The chief influence for the idea of the smell organ comes from imagined correspondences between musical notes and individual scents. The perfumer George William Septimius Piesse is often credited for making this relationship explicit. However, by the time Piesse published the first edition of his 1855 The Art of Perfumery, the idea of scented harmonies had already been in circulation in literary and medical texts for several decades.

In an 1838 novel the American lawyer and novelist Horace Binney Wallace had one of his characters, a gourmet named Mr Rolle, note that 'the objects which address the smell have never been reduced to a system'. Mr Rolle immediately adds that he had been 'engaged in investigating the matter aesthetically, and have nearly succeeded in constructing a gamut of odours, and I hope soon to present to my friends an overture of flowers' (Wallace 1838: I, 107-8). Mr Rolle described one use for the smell organ that would recur in later texts: to produce a concert of broadly pleasant – in this case floral – scents. The same idea of was imagined by William Sloane Kennedy when he named an imagined smell organ the ‘florichord’ (Kennedy 1897: 15). The medical literature was slightly more neutral and noncommittal in how smell harmonies might be used in practice, preferring to simply suggest that they might be possible. In the 1840s the physiologist and comparative anatomist Johannes Müller argued that there was 'no exact proof that a relation of harmony and disharmony exists between odours as between colours and sounds; though it is probable that such is the case, since it certainly is with regard to the sense of taste' (Müller 1842: II, 1317). 

In 1855, when Piesse first published his ideas on smell and odours, he briefly described his core idea in an entry on a sweet-pea scent:

There is, as it were, an octave of odours like an octave in music; certain odours coincide, like they keys of an instrument. Such as almond, heliotrope, vanilla, and orange blossom blend together, each producing different degrees of a nearly similar impression. Again, we have citron, lemon, orange peel, and bernea, forming a higher octave of smells, which blend in a similar manner. The metaphor is completed by what we are pleased to call semi-odours, such as rose and rose-geranium for the half note; petty grain, neroli a black key, followed by fleur d'orange (Piesse 1855: 63).

This idea, which clearly captured the imagination of readers and reviewers, was built on in subsequent editions of Piesse’s book. In the 1856 edition of his book Piesse quoted a favourable review of the first edition, in which it had been agreed that there was nothing 'contrary to sound reason in the idea, that the whole of the pleasures of the sense of smell will be found to depend upon cognate laws' (Piesse, 1856: 108). The use of the term ‘laws’ indicates one context for the writing and reception of the book: the rise of psychophysical ideas about the senses in which sensation and sensitivity could be measured according to a series of laws (Tullett 2023).

By the time of the 1862 edition of his book Piesse had taken the short passage on octaves and harmonies from the first edition and expanded it into a concept that he returned to throughout his text. This also included the, now famous, illustration of the ‘Gamut of Odours’. This included two sheet-music diagrams illustrating the ‘Treble, or G Clef’ running from ‘F Civet’ to ‘D Violet’ and the ‘Bass, or F Clef’ running from ‘C Rose’ to ‘C Patchouly’ [sic]. The perfumer, Piesse instructed, should look at these diagrams and then 'take such odours as chord together' to ensure that 'the perfume will then be harmonious'. The illustrations of the gamut were therefore followed by ‘bouquets of chords’ produced according to the ‘laws of harmony’ (Piesse 1862: 27-30).

Many literary texts and visual satires took forward the idea of the gamut of odours and imagined smell organs or machines on which scent could be played to audiences. George William Septimus Piesse' son, Charles Piesse, published a work on smell in 1887. In that work he gave the gamut of odors, which he describes as containing 'some fifty odours', the name 'odophone' (Piesse 1887: 97-8). In his adventure novel Kaloolah the American author William Starbuck Mayo described a performance on a ‘perfume machine’ by an African prince, that used ‘more than fifty distinct perfumes’ (Mayo 1887: 340). The use of the same number makes it likely that Mayo took his inspiration from Piesse junior’s discussion of his father’s gamut of odours.

