Bài 1 · Mười chai và một cuốn sổ

Ten brown glass bottles, a stack of paper blotters, a pencil and an unruled notebook. That is the whole toolkit for the first lesson. Lê Mai's eight lesson blending course starts here, before any formula, by training the nose: teaching it to recognise and to name.

Ten bottles on the table

The professional perfumer's workbench has a name of its own: the perfumer's organ, a tiered desk holding hundreds of material bottles in an arc, like the keyboards of an organ. This lesson does not need that desk. Ten bottles are enough to begin, as long as the ten differ enough.

The nose learns through repetition and comparison. A smell met once is easily forgotten; the same smell met many times, beside other smells, with a written name, stays. So the most important tool on the table is not a bottle but the notebook. Every smelling is recorded: the oil, the date, the time, and a few words.

A blotter, or mouillette, is a strip of absorbent paper used to smell materials and to follow how a scent changes over time. The standard practice is to write the name and the dipping time at the top of the strip before dipping. Ten unlabelled blotters, after five minutes, are ten pieces of paper nobody can tell apart. All smelling happens on paper; nothing needs to go on skin.

Training the nose on blotters rather than at the neck of the bottle has a practical reason. The air in a bottle has built up and is far denser than the scent rising from a paper strip. A blotter gives every smelling the same conditions: the same paper, the same dipping depth, the same distance to the nose. When conditions match, the differences written in the notebook are differences of smell, not of method.

Choosing the first alphabet

A good set of ten bottles spans several fragrance families. The classification of the Société Française des Parfumeurs, set up in 1984, divides perfume into seven families: hespéridé or citrus, floral, fougère, chypre, boisé or woody, ambré or amber, and cuir or leather. Those fragrance families are a frame for choosing bottles: each bottle stands for a different region of the scent map.

A starting set might be: bergamot for citrus; peppermint, rosemary and lavender for aromatic leaves; geranium and ylang ylang for flowers; clove bud for spice; frankincense for resin; Virginian cedarwood and patchouli for wood and earth. Ten bottles, ten smells different enough not to be confused in the first week, and close enough in pairs to give work for the weeks after.

Each bottle in the set has a main molecule that is easy to read. Lavender is built on linalyl acetate and linalool. Rosemary is rich in 1,8-cineole and camphor. Peppermint has menthol and menthone. Geranium has citronellol and geraniol. Clove bud is almost all eugenol. Virginian cedarwood has cedrene and cedrol; patchouli has patchouli alcohol. Knowing a molecule's name is not yet smelling it, but it gives the nose something to hold.

There is a limit worth knowing. The largest constituent does not necessarily define the smell. The odour detection threshold, the lowest concentration at which half of a test panel notices an odour, differs by orders of magnitude between molecules. A compound at one percent can be more noticeable than one at fifty percent. That is why the alphabet is learned by nose, not by tables of figures.

Smelling in pairs to see difference

A smell on its own is hard to describe. Two smells side by side point to their own difference. Lavender and rosemary are both aromatic leaves, but with two blotters together, lavender reads round, sweet, slightly floral, and rosemary sharp, cool, with a camphor edge. Geranium and ylang ylang are both flowers, but one is green and rose like, the other dense, sweet and creamy.

The method is simple. Dip two blotters, one oil each, to the same depth, and label them with name and time. Following the library's blending basics, wait about five to ten minutes before judging, so the fastest part has passed. Smell the first, then the second, then the first again. Write down one likeness and one difference.

Other pairs follow the same logic. Virginian cedarwood and patchouli are both woody, but cedarwood is dry and pencil like while patchouli is damp, earthy and dark. Bergamot and peppermint both feel bright at first, but one is fruit peel and the other a crushed leaf. Each pair trains the nose to separate things it would otherwise group together.

Some materials are too dense when neat. Clove bud, ylang ylang and patchouli can overwhelm the nose straight from the blotter. Perfumers often dilute materials for smelling, at 10 percent or 1 percent in ethanol, since many only open up when diluted. An interesting pair for the second week is the same oil at two strengths: they are often two different smells.

Words for smell

Language for smell is poorer than language for colour. Most smell words are borrowed from other things: lemon, wood, earth after rain. Perfumery uses a fairly stable set of descriptors: citrus, green, herbaceous, camphoraceous, spicy, floral, powdery, resinous, woody, earthy, mossy, musky, sweet, dry. The library glossary has a section devoted to those words.

The shared vocabulary is a support, but the notebook also needs the writer's own words. A patchouli blotter might be written down as damp earth, dark wood, roots, or an old room. There is no wrong answer, only an inconsistent one. The aim is that next time, the same smell calls up the same words.

A good notebook page has four columns: the oil, the shared word, the personal word, and an object to compare with. Bergamot: citrus, green peel with a floral touch, like a freshly folded rind. Virginian cedarwood: woody, dry, like a pencil box. The last column is often the most useful, because a concrete object gives the next smelling a clearer point of comparison than an adjective.

A daily rhythm

The nose tires quickly. Smelling one odour continuously reduces the perception of it, a phenomenon called olfactory fatigue; a short break away from the odour lets it recover. So a practice session should be short. About fifteen to twenty minutes, three or four pairs of blotters, with breaks in between, gives clearer results than an hour of continuous smelling.

The smelling place also needs to be free of odour: no cooking nearby, no scented candles, no perfume on the sleeve. Used blotters go into a separate lidded box, by date, so their smell does not leak into the next session. Those blotters will be useful again in the second lesson, where time becomes the tool.

Practising at the same time of day makes notebook pages comparable. A few conditions go in the corner of the page: hot or cold, dry room or humid. After a few weeks, those small notes sometimes explain why a blotter smelled different although it came from the same bottle.

Some people cannot smell a particular compound even though their sense of smell is otherwise normal. This is called specific anosmia, and it is fairly common with some synthetic musks. If one blotter in the set of ten seems almost odourless to the person smelling, that is a valuable note, not a mistake. Why the nose tires and recovers is explained further in Ten Minutes Later, Gone.

The scent notebook after thirty days

Thirty days is a frame for record keeping, not a scientific threshold. After thirty short sessions, the notebook holds about a hundred blotter pages, enough to show how the nose has changed. The simplest test is blind smelling: someone else dips the blotters, with no name on the front, and the learner guesses. The result goes into the notebook like every other entry.

Comparing the first page with the last usually shows two things. The descriptions become more stable: the same oil is called by the same words. And the pairs that were once hard to separate, such as lavender and rosemary in the first week, become obvious. The pairs that remain hard are the task list for the next month.

The second lesson uses these same blotters but adds an axis: time. A blotter is smelled again after five minutes, one hour, one day and three days, and the ten bottles begin to sort themselves into top, heart and base. That lesson is Lesson 2 · One Blotter, Three Days.

Ten bottles teach nothing on their own.

The notebook is the teacher.

The nose remembers only what has been named.