The etheric counterpart of the physical body which, when out of coincidence, may temporarily move about in space in comparative freedom and appear in various degrees of density to others. The belief in the existence of the double, or astral body, is ancient, and its modern use as a "working hypothesis" solves many puzzling problems in psychical research.
The Roman Catholic Church gave tacit approval to such an idea in its consideration of the bilocation of several saints. St. Anthony of Padua, for example, preaching in the Church of St. Pierre du Queyroix at Limoges on Holy Thursday in 1226, suddenly remembered that he was due at that hour at a service in a monastery at the other end of the town. He drew his hood over his head and knelt down for some minutes while the congregation reverently waited. At that moment the saint was seen by the assembled monks across town to step forth from his stall in the monastery chapel, read the appointed passage in the office, and immediately disappear. Similar stories are recorded of St. Severus of Ravenna and St. Ambrose and St. Clement of Rome. The best-known case is dated September 17, 1774. Alphonse de Liguori, imprisoned at Arezzo, remained quiet in his cell and took no nourishment. Five days later he awoke in the morning and said that he had been at the deathbed of the pope.
Though testimonies of seeing doubles and of out-of-the-body travel experiences are numerous, rigid experimental proof is scarce. Colonel Eugerne August-Albert D'Aiglun Rochas was one of the first to attempt to furnish some. During his experiments in the exteriorization of sensitivity he noticed that in subjects in a state of deep hypnosis, the concentric strata around the body—which he induced by suggestion— condensed, right and left, into poles of sensitivity that finally united in a phantasmal enlargement of the body.
This phantom form, which could be lengthened under the order of the magnetizer and could pass through material objects, became the seat of sensation. It could be modeled like wax in the sculptor's hands and when Rochas suggested that a female subject give it her mother's form, the suggestion was successfully carried out. One of these experiments was made in Paris in the presence of A. N. Aksakof with Elizabeth d'Esperance as the seeing subject and a Ms. Lambert as the exteriorizing subject.
Henri Durville was the next experimenter. By means of passes he built up a double around his subjects Ninette and Martha and observed that the double was capable of motor effects at a distance of several rooms. Finally, from an effluvium from the forehead, the bregma, the throat, the epigastrium, and even the spleen, he saw a true phantom take shape at a distance of 20 to 24 inches from the medium. It had the appearance of the medium, became more or less luminous, and was united with the medium's body by a little cord at the navel, the bregma, or the epigastrium.
The phantom could see through opaque bodies in the distance and its objectivity was demonstrated by the increasing brilliance of a calcium sulphide screen when it was asked to approach it. The sensory organs of the medium were seated in the phantom. When approached it produced a sensation of cold, was humid to the touch, and made the fingers luminous in the dark.
The experiments of Dr. Duncan McDougall of Haverhill, Massachusetts, in weighing dying patients appeared to furnish some confirmation. He found that at the moment of death the beam of his scale would suddenly go up. Out of six cases the weight lost at death averaged between 2 and 2.5 ounces, but this might also be accounted for by changes in body fluids or evaporation.
On the basis of some experiments in regression of memory, Rochas believed that the double is only complete at seven years of age and that the astral shape enters the body a little while before birth and then only partially. Dr. Joseph Maxwell studied a very sensitive young woman who was entrusted with bringing up a child from birth. She saw at its side a luminous shadow with features larger and more formed than those of the child. This shadow was further away from the child at its birth. It seemed to penetrate gradually into the body. At 14 months of age the penetration was about two-thirds complete.
Photographic evidence for the double was presented in the works of Gabriel Delanne, Rochas, Durville, Commandant Darget, and Aksakof. The first such pictures were obtained by William H. Mumler, the American practitioner of spirit photography. He was promptly accused of fraud because it was the photograph of someone dead that was expected to appear on his plate. The double of Stainton Moses was photographed in 1875 in Paris by another spirit photographer, Édouard Buguet, while the medium lay in trance in London. This picture, however, was discredited by subsequent disclosures about Buguet.