In these examples the sometimes the scents stick within the fragrance parameters imagined by Piesse. However, in other examples performances included more troubling and potentially offensive odours as well. In Kurd Lasswitz’s novel, set in the year 2371, the key protagonist named Aromasia is an expert player of a new musical instrument known as an ‘Ododion’. Aromasia’s own version of this ‘odor piano’ was of German make and was

… celebrated for the great compass of its odours, commencing in its lowest keys with the musty odour that permeates a cellar and the mouldering smell of a sepulchre, and reaching up to the exceedingly fine perfume discovered in the year 2369 and called "essence of onion" (Lasswitz 1879: 5).

In the first actual use of a ‘smell organ’ in public performance around 1900, a series of scents were covered that ranged from tar, ozone, and millefleurs; through magnolia, incense, and the smell of horses; to broiled sardines, flaming torches, and gunpowder ('A Concert in Perfumes', 1900: 876). In Mayo’s imagined perfume-machine there 50 or more perfumes were accompanied by ‘fundamental and controlling odors, by which the whole scale can be modified at pleasure. The three principles of these are garlic, musk, and sulphurated hydrogen’ (Mayo 1887: 340). Whilst the initial gamut of odours was developed for the use of fragrance composition, it is clear that those who imagined smell-instruments were thinking in far more varied olfactory terms.

The idea of the perfume organ came from – and physically existed in – several different locations. Perhaps the first of these was the chemical laboratory. In the early nineteenth century the industrial chemist was an increasingly important figure in a range of settings. From 1838 to 1839 the Scotsman George Wilson served as laboratory assistant to Dr Thomas Graham, lecturer in chemistry at University College London. George William Septimius Piesse, of gamut of odours fame, also studied chemistry under Dr Graham at University College London only a few years later (Anon 1883: 255). In 1856 – only a year after Piesse first discussed the idea of smell octaves and harmonies, Wilson published a book on the senses, titled The Five Gateways of Knowledge, in which he explicitly mentioned the idea of a smell organ. Wilson asked his readers to:

visit a scientific chemist's laboratory, and examine his specimens one by one, and they will easily satisfy themselves that a fac-simile of the largest church organ might be readily constructed, in which each organ-pipe, sounding a different note, should be represented by a phial exhaling when opened a different odour (Wilson 1855: 61).

Perhaps it was the experience of Dr Graham’s laboratory at University College London that also prompted Piesse to imagine a gamut of odours. Certainly, the images we have of eighteenth and nineteenth-century chemical laboratories demonstrate how easy it would be to imagine a scent organ based on the layout of the containers and experimental implements. In these images shelves filled with glass phials, bottles, and other containers attached to walls or desks hang over the benches at which chemists work, like the pipes of organs sitting above the keyboard and pedals of an organ. When one compares the visualisations of smell-organs – such as the 1922 image accompanying Joseph H. Kraus’ piece in the journal Science and Invention – the similarity between the chemical laboratory desk and the scent organ becomes clear (Kraus 1922).

When Lasswitz imagined the development of a smell piano he thought that it would first be 'exhibited as a curiosity only in all the cities of the world' but that it would soon find 'its way into the houses of private families' whose children would be encouraged practice the ododion 'to the great annoyance of some of their neighbours' (Lasswitz 1879: 6). As it turns out, Lasswitz was partly right in predicting the peripatetic existence that the smell-instrument might take on.

In 1900, two years before Sadakichi Hartmann debuted his own perfume concert in New York, we find the first example of a smell organ being put into practice. Mrs Rita Piselli, poet and performer, developed what she termed the ‘rhinotic art’ of scent performances that were often accompanied by poetry. A later account in 1938 recalled that the concerts

took place around 1900 with lively success throughout Italy. These were evenings in which the speaker Rita Piselli aided by her husband, Mr. Ernesto, concerted her prose and poetry with odours corresponding to the images of her saying. If she spoke of port workers, behold, a strong odour of tar would emanate from the hall, while poetizing on Sicily, the audience would be hit with a pervasive odour of orange trees, and so on. The machine that emanated all this was, according to a chronicler of the time, 'much like the church organ.' The Pisellis always kept secret the way in which it worked… after brief explanations on the rhinotic art, the concert began with the lights off. The audience, skeptical at first, always ended up warmly applauding the performance (Belli 1939: 154).

