Pantheon
3 of the 7 encyclopedias on this shelf carry an entry for Pantheon. Both are reproduced below, so you can see where they agree and where they differ.
Collier's New Encyclopedia (1921)
a Rome, built by M. Agrippa, son-in-law of Augustus, about 27 B. C., and dedicated to Mars and Jupiter the Avenger, in memory of the victory obtained by Augustus over Antony and Cleopatra. The Pantheon is now commonly called the Rotunda, from its circular form. It was given to Boniface IV. by the Emperor Phocas, A. D. 609, and dedicated as a Christian church to the Virgin and holy martyrs, and in 830 Gregory IV. dedicated it to all the saints. It is the finest specimen of a circular building not surrounded by columns. The external diameter is 188 feet, and the height, exclusive of the flat dome surmounting the upper cornice, 102 feet, the dome being 36 feet high. The porch is octastyle, and is 103 feet wide. There is an excellent cast of the Pantheon in the Metropolitan Museum of Art, New York City. Also all the deities collectively worshiped by a nation; the divinities of a nation; and a treatise or discourse upon the collective body of deities of a nation.
Aiton's Encyclopedia (1910)
a famous temple of ancient Rome. It is the largest inclosed building of antiquity. It is trifle larger than the dome of St. Peter's. It was erected by Agrippa about 25 B. C. It was dedicated to all the gods, as the name signifies. The building is circular in shape. The base is 182 feet in diameter. The interior space is hemispherical. It is covered by a dome of circular masonry 142 feet in span, said to be the largest unsupported cupola known in architecture. The top is 141 feet above the pavement. Light is admitted by openings at the apex only. To carry so heavy a dome the walls are of unusual thickness. They contain a number of chapels within themselves. The Pantheon was used as a place of Christian worship for many centuries. It is still standing in a state of excellent preservation. See St. Peter's.
1000 Classical Characters (1900)
A celebrated temple at Rome, built by Agrippa in the reign of Augustus, and dedicated to all the gods. Parcae (The Fates). Powerful goddesses who presided over the birth and life of mankind. They were three in number, Clotho , Lachesis , and Atropos, daughters of Nox and Erebus, according to Hesiod, or, according to what he says in another place, of Jupiter and Themis . 2026 Editor's Note: Although the original temple was commissioned by Agrippa, the current structure was completed by the emperor Hadrian around AD 126. The building's dome remains the world's largest unreinforced concrete dome nearly two millennia after its construction. Since AD 609, the site has functioned as a Catholic church known as the Basilica of St. Mary and the Martyrs. (Ed: BR 2026-06-16)