The experiments of Julien Ochorowicz on the radiography of the etheric body stand in a class of their own. On September 11, 1911, he obtained the photograph of a spirit hand on a sensitive film rolled up and enclosed in a bottle. The film, as it lay rolled in the bottle, measured about three-quarters of an inch in diameter. The bottle had an orifice of about two-thirds of an inch. It was closed with the palm of Ochorowicz's right hand. With his left he laid it on his knee and held it there firmly. The medium, Stanislawa Tomczyk, then placed her two hands on the bottle between his. She seemed excited and exclaimed that she wished that a small hand would appear. Then she said, "It is strange! The bottle seems to enlarge under my fingers; but perhaps this is an illusion. My hands swell, I cease to feel them." An attack of cramping ensued. The medium screamed; a moment or two later Ochorowicz broke the bottle, developed the film, and found on it the imprint of a large hand with the thumb posed in line with the index finger, so that it had room to appear on the film, which was 13 cm wide. The hand looked like that of the medium.
In automatic writing the following explanation came through: "I crept in by a chink between your hand and the orifice of the bottle. Then I slipped my hand flat between the folds of the roll, and the light caused itself, I do not know how, I merely took care to make the film opaque." This communication came from "Little Stasia," Tomzyck's control, whom Ochorowicz suspected for a long time to be the medium's double.
Continuing his experiments, Ochorowicz tried to discover the thickness of the etheric hand. He found that, when materialized, the hand was less than a millimeter thick, and that it was at least very probable that it was flat, and could therefore find room in a space too narrow for a normal hand. The same experiments also assured him that the double could, by autosuggestion, diminish the size of its hand if it met with obstacles (see thoughtforms ).
Projection of the Double
Supposed proof of the double is its experimental projection, often described as "astral" projection, but now classified as "out-of-the-body" travel. Reportedly the usual method of such experiments is to decide before going to sleep to visit someone during the night.
One case, reported in Phantasms of the Living by Edmund Gurney, F. W. H. Myers, and Frank Podmore (1886) is corroborated by the testimony of Stainton Moses, the "Z" of the account:
"One evening early last year, I resolved to try to appear to Z, at some miles distance. I did not inform him beforehand of the intended experiment; but retired to rest shortly before midnight with thoughts intently fixed on Z, with whose room and surroundings, however, I was quite unacquainted. I soon fell asleep, and awoke next morning unconscious of anything having taken place. On seeing Z a few days afterwards, I inquired: 'Did anything happen at your rooms on Saturday night?' 'Yes,' replied he, 'a great deal happened. I had been sitting over the fire with M. smoking and chatting. About 12:30 he rose to leave, and I let him out myself. I returned to the fire to finish my pipe, when I saw you sitting in the chair just vacated by him. I looked intently at you, and then took up a newspaper to assure myself that I was not dreaming, but on laying it down I saw you still there. While I gazed, without speaking, you faded away.' "
The Rev. P. H. Newnham, also quoted in Phantasms of the Living, had a singularly vivid dream. He saw the family of his fiancée, chatted with the father and mother in his dream, bade them goodnight, took a candle, and went off to bed. The he says:
"On arriving in the hall, I perceived that my fiancée had been detained downstairs, and was only then near the top of the staircase. I rushed upstairs, overtook her on the top step, and passed my two arms round her waist, under her arms, from behind. Although I was carrying my candle in my left hand, when I ran upstairs, this did not, in my dream, interfere with this gesture. On this I woke, and a clock in the house struck 10 almost immediately afterwards. So strong was the impression of the dream that I wrote a detailed account of it the next morning to my fiancée. Crossing my letter, not in answer to it, I received a letter from the lady in question: 'Were you thinking about me, very specially, last night just about 10 o'clock? For, as I was going upstairs to bed, I distinctly heard your footsteps on the stairs, and felt you put your arms around my waist.' "
The methods of experimental projection are discussed in Hector Durville 's Le Phantôme des vivants (1909) and in Charles Lancelin's Méthode de dédoublement personel (1913). Another contribution to the subject is in The Projection of the Astral Body, (1929) by Sylvan J. Muldoon and Hereward Carrington. According to this book special exercises are necessary to retain consciousness during projection. Reportedly projection nearly always occurs in the dream state. Muldoon claims that "what is thought to be an 'aura,' resting above sleepers and seen by seers, is in reality the etheric body, out of coincidence a few inches. As a rule, in normal persons, consciousness is lost before this phenomenon begins."
The astral and physical bodies are joined by a cord that may be the "silver cord" in Ecclesiastes (12:16). According to Muldoon and others who claim to have seen it, this cord or cable, which is similar to a newborn's umbilical cord, is attached at various parts of the head or, according to some claims, at the solar plexus; it is a whitish gray color, elastic, and similar to a single strand of cobweb when extended.
