<P> Philosopher Laozi was keeper of books in the earliest library in China, which belonged to the Imperial Zhou dynasty . Also, evidence of catalogues found in some destroyed ancient libraries illustrates the presence of librarians . </P> <P> The Library of Alexandria, in Egypt, was the largest and most significant great library of the ancient world . It flourished under the patronage of the Ptolemaic dynasty and functioned as a major center of scholarship from its construction in the 3rd century BC until the Roman conquest of Egypt in 30 BC . The library was conceived and opened either during the reign of Ptolemy I Soter (323--283 BC) or during the reign of his son Ptolemy II (283--246 BC). An early organization system was in effect at Alexandria . </P> <P> The Library of Celsus in Ephesus, Anatolia, now part of Selçuk, Turkey was built in honor of the Roman Senator Tiberius Julius Celsus Polemaeanus (completed in AD 135) by Celsus' son, Gaius Julius Aquila (consul, 110). The library was built to store 12,000 scrolls and to serve as a monumental tomb for Celsus . The library's ruins were hidden under debris of the city of Ephesus that was deserted in early Middle Ages . In 1903, Austrian excavations led to this hidden heap of rubble that had collapsed during an earthquake . The donator's son built the library to honor his father's memory and construction began around 113 or 114 . Presently, visitors only see the remains of the library's facade . </P> <P> Private or personal libraries made up of written books (as opposed to the state or institutional records kept in archives) appeared in classical Greece in the 5th century BC . The celebrated book collectors of Hellenistic Antiquity were listed in the late 2nd century in Deipnosophistae . All these libraries were Greek; the cultivated Hellenized diners in Deipnosophistae pass over the libraries of Rome in silence . By the time of Augustus there were public libraries near the forums of Rome: there were libraries in the Porticus Octaviae near the Theatre of Marcellus, in the temple of Apollo Palatinus, and in the Ulpian Library in the Forum of Trajan . The state archives were kept in a structure on the slope between the Roman Forum and the Capitoline Hill . </P>

Discuss fully the development of library in the history of mankind