Whilst it has been difficult to locate further contemporary descriptions of the Piselli’s performances in Italy, we do have some information one other performance: at the Paris exposition in 1900. This gives us a bit more detail on how the instrument was constructed and played:

As to the instrument producing the various perfumes, it is on the order of an organ, is played by finger keys and pedals, and consists of a large number of pipes, at the ends of which the perfumery reservoirs are located. The smells are released as soon as the keys are pressed down, whereby a valve opens, supplying the necessary wind ('A Concert in Perfumes', 1900: 876).

The precise relationship between keys on the organ or piano, the pedals, and the scents thus produced is not clear in all the cases of imagined instruments. In a 1922 piece in Science and Invention, however, the American writer Joseph H. Kraus suggested that 'the heavier odors being assigned to the low notes, and sharp pungent odors to the high notes' and that in order to make one smell more prominent than another 'the loud pedal, or rather in the smell organs, the *strong* odor pedal is trod upon' (Kraus 1922). Both the Piselli’s performance and Kraus’ imagined instrument also suggest that a fan would be used to distribute and then ventilate the odours, so as to clear the room. The need for ventilation in smell performances had already been recognised in the more literary evocations of perfume machines, as in Mayo’s description where the machine itself is located in a room with the perfume tubes at one end and ventilation tubes at the other that sucked scent across the room, through the audience, and then out of the building in order to make room for the next series of perfumed notes.

The idea of the smell organ or piano was intimately linked with practices of composing with smell. When Piesse first imagined the gamut of odours his thoughts were purely centred on the composition of perfumes. The gamut was to be used by professionals to develop chords that would form the basis of their scents. The later (less musical) ‘perfume organ’ used by many perfumers to store their individual ingredients in a semi-circle on their desk was also understood in these terms as an aid to the composition, in this case of perfumes rather than performances.

However, any kind of perfume machine or scent piano might require similar feats of composition. When Lasswitz imagined the ododion of the future he foresaw practices of composition and notation that would enable pieces to be shared and learnt. The 'great masters' of the ododion produced 'a literature of odor-pieces and operas, which, for their originally of conception and their suggestive beauties, soon took rank with the works of the greatest musical composers of former times' (Lasswitz 1879: 6). A smell organ might thus be a tool for composing as well as playing odour-scores. An early imagining of a smell organ, with keys and scent-emitting tubes, published in the French journal L’Illustration in 1844 also suggests the need for inventive new ways of scoring these pieces: here the maestro sits at the organ, his hands on the keys, with a book of music in which a variety of noses appear on the staves in place of musical notation (Bradstreet 2022: 34).

Discussions of smell pianos and perfume machines frequently indicate the need for skill on the part of the player. In Mayo's discussion of a perfume-machine played by a prince in Kaloolah, asserted to his readers that if 'he should ever have an opportunity of sniffing the melodious streams and harmonic accords evolved by a good performer, upon a properly constructed instrument, he will be compelled to admit that his nasal organ was give to him for a higher purpose' (Mayo 1887: 340). However, there is also a question whether, as with the appreciation of music, audiences – imagined or actual – required certain practices of sniffing to full appreciate and engage with a performance on a smell organ. Mayo added that the average audience member

at first… may not appreciate the more recondite combinations and delicate aperfumes, any more than a novice in music appreciates the scientific arrangement of notes in Italian or German opera, but he will at once be able to understand and admire the easy melodies - the natural succession of simple fragrances, and, in time, the cultivated sensibility of his nasal organ will enable him to comprehend the more elaborate harmonies (Mayo 1887: 341).

This was the kind of practice that novelists imagined audiences would have to develop if they were going to engage with a music of odours. Different practices of sniffing were needed when the intention was to tell a story with the smell organ rather than compose a series of harmonies and melodies of scent. In the case of the Piselli’s, a newspaper description of their ‘nose concert’ at the Paris exposition in 1900 reveals the difficulties attendant on matching authorial intention and audience interpretation when it came to smell. The first scent released by the scent organ was that of tar. The journalist described how he

… thought of coal gas, the tragedies so frequently enacted by this popular means of sucide in our capital... But the signora knew better. Her persuasive voice told of the Gulf of Naples, its shipyards and forests of masts, of the red-capped lazzsaroni, of sailors lying on the strand or working because they got tired of being idle ('A Concert in Perfumes', 1900: 876).