Supposedly when slightly out of coincidence, the cord is the diameter of a silver dollar, yet the aura surrounding it gives the impression that it is about six inches thick. It is the conductor of cosmic energy into the physical body, for which the astral body acts as condenser. It delivers "the breath of life" while the finer body is projected.
The awakening of consciousness during any unconscious projection thrusts the astral body back into the physical. Adolphe d'Assier's Posthumous Humanity (1887) contains material about repercussions in general and those claimed to have occurred in witchcraft.
Supposedly in the majority of cases, the projection of the double is involuntary and due to emotional stress. "Examples have come to my knowledge," wrote Jung Stilling, at an early age, "in which sick persons, overcome with an unspeakable longing to see some absent friend, have fallen into a swoon and during that swoon have appeared to the distant object of their affection."
Believers claim danger, anxiety, and mental agony are causes of projection. In Phantasms of the Living more than 40 cases of apparitions of the drowned or nearly drowned are cited. Sometimes they remembered seeing near relations who experienced a visual or auditive sensation or felt sudden fear coupled with the idea of their relative's danger.
Mental preoccupation may also be sufficient to result in such an apparition. According to J. G. Swift M'Neill, M.P., the double of T. P. O'Connor was seen in 1897 in the British House of Commons in his accustomed place, while he was on his way to Ireland to visit a dying parent. There are other cases recorded of members of Parliament being seen in the House of Commons when actually elsewhere.
The so-called premonitions of approach belong to this group. In a letter written from St. Petersburg in 1865 (published in Mrs. Home's biography, p. 240) the famous medium D. D. Home told the story of how his own double was seen by Count Alexis Tolstoy at the railroad station three hours before his actual arrival. In the hotel he found a note waiting from Count Tolstoy expressing joy at his return, and he was mildly reproached by the countess, who also saw him, for not seeming to know her at the station.
The following experience of the poet Goethe is narrated in Phantasms of the Living:
"Wolfgang Goethe was walking one rainy summer evening with his friend K., returning from the Belvedere at Weimar. Suddenly the poet paused as if he saw someone and was about to speak to him. K. noticed nothing. Suddenly Goethe exclaimed: 'My God! If I were not sure that my friend Frederick is at this next moment at Frankfort I should swear that it is he!' The next moment he burst out laughing. 'But it is he—my friend Frederick. You here at Weimar? But why are you dressed so—in your dressing gown, with your nightcap and my slippers here on the public road?' K., as I have just said, saw absolutely nothing and was alarmed, thinking that the poet had lost his wits. But Goethe, thinking only of what he say, cried out again: 'Frederick, what has become of you? My dear K., did you notice where that person went who came to meet us just now?' K., stupefied, did not answer. Then the poet, looking all round, said in a dreamy tone: 'Yes, I understand … it is a vision. What can it mean though? Has my friend suddenly died? Was it his spirit?' Thereupon Goethe returned to the house and found Frederick there already. His hair stood on end. 'Avaunt, you phantom!' he exclaimed, pale as death. 'But my friend,' remonstrated Frederick, 'is this the welcome that you give to your best friend?' 'Ah, this time,' exclaimed the poet, with such emotion, 'it is not the spirit, it is a being of flesh and blood.' The friends embraced warmly. Frederick explained that he had arrived at Goethe's lodging soaked by the rain, had dressed himself in the poet's dry clothing and having fallen asleep in his chair, had dreamed that he had gone out to meet him and that Goethe had greeted him with the words: 'You here! At Weimar? What! With your dressing gown, your nightcap and my slippers here on the public road?' From this time the great poet believed in a future life."
Supposedly sometimes the appearance serves a purpose. James Coates quoted a story from T. P.'s Weekly, for which the editor vouched, of a woman who was on her way to Cambridge to meet her fiancé. At every station where the train stopped she saw the apparition of her fiancé, beckoning her to get out. Finally she told her traveling companion, a gentleman, what she saw. He advised her to get out at the next station if she saw the apparition again. The woman saw the apparition again. She got out at once. So did the gentleman. Shortly afterward the train wrecked and the car in which they had been sitting was demolished. During the time her fiancé was sound asleep in the waiting room at Cambridge, and did not remember having dreamed anything unusual.
