking and blending for 30 years, he's had lots of practice. He imagines coffee and rosemary and garlic, their smells and tastes, the way a painter imagines colors and hues or a writer stories and words. It's best to think in terms of smell and taste, he says, for they're bound together. Our taste buds detect only sweet, sour, salty, bitter, or umami, the so-called savory effect. When a substance is in the mouth, its odor travels to the nose via the nasopharynx, a connecting passageway at the back of the throat. Once the brain processes the taste and smell, a flavor profile is created. This profile is what characterizes food before, during, and after it's eaten.

Although the ingredients are listed on his blend packs, Robinson guards the formulas. Chefs at the Poseidon and Donovan's, to whom he sells in bulk, have told him that his Kona Supreme is "incredibly good," especially on T-bone steaks. He says he can smell any spice blend, go to his kitchen, and reproduce it. "I can come real close." He's got a Mediterranean sea salt that, he says, he copied from a smell he detected at Point Loma Seafoods.

Robinson opens a packet of bay leaves that he cured and cracks a leaf between us. Later, he crushes some Mexican oregano (the Mexican variety goes on tacos; the Greek, on pizza) and spreads it liberally across his palm. He cups his hand and inhales the grass-green patch. Then he rubs it between his hands to release the aroma into the air. When I leave, we shake hands, and I smell that oregano and a hint of bay leaf for hours.

* * *

Where there's manure, there's stench. No one knows this better than brothers Dave and Rob, who run the Van Ommering Dairy, a 500-cow farm they inherited from their Dutch immigrant parents. But when I ask Dave, a lanky, convivial man who rushes about on his four-by-four, how he stands the noxious scent of fresh dung, which already has my nostrils flaring, he laughs and says, "What smell?" It used to be that dairy farmers who kept cows in corrals would shovel out the poop for compost or spread it on fields; or, when cows fed on grass, their hooves would work the manure into the ground, fertilizing the pasture. But all that's changed -- at least at the Van Ommerings'. The poop from their Holsteins is vacuumed up three times a day and fed into a manure digester. The digester produces methane gas, which is burned to supply the farm's electricity and heat, cutting their SDG&E bill in half.

The whole production is shown to me one recent bright morning, when glare and heat and the smell are particularly nagging. Usually, Dave says, there's a nice breeze coasting through El Monte Valley, dispersing or transporting the stink. Their Lakeside farm is a terraced assemblage of homes (where Dave's and Rob's families live), ponds, pens, stalls, a milking barn, outbuildings for feed and machinery, and new dwelling units where, after a day spent eating and being milked, the cows sleep 12 to 14 hours under misters and fans while lying comfortably on mounded waterbeds. On the top terrace sits the digester, a 30,000-gallon, 14-foot-deep concrete tank into which fresh manure is constantly cycled. The tank is covered by a canvas sail that billows up from the pressure of the gas.

Dave details the digester's process. Methane, an odorless gas, is a by-product of decaying organic matter. "Cow manure," he says, "has a higher potential for methane than, say, leaves or grass." As microbes digest organic matter, they produce methane and carbon dioxide. Both Dave and Rob say that they are used to the smell: they've adapted to it just as people in Los Angeles have adapted to pollution or the guy who works with chlorine all day seldom detects it.

Dave likens raw manure to "pudding." He says it's filtered of clumps and made very "liquidy." Over four days, the manure slowly crosses the digester's length and, as it goes, the gas "is sucked off." At the end, the remaining dark green slop dribbles over a weir, or dam, and collects in a third tank before it goes through a separator -- solids go one way, liquids another. The fluids are placed in a holding lagoon, where they're later used to irrigate the farm's fields of Sudan grass. The solids are dry, like a fluffy peat, with a barely discernible loamy scent -- the organic compounds in dirt, that lusty smell of earth, are gone. The peat is bought by farmers and gardeners.

In the morning, the cows walk through a pen and onto a wide, grooved sidewalk; there, each pushes her head through a stanchion to get to the feed. Dairy cows eat a high-protein, high-fiber, high-fat diet, "better than what humans" consume, Dave says. The diet increases the amount of milk the Van Ommering cows produce, some 3750 gallons every day. Feed odors are distinct: the corn smells like dry cardboard; the alfalfa hay is ambrosial; the mix of barley and mill run is sweet; the fiber-rich almond hulls are pithy; the protein-rich cottonseed is woolly. The cow's large nostrils detect, while their sticky tongues pull out, the sweetest parts of the feed. As they eat, they poop. Eat, poop, rest -- they are great efficient digesting and milk-producing machines.

