THE ARTIFICIAL AIR

Have you ever walked into a supermarket and headed straight for the bakery counter, enticed by the smell of freshly baked cake? If you have a logical mind, you may have wondered how the smell could be so strong when most of the cake was boxed or behind a glass counter. The reason: A synthetic "freshly baked cake" smell was sprayed in the air just to make your mouth water.

This sometimes happens even in a regular bakery, though you would not be as likely to suspect it there. Nowadays many bakeries are part of large chain-store operations. All the baking is done at only one of the stores; trucks carry the bread to the other member bakeries. When you next smell the aroma of bread baking, check to see if there are ovens anywhere on the premises. They may really be miles away.

Making the smell of baking bread causes many headaches in the laboratory. White bread, chemists complain, is one of the hardest odors to reproduce. Rye bread is much easier, because of the pungent smell of caraway seeds. Most people prefer the smell of white bread baking, nonetheless.

"I know of only three smells that are appetizing to practically everybody: baking bread, frying chicken and roasting coffee," says Victor di Giacomo, chief perfumer of Givaudan-Delawanna.

Modern packaging has not yet robbed us of the smell of frying chicken, but the other two might become victims of the times were it not for the chemist's art. Coffee that is vacuum packed in cans does not smell, but you may forget that fact when you sniff the air around it. Sometimes the odor of roasting coffee is sprayed on the outside of the grocery or supermarket. The absent-minded customer believes that coffee is being roasted inside the store.

The old-fashioned delicatessen or grocery store is slowly but surely being replaced by supermarkets, but its unforgettable smell will linger on. Chemists have devised a "pickle" perfume that can be sprayed on shelves holding jars of pickles. If you use your nose instead of your eyes you will think that you are in the old-style store, with its big, open barrels of pickles.

Even stores with bottled whisky do not always leave well enough alone. The owner of a large liquor store has given a laboratory the assignment of reproducing the smell of a certain brand of whisky. He wishes to spray his store with it.

Odors are not always sprayed into the air in order to get you to buy something; the motive sometimes is to bring you pleasure. The president of a large French perfume house was so carried away by his belief that perfume is essential to happiness that he climbed into an airplane and flew over Paris, spraying the city with gallons of the costly essence. There is no way of knowing how much happiness he brought into the lives of others. Personally, he got nothing but trouble. City officials objected, because he did not have a license. It is hard, though, to imagine just what license would cover spraying a city with perfume from an airplane.

The idea of improving the smells of subways, buses and streetcars appeals to anyone who travels any distance to school or to work. Can you imagine pushing your way onto a bus or subway train at 8:30 in the morning and taking a deep breath of sweet, fresh-smelling air? The French have tried to make this dream come true. Every station of the Paris subway, or metro, as it is called in French, was sprayed with perfume. The sprayers were on the last car of each subway train.

This principle could logically be carried a step further. Each car in a subway train or each bus can be sprayed. The cost is so high, however, that people just talk about it. Nobody does anything.

If you live in a city you have undoubtedly noticed that it is more unpleasant to be behind a bus than inside it. The strong-smelling exhaust fumes are thoroughly disagreeable. This problem can be solved. At least in Cleveland, you can be right behind a large bus without smelling the horrid odors. In that city a few drops of a chemical are added to each gallon of diesel fuel used by the buses.

When the engine heats up, this chemical is released into the exhaust. What kind of a smell is it? Violet and peach odors go into it, but the end result is fairly neutral.

The companies that make the deodorizing chemical think it will cut down air pollution, in addition to cutting down the bad smell. This has not been proven so far. The only evidence comes from the men who work in garages where the buses are kept. Those handling the untreated buses complain that their eyes keep watering. In the garages housing the deodorized buses there are fewer such complaints. But this may simply mean that without the smell the men are less aware of their discomfort. It is the same for the man on the street: The buses still give off exhaust fumes, but he does not mind them so much. The air he breathes seems to be fresh. He should stay away from exhaust fumes, nonetheless, as they contain deadly carbon-monoxide gas.

What does air smell like? Your answer to that would depend on whether you live in New York City, Los Angeles, Pittsburgh or the Maine woods. Today there are very few places where the air smells good. We like to think we have fresh air around us, but not many of us do - whether we live in cities, small towns or suburbs.

Is any one of the following near you? A paper mill? Petroleum refinery? Plastics manufacturing company? Synthetic rubber mill? A plant making textiles? Cannery? Fishery? Meat-packing plant? Chemical plant? Brewery? Even if you have answered No to all of these, there is surely a sewage-disposal plant or incinerator in your area. Just one Yes is enough to mean unpleasant odors in the air.

Luckily, for every bad smell there is a solution. Some industrial plants have equipment designed to keep gases out of the air; others depend on the skill of the chemist.

Not long ago people living in a small New Jersey town noticed that the air around them often smelled of dead fish. The odor, they soon learned, came from a factory that had just opened. Fish was being ground to make chicken feed. This knowledge was small comfort to anyone but the chickens. At last a large chemical firm was called in and asked to conquer that fish smell once and for all. A floral perfume strong enough to conceal this odor was developed, and engineers worked out a way of putting it into the plant's ventilating system.