In the case of the Piselli’s scent organ, poetic words helped to stabilise the meaning of the odours emitted by their instrument and ensure their correct interpretation by audiences. Later in the performance, the audience manages to recognise the intended scent straight away:

After lunch a stroll into the country. "New-mown hay!" cried six or seven ladies at once, and everybody applauded ('A Concert in Perfumes', 1900: 876).

For the audience there was clearly a pleasure to be derived from correctly recognising the scents as they wafted out from the stage. This involved listening for recognition rather than developing an aesthetic appreciation of smells. However, it also suggests that audiences for smell concerts would be expected to develop their skills in imagining through and with scent. This kind of imaginative engagement, in which the audience members become lost in the scents that emerge from the smell-organ, is on show in Punch’s satirical imagining of a ‘Recital of Smell Harmonies’ in 1935. In this image, a satire on the newly formed ‘Smell Society’, the odours emerge in clouds from long tubes that seem to combine the phonograph speaker and the tubes of an organ. The audience, reclining in their seats with their eyes closed, are lost in a form of olfactory revery (Punch 1935: 63). However, as one of the earliest visualisations of a smell concert suggests, not all audience members might be so enthralled. In the 1844 image of a smell concert in L’Illustration we see the prone bodies of a dead cat and dog, upside down with their legs rigidly pointing skyward as if the symphony of odours had suddenly struck them down (Bradstreet 2022: 34).

The kinds of performances that imagined smell organs and odour pianos could engage in were described as emotional journeys. For example, in Lasswitz's futurological fantasy a piece played on the ododion takes the audience through on a journey of love gained and lost: 

roses, violets, and lilacs called forth memories of that golden springtime when love first budded into bloom. Now this fragrance vanishes, jasmine fills the room; we believe we hold in our hands that bunch of withered flowers whose beauty had vanished even as our young love passed away, and an inexpressible feeling of sadness fills our heart. But there, through all this melancholy, we smell the scorn and the frivolity of the inconstant, conveyed by the aroma of wine, - the presence of alcoholic fumes is more and more perceptible, and now like a cry of horror, - a soul-disturbing discord, - it is powder, and we are surrounded by the odor of the tomb, bringing with it hopelessness and despair (Lasswitz 1879: 7). 

These emotional journeys were, in some accounts, linked to the idea of ‘keys’ borrowed from music. In Mayo’s description of an imaginary perfume-machine his three modulating scents – garlic, musk, and sulphurated hydrogen – offered an opportunity for different forms emotional expression: 

The garlic, which corresponds to the minor key in music, is exceedingly plaintive and affecting. Compositions in this key invariably excite the smeller to tears. Compositions in the musk key are very varied in their expression; sometimes grave and solemn, like church music; at other times gay, lively, and redolent of chalked floors and gaslights. Compositions in the sulphurretted-hydrogen key have invariably a spirit-stirring and martial expression. It is the proper key for odorate marches, battle-pieces, and storm-rondos (Mayo 1887: 340).

Other writers imagined the use of the perfume piano to conjure up memories of the natural world and the passing of seasons. In William Sloane Kennedy’s description of such an instrument he imagined it working as follows:

First, as a crude beginning, suppose the performer wished to compose or play an odor sonata on the seasons he would begin with pulling out the stops for violets and wood anemones and the like for the low preludings touching at the same time those that would emit a pungent savor of the cool forest, then coming in with the pedal for the strong lilac and hyacinth tones and the smell of growing grass and leaves, then in order all the sweet roses and honeysuckles and flowers of hot midsummer not forgetting a discord of a few moments for the rank smell of wayside weeds such as tansy, the carrion flower, the nicotic blooms and ending with the warm aromatic flowers and the asters and the goldenrods of autumn (Kennedy 1897: 16).

The possibilities that smell performances offer for these kinds of journeys continue to the focus of olfactory art and experimentation today. For example, German the artist Wolfgang Georgsdorf, has developed the 'Smeller 2.0' device, described as 'an olfactokinetic art device for composing, producing, interpreting, programming, recording, storing and playing back compositions made up of scents and scent chords'. If such inventions move beyond the territory of conceptual art, we may yet reach the future of rich olfactory compositions imagined by Lasswitz.