AUGURS, in ancient Rome, members of a religious college whose duty it was to observe and interpret the signs (auspices) of approval or disapproval sent by the gods in reference to any proposed undertaking. The augures were originally called auspices, but, while auspex  fell into disuse and was replaced by augur, auspicium was retained as the scientific term for the observation of signs.
The early history of the college is obscure. Its institution has been attributed to Romulus or Numa. It probably consisted originally of three members, of whom the king himself was one. This number was doubled by Tarquinius Priscus, but in 300 B.C. it was only four, two places, according to Livy (x. 6), being vacant. The Ogulnian law in the same year increased the number to nine, five plebeian being added to the four patrician members. In the time of Sulla the number was fifteen, which was increased to sixteen by Julius Caesar. This number continued in imperial times; the college itself was certainly in existence as late as the 4th century. The office of augur, which was bestowed only upon persons of distinguished merit and was much sought after by reason of its political importance, was held for life. Vacancies were originally filled by co-optation, but by the Domitian law (104) the selection was made, by seventeen out of the thirty-five tribes chosen by lot, from candidates previously nominated by the college. The insignia of office were the lituus, a staff free from knots and bent at the top, and the trabea, a kind of toga with bright scarlet stripes and a purple border. The science of augury was contained in various written works, which were consulted as occasion arose: such were the libri augurum, a manual of augural ritual, and the commentarii augurum, a collection of decrees or answers given by the college to the senate in certain definite cases.
The natural region to look to for signs of the will of Jupiter was the sky, where lightning and the flight of birds seemed directed by him as counsel to men. The latter, however, was the more difficult of interpretation, and upon it, therefore, mainly hinged the system of divination with which the augurs were occupied. It was the duty of the augur, before the auspices properly so called (those from the sky and from birds) were taken, to mark out with his staff the templum or consecrated space within which his observations were intended to be made. The method of procedure was as follows. At midnight, when the sky was clear and there was an absence of wind, the augur, in the presence of a magistrate, took up his position on a hill which afforded a wide view. After prayer and sacrifice, he marked out the templum both in the sky and on the ground and dedicated it. Within its limits he then pitched a tent, in which he sat down with covered head, asked the gods for a sign, and waited for an answer. As the augur looked south he had the east, the lucky quarter, on his left, and therefore signs on the left side were considered favourable, those on the right unfavourable. The practice was the reverse in Greece; the observers of signs looked towards the north, so that signs on the right were regarded as the favourable ones, and this is frequently adopted in the Roman poets. The augur afterwards announced the result of his observations in a set form of words, by which the magistrate was bound. Signs of the will of the gods were of two kinds, either in answer to a request (auspicia impetrativa), or incidental (auspicia oblativa). Of such signs there were five classes: (1) Signs in the sky (caelestia auspicia), consisting chiefly of thunder and lightning, but not excluding falling stars and other phenomena. Lightning from left to right was favourable, from right to left unfavourable; but on its mere appearance, in either direction, all business in the public assemblies was suspended for the day. Since the person charged to take the auspices for a certain day was constitutionally subject to no other authority who could test the truth or falsehood of his statement that he had observed lightning, this became a favourite device for putting off meetings of the public assembly. Restrictions were, however, imposed in later republican times. When a new consul, praetor or quaestor entered on his first day of office and prayed the gods for good omens, it was a matter of custom to report to him that lightning from the left had been seen. (2) Signs from birds (signa ex avibus), with reference to the direction of their flight, and also to their singing, or uttering other sounds. To the first class, called alites, belonged the eagle and the vulture; to the second, called oscines, the owl, the crow and the raven. The mere appearance of certain birds indicated good or ill luck, while others had a reference only to definite persons or events. In matters of ordinary life on which divine counsel was prayed for, it was usual to have recourse to this form of divination. For public affairs it was, by the time of Cicero, superseded by the fictitious observation of lightning. (3) Feeding of birds (auspicia ex tripudiis), which consisted in observing whether a bird - usually a fowl - on grain being thrown before it, let fall a particle from its mouth (tripudium sollistimum). If it did so, the will of the gods was in favour of the enterprise in question. The simplicity of this ceremony recommended it for very general use, particularly in the army when on service. The fowls were kept in cages by a servant, styled pullarius. In imperial times decuriales pullarii are mentioned. (4) Signs from animals (pedestria auspicia, or ex quadrupedibus), i.e. observation of the course of, or sounds uttered by, quadrupeds and reptiles within a fixed space, corresponding to the observations of the flight of birds, but much less frequently employed. It had gone out of use by the time of Cicero. (5) Warnings (signa ex diris), consisting of all unusual phenomena, but chiefly such as boded ill. Being accidental in their occurrence, they belonged to the auguria oblativa, and their interpretation was not a matter for the augurs, unless occurring in the course of some public transaction, in which case they formed a divine veto against it. Otherwise, reference was made for an interpretation to the pontifices in olden times, afterwards frequently to the Sibylline books, or the Etruscan haruspices, when the incident was not already provided for by a rule, as, for example, that it was unlucky for a person leaving his house to meet a raven, that the sudden death of a person from epilepsy at a public meeting was a sign to break up the assembly.
