by Calder Loth
Senior Architectural Historian for the Virginia Department of Historic Resources.
Member of the Institute of Classical Classical Architecture & Art‘s Advisory Council.
The Roman Forum at its height comprised one of world’s greatest architectural assemblages. Sadly, throughout the Middle Ages and Renaissance its temples and civic buildings were plundered for their materials. The surviving fragments are only hints of this formerly unparalleled splendor. Dominating the Forum’s central area was a magnificent temple of which only three columns remain. Yet these columns and the unique treatment of their capitals have served as models for various, though not numerous works since recorded by Andrea Palladio and published along with his conjectural restoration drawings in I Quattro Libri dell’Architettura or The Four Books on Architecture (1570). We have some idea of what Palladio found to record through Giovanni Piranesi’s famous mid-18th-century view of the Forum, little changed from Palladio’s time two centuries earlier. (Figure 2) The columns stand as lonely sentinels in what had become a cow pasture—the Campo Vaccino.
The three marble columns belong to a rebuilding of an earlier temple by Emperor Tiberius in 6 A.D., but with subsequent restorations. (Figure 3) Later removal of the many layers of earth around the base of the columns has revealed remnants of the high podium on which the temple originally stood. Palladio was somewhat at a loss as to the temple’s identity. He stated that some believed it was dedicated to Vulcan but that others thought it honored Romulus; still others stated it was the Temple of Jupiter Stator (Jupiter the Steadfast), the designation that Palladio accepted. Scholars have since determined that it was dedicated to the demi-god twins, Castor and Pollux, mythical cavalry heroes.
A close-up view of the temple’s capitals shows us their defining features. (Figure 4) The intertwining or interlocking center stems or volutes (sometimes called helices) are unique to this temple. They distinguish the capitals from all other versions of the Roman Corinthian and lend animation to the composition. Regrettably, the corner volutes are long gone from each capital, leaving their exact form subject to interpretation. Surviving in the abacus are fragments of a rinceau of elaborate foliage topped by an egg-and-dart molding. These abacus embellishments are often omitted in modern versions, but the intertwining stems are essential distinguishing features.
Palladio’s detailed recording and later publication of the Castor and Pollux order in Book IV of I Quattro Libri captures the order’s general character and its details. (Figure 5) Yet, as we will note below, Antoine Desgodetz’ more precise examination a century later detected a number of inaccuracies in Palladio’s version. Nevertheless, Palladio’s depiction generated an important early awareness of the order, leading to replications mainly of its capital though usually with simplifications. Provided here is a small sampling, hoping that it will rejuvenate appreciation of this elegant order and encourage us to be on the lookout for more examples. They are always a visual treat.
Palladio’s elevation of the temple in I Quattro Libri is completely conjectural since no remnants of the façade remained at the time of his survey. (Figure 6) Most authorities agree that it had an octastyle portico. The order of the surviving side columns obviously continued onto the portico. Palladio shows eustyle spacing of the columns (the center bay made slightly wider than the flanking bays), a treatment that would have been consistent with most Roman temples and one advocated by Vitruvius. The doorframe design and statues are assumptions. Moreover, Palladio was unaware that the temple stood on a high podium. Other than the podium, subsequent reconstruction images and narrative descriptions differ little from Palladio’s.
Palladio was also the first to attempt a conjectural plan of the temple. (Figure 7) We have to appreciate that Palladio was working with only three columns whose bases were buried at the time. Palladio correctly surmised that the temple was peripteral with an octastyle front, but he guessed that each side had fifteen columns whereas modern archaeologists and scholars have concluded that the sides consisted of eleven columns. He also assumed that the stereobate (the three-step platform) was at grade though excavations have revealed that the temple stood on a tall (nearly 20 feet) arcaded podium which may originally have included a speaker’s platform approached by lateral stairs. Despite its flaws, Palladio’s plan effectively coveys the temple’s monumental character.
One of the earliest reliable depictions of the Castor and Pollux capital appears in Antoine Desgodetz’ Les Édifices Antiques de Rome of 1682. (Figure 8) A stickler for precision, Desgodetz takes Palladio to task for his numerous inaccuracies (not only here but also in his other ancient temple drawings). For instance, Desgodetz states of this order: “Palladio in the abacus of the capital puts a little rose in the middle of the great one, instead of the pomegranate that is there. He makes the large rose of olive-leaves, which is of leaves of parsley. . . . He makes the astragal at the top of the column too high by five twelfths of a part, and too projecting by a half part, the fillet under it too low by the sixth of a part. . . .The capital is too high by two parts two thirds.”  In Desgodetz’ illustration, we see how the intertwining stems have channels and are not flat as Palladio has them, and that the fleuron indeed has a pomegranate bud, not a rose. He continues his critique on many other parts of the order.
A conspicuous but rarely observed use of the Castor and Pollux Corinthian embellishes James Gibbs’s St. Martin-in-the-Fields (completed 1726), one of the most influential church designs of the English-speaking world. (Figure 9) Gibbs makes no mention of the order in his A Book of Architecture (1728). Nor are his various illustrations of the church in this design book detailed enough to discern that his capitals are other than a generic Corinthian order. However, a recent cleaning of St. Martin reveals the capitals to be particularly faithful replicas of the ancient precedents, even including the foliage decoration on the abacus, which most examples avoid. (Figure 10) Whether Gibbs used Palladio’s I Quattro Libri or Desgodetz’ Les Édifices Antiques de Rome as his source is uncertain. Records show that he owned Palladio’s treatise, but not Desgodetz’. Yet Gibbs definitely relied on Desgodetz for details in other of his works.