Later, I ride the tractor with Garrett, Rob's teenage son. The tractor pulls a vacuum trailer that just fits the sidewalk, where the cows' feces have piled. On the trailer's undercarriage is a set of "wings" that scrape the manure and guide it to the vacuum. Needless to say, any stirring up of the waste makes the air reek.

With a full tank, Garrett aims its poop-shooter at the waste vat beside the digester. In the vat, the stench loosed by the splashing clumps is gag-inducing, at least to this city slicker. I pull back violently, while Garrett, in ball cap, long-sleeve shirt, long pants, and gloves, stands near the putrid pool and, when prompted, shouts that he "likes the smell." Having spent his 18 years on the farm, "It's like a reminder of the home atmosphere," he says. I inch closer, peer into the vat, and espy tiny bubbles, methane escaping to the surface. Earlier Dave had said that this concentration "smells awful, but that's actually good because it means the gas potential is very high." More stink, more gas, more savings. Suddenly, as if I still don't get it, a chunk of wet manure flies out of the vat and heads straight for my pant leg -- splotch.

* * *

The perfume industry's latest gambit is scent branding. It's part of what Leah Corradino of the W hotel on B Street -- a glitzy boutique hotel with pillow-piled couches, opaque linen curtains, and a video above the bar of a blue sky with scattered clouds rushing by -- calls a "multisensory experience" in accommodations. The marketing manager shows me a room that's just been "styled," the new word for "made up," by housekeeping. The room clicks to life when we walk in -- TV, music, and smell greet us. When the room's finished, the maid sprays a citron mist, which is subtle, a bit muted, but lasts. It smells "fresh," Corradino says. Does it have a name? "No, it doesn't have a name that we put out there for press and media. It's just part of the style department." It has no cleaning-agent smell: no odor of ammonia or vinegar. "It's not exclusive to the W," she says, "but I've never smelled it anywhere else. The idea is that with smell, it evokes a greater and deeper memory." Given a good stay, the scent will secure the memory. Given a lousy stay, the scent will secure that, too.

Smells are found in many Mission Valley businesses. At the Sony Style store in Fashion Valley, an electric diffuser, the ScentWave, streams out a spicy, citrusy blend. The Sheraton's lobby diffuser perfumes the room with a vanilla and lavender aroma, called the Sheraton Signature Scent. Next door at the Marvin K. Brown Cadillac dealer, longtime sales consultant Marsh Pilkington opens up a brand-new Escalade for a whiff of that new-car smell. "The smells in the vehicle are a blend of new leather and new wood, mahogany." Pilkington says it's that "brand-new leather smell, which is just like a new leather jacket." The Escalade, Cadillac's biggest seller, runs $66,000, with GPS navigation, OnStar security, heated and cooled cup holders. He says the new-car odor is not a big selling feature, though its presence is part of the "emotion" of the purchase. "People are enticed by it." Factory-fresh cars smell of volatile organic compounds: chemicals in adhesives, sealers, carpet, and vinyl that outgas into the air. A few studies contend that outgassing may be a respiratory hazard: in tests, dozens of volatile organic compounds have been found, among them, known carcinogens; however, quick degradation makes toxic levels hard to establish. Car washes sell a spray called Lane's New Car Scent, an odor mimicking expensive leather upholstery, luxury in a can.

In some Japanese companies, scent is used to stimulate worker efficiency. Through the controlled release of certain aromas, workers make fewer errors and report less fatigue. One study says that cinnamon and peppermint smells in cars lessen road rage. High-end candles scent the air of countless women's dress shops. A customer is not supposed to be able to describe the odor. The air should feel invigorated, not necessarily scented. In creating commercial environments -- lighting, music, spatial architecture -- a business risks faking its authenticity with a cloying odor and pissing off the customer.