Sometimes it is a state of illness that facilitates projection. Andrew Lang saw his friend Q. opening his garden gate and coming up the path, which led toward the window where he was writing, but when he got up to let him in there was nobody there. The same day he learned that Q. was ill in bed at the time his double was seen.
There are instances that indicate that projection may be the result of an accident or a violent impact. William Denton quoted the statement of a man who fell from the scaffolding of a building: "As I struck the ground I suddenly bounded up, seeming to have a new body, and to be standing among the spectators looking at my old one. I saw them trying to bring it to. I made several fruitless efforts to re-enter my body, and finally succeeded."
Quite often there seems to be no known reason for the temporary separation. A. N. Aksakof told of the story of Emilie Sagée, a French schoolmistress in Livonia. For a period of 18 months her double was seen, sometimes at her side, making the same gestures, sometimes out in the garden while Sagée was in the room. The double did not always imitate her movements; sometimes it remained seated while she rose from her chair. As the double became clearer and more consistent, Sagée became more rigid and feeble. She was always unconscious of what happened.
Seeing One's Own Double
Dr. Paul Sollier in his Les Phénomènes d'autoscope (1903) gave a summary of the cases of "vision de soi" of Goethe, Alfred de Musset, Shelley, de Maupassant; of the experiences of Drs. Lassegue, Féré, Rouginovitch, and Lemaitre; and of 12 of his own cases.
Goethe's experience was described in Aus meinem Leben, Dichtung und Wahrheit (1811-22):
"I rode now on the footpath toward Drusenheim, and there one of the strangest presentiments surprised me. I saw myself coming to meet myself, on the same way, on horseback, but in a garment such as I had never worn. It was of light grey mingled with gold. As soon as I had aroused myself from this dream, the vision entirely disappeared. Remarkable, nevertheless, it is that eight years afterward I found myself on the same road, intending to visit Frederika once more, and in the same garment which I had dreamed about and which I now wore, not out of choice but by accident. This wonderful hallucination had a quieting effect on me."
Comparing a large number of cases, Sollier found that the apparition had many degrees—from the simple impression of being in one's own presence to a vision as if seen in a mirror. Any disturbance would make it disappear. When the phantom had different attributes—was smaller in stature, wore different clothes—it might persist for hours in varying intensity. The apparition appeared usually during the evening hours, in states of deep meditation, self-concentration, or under anesthesia. The distance at which it was seen varied from a few yards to close proximity. Sometimes it walked before the subject and vanished all at once; sometimes it turned about or moved to the side and imitated his movements. In most cases it was silent. Occasionally there was a dialogue and difference of opinion between phantom and self.
Exchange of Consciousness
Sollier explained these experiences as hallucinations resulting from a loss of sensibility. In discussing the question in the Revue métapsychique (May-June 1930), Eugèn Osty states that in some cases there is an exchange of consciousness, the double becoming the thinking self.
Tradition says that a vision of self is a sign of approaching death. Queen Elizabeth I of England was said to have been warned of her death by the apparition of her own double. It has been suggested that such cases, by a invention of time, may be phantasmal appearances after death.
In a few instances on record, the double was apparently solid; it could hold a hymn book in the church and could speak. The double of Ophelia Corralès of San Jose, Costa Rica, was heard to sing while the girl was somewhere far away and had no knowledge of her appearance. However, this medium was accused of fraud.
Memories of out-of-the-body travel experiences were reported by many mediums. Emanuel Swedenborg, Andrew Jackson Davis, D. D. Home, Stainton Moses, Elizabeth d'Esperance, Gladys Osborne Leonard, and many others have published descriptions. Cora L. Richmond was said to have remained projected for many days. Supposedly she could perceive and receive the answer to every question—even before its complete formation in thought.
Materialization and the Double
The phantom hands and limbs seen in séances are often believed to be the duplication of the medium. Paraffin molds matched a materialized leg of William Eglinton and impressions of a face and fingers in putty matched Eusapia Palladino (see plastics ).
According to occult philosophy, the double is to be distinguished from the spirit or soul. The double is a vehicle of the spirit and, like the physical body, will later be cast off and deteriorate.