Among the other means of discovering the will of the gods were the casting of lots, oracles of Apollo (in the hands of the college sacris faciundis), but chiefly the examination of the entrails of animals slain for sacrifice (see Omen). Anything abnormal found there was brought under the notice of the augurs, but usually the Etruscan haruspices were employed for this. The persons entitled to ask for an expression of the divine will on a public affair were the magistrates. To the highest offices, including all persons of consular and praetorian rank, belonged the right of taking auspicia maxima; to the inferior offices of aedile and quaestor, the auspicia minora; the differences between these, however, must have been small. The subjects for which auspicia publica were always taken were the election of magistrates, their entering on office, the holding of a public assembly to pass decrees, the setting out of an army for war. They could only be taken in Rome itself; and in case of a commander having to renew his auspicia, he must either return to Rome or select a spot in the foreign country to represent the hearth of that city. The time for observing auspices was, as a rule, between midnight and dawn of the day fixed for any proposed undertaking. In military affairs this course was not always possible, as in the case of taking auspices before crossing a river. The founding of colonies, the beginning of a battle, the calling together an army, the sittings of the senate, decisions of peace or war, were occasions, not always but frequently, for taking auspices. The place where the ceremony was performed was not fixed, but selected with a view to the matter in hand. A spot being selected, the official charged to make the observation pitched his tent there some days before. A matter postponed through adverse signs from the gods could on the following or some future day be again brought forward for the auspices. If an error (vitium) occurred in the auspices, the augurs could, of their own accord or at the request of the senate, inform themselves of the circumstances, and decree upon it. A consul could refuse to accept their decree while he remained in office, but on retiring he could be prosecuted. Auspicia oblativa referred mostly to the comitia. A magistrate was not bound to take notice of signs reported merely by a private person, but he could not overlook such a report from a brother magistrate. For example, if a quaestor on his entry to office observed lightning and announced it to the consul, the latter must delay the public assembly for the day.
On the subject generally, see A. Bouché-Leclercq, Histoire de la divination dans l'antiquité (1879), and his articles, with bibliography, in Daremberg and Saglio's Dictionnaire des antiquités, also articles "Augures," "Auspicium," by Wissowa in Pauly's Realencyclopädie (II. pt. ii., 1896), and by L.C. Purser (and others) in Smith's Dictionary of Greek and Roman Antiquities (3rd ed., 1890). (See also Divination, Omen, Astrology, etc.)
 There is no doubt that auspex = avi-spex ("observer of birds"), but the derivation of augur is still unsettled. The following have been suggested: (1) augur (or augus) is a substantive originally meaning "increase" (related to augustus as robur to robustus), then transferred to the priest as the giver of increase or blessing; (2) = avi-gur, the second part of the word pointing to (a) garrire, "chatter," or (b) gerere, the augur being conceived as "carrying" or guiding the flight of the birds; (3) from a lost verb augo = "tell," "declare." It is now generally agreed that the science of augury is of Italian, not Etruscan, origin.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)