* * *

On the eastern slopes of Mount Palomar is San Diego's wine country. A key to growing grapevines is well-drained soil, which, at around 3400 feet, the area has in abundance. The lack of rain is not a big concern: there's water 60 feet below ground here at the headwaters of the San Luis Rey River. A few vineyards, along Highway 79, northwest of Warner Springs, contour the hills of Sunshine Summit. One is Shadow Mountain Vineyards and Winery, the pride of Alex and Pam McGeary. They've owned the "family estate-style business" since 1990, when they bought the vineyard from a second-generation Italian family of vintners. Some of the vines -- dormant in winter (when they're pruned) and fast-growing from April bloom to September harvest -- are 63 years old.

With 20 acres of grapes, Shadow Mountain makes 1800 cases of wine per year. So says Alex, the viticulturist, an expert, as is his wife, at the tastes and smells of wine production before and after bottling. In late winter, Alex shows me the bare vines, which will soon flower and smell "wonderful." The scents follow the "ripening curve" of the growing season: grapes "need enough sugar in the vine to soften the seed and the skin. That's where you get aromatic expression during fermentation, because the sugar is fermenting into wine and carbon dioxide gas, the two by-products. Good fermentation and the development of alcohol draws out mineral characteristics of the skin, which also roll into aromatic expression."

Alex irrigates modestly during the winter; he adds small portions of fertilizer "so the energy goes into the cane and the leaf." In summer, he waters a bit more and manages the vine canopy to shield the grapes from sunburn, balancing photosynthesis and shade during the season's hot days. Watering and fertilizing too much or at the wrong time can make a fetid wine (as we'll smell in one of his vats). Alex takes me to the production pad, where grapes have been fermenting in large tanks since last fall. During the harvest, or crush, stems are removed from the picked grapes. In the tank, seeds and pulp are "fermented cold," at 40 degrees. "By cold fermentation I preserve aromatic and taste qualities, which is their freshness," he says.

First up is a batch of viognier, a white grape from southern France that Alex has grown at Shadow Mountain without fertilizer. At the bottom of the tank is a large spigot that he opens to fill our glasses; we twirl the wine, warming it up in the bowl-shaped glass and releasing its aroma. The first thing we smell is yeast and bentonite, a clay he has placed in the vat to attract particles and help clarify the wine. As the wine warms, the smell begins "to explode with aromatic qualities." What does he smell? "We're going to swim through a couple things. Beyond the yeast, I smell fruit. The fruit we're smelling is the viognier, a warm-climate variety." He spots alcohol, adhering to and dripping down the sides of the glass. He buries his nose in the goblet and breathes deeply. "It's releasing aroma with the more air we inject." Alex takes a quick taste, swirls it in the mouth, then spits it out. "It's tart but not overly tart. It's not grapefruit or citrusy. This wine is mildly aromatic. At this stage, I'm thinking, once it's filtered, it's not going to be a big rosebud in the nose. So I'm bringing in 5 percent chenin blanc to round it out and give it some depth."

This wine, he says, has a strong fruitiness (it "goes with shellfish"), but the flavor "is still hiding in there. It's like I'm searching for the taste on my palate, as if I'm going into a forest and going around every tree to hunt down the quality I want it to have." As his "work in progress" ages, Alex taste- and smell-tests regularly, making written and mental notes. At 60, he has a long palate memory, "built up through much repetition" of tasting the wines he's made. He wonders whether this "not-so-tropical" wine would benefit from oak chips, a fermentation seasoning he may add.

Our second batch is sauvignon blanc, a dry table wine. This one he's hoping to rescue. He bought the grapes from a vintner hobbyist whose wife wanted the vines in the yard for landscaping. Trouble was, the man had fertilized the plants throughout the growing season; when Alex crushed the grapes, "They smelled like shit." Now, when he opens the spigot, we both recoil a couple of inches. I get the odor of dirty laundry, while Alex says it's the smell of "sweaty leather." He continues. "This is like my problem child. If you get beyond all the garbage in the way, there are tropical qualities in this wine." We swirl, then taste. "The fermentation is clean; the flavor lingers on my palate and it's not displeasing. Everything foul about it is right in the front" of the tongue. "Get beyond that first tree in the forest. There's a long finish to this wine; it's not drying up. It's not bitter, sour, acidic. But it has a heaviness on the front side," which he hopes to tone down or, with enough babying, remove.