Do animals have doubles? Elliott O'Donnell in his Animal Ghosts (1913) asserts that they do. He states that some friends of his had a cat that was frequently seen in two places at the same time; further, he affirms that there are phantasms of both living and dead dogs in just the same proportion as there are phantasms of both living and dead human beings. He claims of a Virginia lady who had a horse that frequently appeared simultaneously in two places.
Since the mid-twentieth century, the subject of the human double and astral (or etheric) projection has been considered under the designation "out-of-body experience" (OBE). The British scientist Robert Crookall collated and classified hundreds of cases of OBEs and various parapsychologists have conducted experiments in the field, including Charles T. Tart and Karlis Osis. In 1956 Hornell Hart made a survey of reported apparitions of the dead, which he compared with apparitions of living persons when having OBEs.
In 1932 Eileen J. Garrett, who established the Parapsychology Foundation in New York, took part in a successful scientific experiment that involved projecting her double from New York to Iceland under test conditions. This case is described in Garrett's book My Life as a Search for the Meaning of Mediumship (1938).
In the 1970s psychic Ingo Swann worked with Karlis Osis at the American Society for Psychical Research on a series of experiments aimed at demonstrating the existence of the double. Swann, seated in a chair and attached by electrodes to a monitoring device, attempted to project his double to a hidden target. The vision of the double, as opposed to simple clairvoyance, was determined by the angle of vision at which the target objects were viewed. These tests proved most successful and provide some of the best data available on the existence of a human double. Robert A. Monroe, also known for his OBEs, has allowed himself to be tested on various occasions.
Battersby, H. F. Prevost. Man Outside Himself. London, 1942. Reprint, New Hyde Park, N.Y.: University Books, 1969.
Black, David. Ekstasy: Out-of-the-body Experiences. New York: Bobbs-Merrill, 1976.
Crookall, Robert. The Study & Practice of Astral Projection. London, 1961. Reprint, New Hyde Park, N.Y.: University Books, 1966.
Fox, Oliver [Hugh G. Callaway]. Astral Projection. London, 1939. Reprint, New York: University Books, 1962.
Garrett, Eileen J. My Life as a Search for the Meaning of Mediumship. New York: Oquaga Press, 1938. Reprint, New York: Arno Press, 1975.
Green, Celia E. Out-of-the-Body Experiences. Oxford: Institute of Psychophysical Research, 1968. Reprint, New York: Ballan-tine Books, 1973.
Greenhouse, Herbert B. Astral Journey: Evidence for Out-ofthe-Body Experiences from Socrates to the ESP Laboratory. Garden City, N.Y.: Doubleday, 1975.
Monroe, Robert A. Journeys Out of the Body. Garden City, N.Y.: Doubleday, 1971.
Muldoon, Sylvan J., and Hereward Carrington. The Projection of the Astral Body. London: Rider & Co., 1929.
Rogo, D. Scott. Welcoming Silence; A Study of Psychical Phenomena and Survival of Death. New Hyde Park, N.Y.: University Books, 1973.
Shirley, Ralph. The Mystery of the Human Double. London, 1938. Reprint, New Hyde Park, N.Y.: University Books, 1965.
Smith, Susy. The Enigma of Out-of-Body Travel. Garrell Publications, 1965. Reprint, New York: New English Library, 1968.
——. Out-of-Body Experiences for the Millions. New York: Dell, 1968.
Walker, George B. Beyond the Body: The Human Double and the Astral Planes. London: Boston, 1974.