Oil refineries produce some of the worst smells of all. The gases coming out of the smokestacks, called "stack gases," are very much like the odor of a mixture of rotten eggs and cabbages. In one Midwestern town people living near a refinery became so desperate that they went to court to force the oil company to shut down its worstsmelling operations. The company hurriedly called in the odor-control chemists. A smell-killing compound is now sprayed into the base of the stack.

You can take it as a fact that if you walk past a refinery and do not feel like burying your nose in a handkerchief some method of controlling the smells is being used.

Sewage-disposal plants, as you can imagine, produce perfectly horrible odors. To conquer these effectively it is necessary first to put a strong deodorant into the sewage water itself, and then to spray the air around the plant. Perfumes of an orange-lemon type appear to be the most successful.

Conquering bad odors must, like most things in life, be done in moderation. Mother Nature does know best, and terrible smells sometimes warn of danger. A rottenegg smell tells you that hydrogen sulfide is in the air around you, and you get away from it as fast as possible. This is a sound and healthy instinct. The gas will irritate your eyes and nose. If you breathe in too much of it you can become seriously ill. The smell-killing compounds that have been developed, therefore, are designed to stop working when the amount of gas in the air reaches a dangerous point. The odor of rotten eggs returns and everyone in the neighborhood departs.

Animal smells are not much of an improvement over industrial odors. If you had to work in an animal laboratory, a zoo or a circus menagerie, you might find it hard to keep on being kind to the beasts. The odors around the monkey, lion and tiger cages are particularly strong when nature is allowed to take its course. Nowadays it is often restrained. There is now a special "zoo" smell that can be blown through the cages by fans. Its manufacturer, Dodge & Olcott, reports that it contains eucalyptus, thyme, pine and camphor. A special formula has been developed to improve the air in animal laboratories and around them.

The air inside as well as outside a building can be made fragrant. The last word in smell conditioning took place one night a couple of years ago at a ball held in New York's Waldorf-Astoria Hotel. During the course of one evening $10,000 worth of rare French perfumes were sprayed into the air.

Somewhat less costly fragrances are sometimes added to the air-conditioning systems in modern hotels, public buildings, theatres and apartment house lobbies. In time, built-in smells may come to private homes as well. The scent is introduced into the blower system and comes out with the air. Light floral odors or mint types or citrus are most often used. Those who believe that variety is the spice of life use one odor for a few days and then shift to something else.

At the present time, spraying theatres and public buildings is still more customary than adding scent to air conditioning systems.

Department stores discovered a few years ago that spraying the air of the main floor with a well-known brand of perfume helped to sell not only that particular fragrance, but also everything else from socks to ice buckets. The pleasant smell puts people into a good mood. At holiday times scents connected with the occasion are often used. Next Christmas you might notice how many stores smell of pine and balsam, even if there is not a single pine branch to be found in any department.

Not all smells introduced artificially are pleasant. A patient at an extremely modern West Coast hospital complained recently that for all the bright chintz drapery and light green paint, the place still smelled like a hospital. Surely, air conditioning could keep the antiseptic aroma under control. It could, but it would make many patients uneasy. If they did not smell the familiar antiseptic and medicinal odors they would not think they were being cured. As a rule, when you smell camphor or eucalyptus you feel that a place has been made extremely clean. Some hospitals are gradually switching to floral perfumes, but it will probably take years for people to get used to the change.

Since the development of aerosols - the push-button spray cans - it is hard to find a home that does not have at least one deodorizer or reodorizer. Aerosols are the direct descendants of the old-fashioned spray gun. The cans contain perfume and a chemical, called a "propellant," which pushes or propels the fragrance out. You may be surprised to learn how little perfume is needed. The aerosol can is almost entirely filled with the propellant. Less than one quarter of one percent of the liquid in the can is perfume.

When these aerosols were first developed, they were used to kill bad smells only. After cooking cabbage, for example, the housewife would hurriedly reach for a deodorizer spray. In the last few years the principle has been carried further. Chemists have developed aerosols which can do several things at once. You can mothproof a closet and make it smell of cedar or pine besides. Insecticides have perfumes added, and so a playroom can be made sweet smelling as well as insectproof. There is now a room deodorizer designed to remove the odor of pets from the air, and replace it with the scent of your choosing. Does your linen closet have a section where you throw old rubbers, baseball bats and rock collections? A spray can take those odors away and add the scent of lavender or one of the "clean" smells specially designed to remind you of freshly laundered linens. Another simply removes smells, making the air completely odorless.

Aerosols can give each room in the house its own characteristic aroma. Kitchens can be sprayed with the scent of spice or mint. And who knows? An aggressive baking company might someday offer an aerosol of "freshly baked bread" smell to go with each packaged loaf. There is even a nursery odor, designed to smell the way people think a baby should. A girl's closet and dresser drawers can be sprayed with the cologne of the perfume she uses. A hostess could perfume her living room as well as her person before company comes.

Even your car does not need to smell of gasoline or the bananas your little brother mashed into the upholstery. Perfumed blocks can be placed in the glove compartment or under the seat.

Almost everywhere you go you are in for surprises planned by the enterprising smell-makers. A new world is right under your nose.

(From The artificial world around us, by Lucy Kavaler)