In the Shadow Mountain wine cellar, Pam joins us. She lays out seven of their bottles and a glass for me to evaluate smells and tastes; Pam and her sensing ability, learned and innate, will steer me. As she decants each wine, she compares the scent to fruits. She begins with the white, a 2005 viognier. "I get peach and apricot in this viognier," she says. "I get it slightly on the nose. Remember, with aromas in wine, we're talking subtle." We proceed: she compares while I smell and (can't help but) concur. Her palate savvy comes from years of discussing wine with enthusiasts at this counter. One comment may tell her that a person's palate is educated or abused. How does one abuse the palate? Smoking and hot pizza or soup burn the mouth, while too much jalapeÒo or horseradish could disable (temporarily) the nose.

One light red wine, a blend labeled "Old Gus Vineyard Rome-Style Red Table Wine," has "spicy, herbal characteristics; it's a little dryer and smells like dry basil." Sure enough, it does. Sipping on, I sample successively darker red wines; Pam provides their evocations: each wine will "have more nose." Sure enough. One has "a light raspberry characteristic." With another, a medium-body Syrah, the smell is "a lot more complex than the others, a multitude of smells and tastes. I'm getting boysenberry, blackberry, currants." Still another, a merlot, "is the big boy of flavor and aroma. When I pour, I can smell it from here. Very fruity. I get ripe bing cherries." Alex says it smells like molasses. A final dessert muscat wine, high in sugar and alcohol, smells like "pear, honeycomb, and a little fresh flower," Pam says.

And with that, I'm tipsy and agreeable and quizzical as to how the oak came out basil, how a grape smell crosses over to a currant cousin, how the hot summers of inland San Diego County ripen the flavors of red wine so that the foods they complement will taste better -- the mystery persists, though my unlettered nose is becoming more sensitive, more knowing, and, best of all, more carnal.

* * *

For four decades, first at Yale and, since 1994, at the Chemosensory Perception Lab at UCSD, Dr. William S. Cain has been testing and thinking about smell. He's in the autumn of his career; his gray-going-grayer hair and beard testify to age, while an office walled small by journals and binders says his interests remain active. Cain is a professor of surgery -- not a nose surgeon but a researcher and evaluator of what nose surgeons (otolaryngologists) fix when they operate. His lab's several grad students study people, not animals. They test responses to smell, occasionally working with the frustrated few who have smell disorders or have lost smell. Of all topics we discuss, Cain seems most engrossed by the link between memory and smell.

Cain's voice is brash and bottom-heavy, the room-filling presence of a radio DJ. His interests spring not from "any inherent olfactory ability," he says. His mother had a "good sense of smell," while his is "well educated. And if you think about it, it can get infinitely well educated. There's no end to the refinement or the abilities of people to smell; whether it's a spice chef or a scotch whiskey connoisseur. There's always another layer of sophistication you can achieve."

The chemosensory lab's website states that Cain and his colleagues study "how people perceive flavors," "how people discriminate, identify, and remember aromas and fragrances," and how people react to "indoor air pollution, sick building syndrome, and chemical sensitivity." In one of Cain's labs, an array of cones discharges randomized and very low concentrations of a scent from which a subject takes a two-second whiff. For their inhalation, people earn up to $100 a day.

Targeting workplaces and homes, the lab measures odors and particles commonly found in the air. "We live in an equilibrium with our environment," Cain says. "We have all these agents that play a role. A pertinent example. You come to see me for an evaluation. You have a headache and you've lost your sense of smell over the last six months. And yet it unpredictably comes back every few weeks, and then from nothing you can suddenly smell things. Then we get into your history; you may have allergies, which may set up a cycle that leads to true anosmia," or the loss of smell. "Allergens can cause changes in the upper airwaves that promote upper respiratory infections, from acute to chronic, and become chronic sinusitis, which you may battle all your life."