dou·ble / ˈdəbəl/ • adj. 1. consisting of two equal, identical, or similar parts or things: the double doors. ∎ having twice the usual size, quantity, or strength: she sipped a double brandy. ∎ designed to be used by two people: a double bed. ∎ having two different roles or interpretations, esp. in order to deceive or confuse: the furtive double life of a terrorist.2. having some essential part or feature twice, in particular: ∎ (of a flower variety) having more than one circle of petals: large double blooms. ∎ (of a domino) having the same number of dots on each half. ∎ used to indicate that a letter or number occurs twice in succession: “otter” is spelled with a double t.3. Mus. lower in pitch by an octave.• twice as much or as many: the jail now houses almost double the number of prisoners it was designed for I'll pay double what I paid last time.• adv. at or to twice the amount or extent: you have to be careful, and this counts double for older people. ∎ as two instead of the more usual one: she thought she was seeing double.• n. 1. a thing that is twice as large as usual or is made up of two standard units or things: join the two sleeping bags together to make a double. ∎ a double measure of liquor. ∎ a thing designed to be used by two people, esp. a bed or a hotel room: we'll use the bunk beds, you take the double| our rates are $200 per night for a double. ∎ Baseball a hit that allows the batter to reach second base safely: Sabo came home on a double by O'Neill. ∎ a system of betting in which the winnings and stake from the first bet are transferred to a second. ∎ Bridge a call that will increase the points won if the declarer is successful, or increase the penalty points won by the defenders if the declarer fails to make the contract. ∎ Darts a hit on the narrow ring enclosed by the two outer circles of a dartboard, scoring double.2. a person who looks exactly like another: you could pass yourself off as his double. ∎ a person who stands in for an actor in a film. ∎ an apparition of a living person: she had seen her husband's double.3. (doubles) (esp. in tennis and badminton) a game or competition involving sides made up of two players: the semifinals of the doubles. • pron. a number or amount that is twice as large as a contrasting or usual number or amount: he paid double and had a room all to himself.• v. 1. [intr.] become twice as much or as many: profits doubled in one year. ∎ [tr.] make twice as much or as many of (something): Clare doubled her income overnight. ∎ [tr.] archaic amount to twice as much as: thy fifty yet doth double five and twenty. ∎ (double up) use the winnings from a bet as stake for another bet. ∎ (of a member of the armed forces) move at twice the usual speed; run: I doubled across the deck to join the others. ∎ (double up) share a room: “Where's Jimmy going to sleep?” “He can double up with Bert.” ∎ Baseball (of a batter) get a two-base hit: Strawberry doubled with two outs. ∎ Bridge make a call increasing the value of the penalty points to be scored on an opponent's bid if it wins the auction and is not fulfilled. ∎ inf. go out on a double date: they doubled with his sister and her oafish boyfriend.2. [tr.] fold or bend (paper, cloth, or other material) over on itself: the muslin is doubled and then laid in a sieve over the bowl. ∎ [intr.] (double up) bend over or curl up, typically because one is overcome with pain or mirth: Billy started to double up with laughter. ∎ clench (a fist): he had one arm around her and the other fist doubled. ∎ [intr.] (usu. double back) go back in the direction one has come: he had to double back to pick them up. ∎ Naut. sail around (a headland): we struck out seaward to double the headland of the cape.3. [intr.] (of a person or thing) be used in or play another, different role: a laser printer doubles as a photocopier. ∎ [tr.] (of an actor) play (two parts) in the same piece. ∎ Mus. play two or more musical instruments. ∎ [tr.] Mus. add the same note in a higher or lower octave to (a note).PHRASES: on the double at running speed; very fast: he disappeared on the double. ∎ without hesitation; immediately he summoned his officers on the double.double or nothing a gamble to decide whether a loss or debt should be doubled or canceled.DERIVATIVES: dou·bler n.dou·bly adv.
double Dutch language that is impossible to understand, gibberish. The term is recorded from the late 19th century, although high Dutch, in the same sense, is earlier.
double helix a pair of parallel helices intertwined about a common axis, especially that in the structure of the DNA molecule; the structure was originally proposed by Francis Crick (1916–2004) and James D. Watson (1928– ), broadly explaining how genetic information is carried in living organisms and how genes replicate.
double or quits (in the US, double or nothing) a gamble to decide whether a loss or debt should be doubled or cancelled.
doublethink the acceptance of or mental capacity to accept contrary opinions or beliefs at the same time, especially as a result of political indoctrination, coined by George Orwell in his novel Nineteen Eighty-Four (1949).
double whammy a twofold blow or setback; a figurative use of ‘two blows resulting in a knockout’. The original (US) sense of whammy was ‘an evil influence’, and in the 1950s was particularly associated with the comic strip L'il Abner; a double whammy in this context was an intense and powerful look which had a stunning effect on its victims.
Double whammy in its current sense entered the language through modern politics, being given a high profile by Conservative campaigning in the British general election of 1992, with campaign posters on tax policy using the slogan, ‘Labour's double whammy’.
1. (Fr.). A variation, especially one with elaborate ornamentation. Similar to Eng. ‘division’.
2. Indicates a lower octave, e.g. double bassoon plays an octave below bassoon.
3. Singers who perform two roles in one work and instrumentalists who play more than one instr. in a comp. e.g. fl. doubles piccolo.
So double vb. XIII.