The Birmingham Town Hall is likely the most ambitious attempt at replication of the Forum’s great temple. (Figure 11) Its architects, Joseph A. Hansom and Edward Welsh, produced a masterpiece of the Classical Revival, a movement that fostered archaeologically correct interpretations of ancient architecture. Like the original temple, the hall is set on a tall arcaded podium. Hansom and Welsh followed Palladio’s ground plan by providing the hall with fifteen columns on each side, seemingly unaware that this was in error. The capitals are close copies of the originals. No steps approached the portico since it was not yet certain whether the temple had steps. Opened in 1834, the hall has served primarily as a concert venue.
Robert Mills chose the Castor and Pollux Corinthian for the order on his 1842 General Post Office, one of the District of Columbia’s most eloquent early public buildings. (Figure 12) Mills accurately reproduced the order for both the engaged and freestanding columns, but used a simplified version for the pilaster capitals, applying only one principal row of acanthus leaves instead of the standard two. (Figure 13) I have illustrated one of the pilaster capitals as they survive in a relatively good state of preservation. The column capitals have suffered significant deterioration caused by the fragile quality of the marble. The building has had a complex expansion. The F Street (north) façade with its recessed portico is an 1855 addition by Thomas U. Walter, which closed in the original U-shaped plan. Though the side elevations have been lengthened, they and the south elevation generally retain the character of Mills’ original design.
Palladio’s dictum that temples should be “built with ample and beautiful proportions, because all grandeur and magnificence is required for divine worship”  gave license to erecting imposing houses of Christian worship in the form of ancient pagan temples. The 1850 Trinity Methodist Church, prominently situated on Charleston’s Meeting Street, evokes this Palladian ideal for temples. (Figure 14) Although local architect Charles C. Jones drew inspiration for its form from the Maison Carrée, he selected the Castor and Pollux Corinthian for its hexastyle portico. The capitals closely match published images, even incorporating the pomegranate bud in the center of the fleuron. (Figure 15) Unfortunately, the right corner capital has lost portions of the intertwining stems. We need to focus on the capital immediately behind it to see this essential detail in undamaged form.
Huge colonnades in the Castor and Pollux Corinthian define the main elevations of San Francisco’s Bank of California. (Figure 16) Designed by the local firm of Bliss & Faville and erected in 1906-1908, the building is a landmark in the heart of the city’s financial district. Walter Bliss and William Faville were both California natives but began their careers in the office of McKim, Mead & White. Except for the order, their design, with its tall bays of bronze lattice, parallels Stanford White’s 1904 Knickerbocker Trust Company (now unrecognizably remodeled). White’s Corinthian capitals were based on the Temple of Mars Ultor as depicted by Palladio. Bliss and Faville may have chosen the Castor and Pollux Corinthian as a reference to the ancient temple’s supplementary function as a depository for Rome’s state treasury. (Figure 17) Like most modern versions, the bank’s capitals lack the foliage decorations on the abacus, but are otherwise handsome adaptations. The bank is one of several buildings designed by Bliss & Faville in the wake of the San Francisco earthquake.
The Museum on Natural History on the National Mall undeservedly receives little attention as a premier monument of the American Renaissance. (Figure 18) Designed by the little-known Washington firm of Hornblower and Marshall, and completed in 1911, the building was originally proposed to be in the French Beaux-Arts style. Through the influence of Charles McKim, an advisor on the Mall’s development, the design was changed to one with a strong Roman character. The resulting scheme is dominated by a central domed section fronted by a Corinthian colonnade. The colonnade provides a base for a massive Diocletian window projecting into an open tympanum. For the colonnade’s order, Hornblower and Marshall chose the Corinthian of Castor and Pollux, all executed in white granite. (Figure 19) Though slightly dimmed by a covering of netting to deter birds, the beautifully carved capitals evoke the imperial splendor of the originals.
We can lament that in recent decades the use of the Castor and Pollux Corinthian has all but vanished from the repertoire of practitioners of classical architecture. Indeed, contemporary examples of the Corinthian order are nearly always generic ones. The Castor and Pollux order was unique to one of the greatest monuments of ancient times, lending elegance and distinction to a temple once dominating the heart of the Roman Empire. It is an order to be kept for special circumstances and not left as an unsung relic in the ruins of the Forum.
 Sebastiano Serlio published a somewhat stylized image of a half capital resembling the Castor and Pollux order but without the entablature. He identified it only as “Colomnes, beside the Colises [Colosseum].” The image appeared in Book IV, Regole generale, published in 1537 as the first installment of his treatise L’Architettura. The full treatise was published in English in 1611.
 Sources are inconsistent as to whether the existing columns date from Tiberius or from reconstructions as late as the sixth century A.D.
 Andrea Palladio, The Four Books on Architecture, Robert Tavenor and Richard Schofield translation (MIT Press, 1997), Book Four, p 67.
 Amanda Claridge, Rome, An Oxford Architectural Guide (Oxford University Press, 1998, p. 91. She states the stairs were later changed to a single flight of front stairs.
 Antoine Desgodetz, The Ancient Buildings of Rome, English translation by George Marshall (London, 1771), Vol. 1, p. 64; ECCO Print Edition.
 Hansom is better known for his many Gothic Revival works and for his invention of the Hansom cab.
 The building ceased its postal service function in 1897. Following housing other government agencies and a period of abandonment, it was restored as the Monaco Hotel, opened in 2002.
 The Four Books on Architecture, Book IV, p. 216
 The church was originally built as a Presbyterian church. The Trinity Methodist congregation purchased the property in 1926 when the Presbyterians moved to an uptown location.
 Founded in 1864, the Bank of California became the Union Bank of California in 1996.