Cain sees a lot of patients who are devastated by losing smell. Trauma is often a cause: a blow to the head knocks out the nerve function between the olfactory bulb and the brain. What happens when a person is disabled from smelling? Unsafe vulnerabilities arise: you can't smell smoke, spoiled food, or the odor additive in gas. Without a telltale aroma, neither steak nor strawberries have appeal. People suffer embarrassment by losing their smell. Cain says he counseled a woman whose coworker complained one day about a rancid odor coming from near the woman's desk. The woman couldn't smell it. When he found the source -- vomit in a wastebasket -- she was ashamed; she hadn't known it was there. Another patient, a dog-washer who lost his smeller, said that without it he couldn't tell if the dog was clean.

"All things connected with motherhood," Cain says, "can stand the use of a good sense of smell," especially the scent of a baby's scalp. New mothers in his office break down at having lost the sense, even temporarily. Surgery may help, but it can't solve all cases. Between 6 and 15 million Americans have a smell disorder. And only 10 to 15 percent of those have been diagnosed: doctors are not educated enough about loss of smell. Patients end up in Cain's office as a last resort.

The link between smell and memory for Cain is complicated enough to need a story. In New Haven, where he taught environmental health at Yale, he would get cash from an ATM whose vestibule smelled like a room in Florida that he went to every year for a professional conference. The latter smell "had something to do with the salt air and the humid climate; it was a balmy Florida smell." Usually he presented a paper at the conference, so there was some expectation about addressing his peers. But the conference was always pleasurable: "I loved being in Florida and being at the conference with colleagues." He says that the first time he went to Florida, the stimulation of the conference and its attendant emotion may have gotten "processed" in terms of the Florida balm. But later in New Haven, every time he would open the door to the ATM, he would feel transported to Florida, "including the visual imagery." What was going on? Cain is not completely clear, but he believes it's two things: a chemical in the ATM vestibule that was also in the conference room in Florida (maybe a cleaning agent), and the brain's tying the two times and places together through emotion.

"It's a matter of interpretation," Cain says. "Yes, there's an agent in the two places. But more important there's a connection between the emotion and the imagery, which are both important parts of the story, so to speak." Cain calls smell a form of contextual learning, which happens on an unconscious level.

Could it be that when Cain entered the ATM vestibule, he triggered a rush of anticipation similar to his Florida experience? Maybe getting out $300 meant he was going shopping for something he wanted, a bit of expectancy he associated with the Florida hotel room?

In an e-mail, Cain says no. "What's important about odor-evoked memories is that there needs to be no reward or punishment when the odor brings back the past. So the $300 of your example is not necessary. The memory provides the original feeling, which was expectation but also anxiety. I never understood why I had a kind of pre-meeting anxiety in connection with the place where the meeting was going to be held."

More than 30 years ago I dallied with a woman in San Francisco. The moment I met her, I felt she was the strangest woman I had ever known: her living by astrological signs and wearing patchouli confirmed it. Today when I smell patchouli, my "odor memory" is, as Cain says, "not recalled but...triggered by re-smelling." The smell has a character, deeply familiar and exotic. In fact, anyone wearing patchouli oil in the range of my nose becomes strange (in a bad way too, because my dalliance with that woman ended in confusion). Another way to say this is, the smell of patchouli I always find to be strangely familiar.

The presence of smells, Cain insists, is "all about meaning, and meaning is all about context." Thus, smell and emotion must include time and place; they co-exist, reinforce each other, and, at times, link otherwise incomparable experiences. Cain says also that the retrieval of smells and their emotions is a form of intimacy, a way of endowing memory with an emotional immediacy to which the human brain is especially well attuned.

In a 1993 article, "Redolence Revealed," Cain elaborates on the idea why the system of olfaction makes us remember past occurrences, often what we thought was mundane or even unmemorable. A smell, he writes, "may reinstate the past like no other cue.... The personal singularity of such experiences typifies the intimacy between perceiver and odor. This intimate bond may lie at the heart of why unlearning seems rare. People faithfully remember odor quality and even odor intensity over very long periods. Moreover, first impressions rule: What people learned first they remember best."

It's no wonder that what we learn early and what is most familiar is comforting, secure. Perhaps this is nostalgia, the connection between the familiar now and the familiar past. I think back to Garrett Van Ommering, who said that he liked the smell of fresh cow dung. We might imagine Garrett going away to college for a semester and one day visiting a friend's dairy farm, walking by a cow pen, and taking a big lung-filling breath of animal, land, and waste. That lone breath tells him he's safe, he's comfortable, and he's almost home.