by Unknown
He [Hadrian] transacted with the aid of the senate all the important and most urgent business and he held court with the assistance of the foremost men, now in the Palace, now in the Forum or the Pantheon or various other places, always being seated on a tribunal, so that whatever was done was made public.8
Written some hundred years after the present Pantheon was built, Dio’s Roman History does not in fact connect its rebuilding with Hadrian, since Dio attributes the building to Agrippa, as is clear from the passage by the same author cited earlier.9 However, the Scriptores Historiae Augustae explained “Agrippa’s” inscription in another way, as an example of Hadrian’s modesty:
He [Hadrian] built public buildings in all places and without number, but he inscribed his own name on none of them except the temple of his father Trajan. At Rome he restored the Pantheon [instauravit Pantheum], the Saepta, the Basilica of Neptune, very many temples, the forum of Augustus, the Baths of Agrippa and dedicated all of them in the names of their original builders.10
For more than a century, this statement has been interpreted to mean that the Pantheon was built entirely during Hadrian’s reign, from the foundation to the dome. But it is intriguing that this emperor’s involvement is described in almost identical terms to the works of repair carried out by his successor, the emperor Antoninus Pius, who, as the Scriptores Historiae Augustae states: “... instauratum ... templum Agrippae.”11 (These repairs, evidently not that extensive, are confirmed by brickstamps.)12
Another inscription, situated on the architrave directly under the more prominent Agrippan one, records repairs carried out by the emperors Septimus Severus and Caracalla, as has also been confirmed by some brickstamps found in the dome and in the intermediate block.13
No known ancient source, then, states that the emperor Hadrian was behind the actual construction of the Pantheon. It has been the brickstamps found in situ and around the monument that have been taken to indicate the Hadrianic date – yet it is precisely on the evidence of brickstamps that this will now be challenged.
2. Dating Roman Buildings by Brickstamps
A walk in Rome today reveals that bricks were quintessential for Roman Imperial buildings, all the more so since so many of them have been stripped of their marble coverings.14 A portion of bricks – we do not know the percentage – were imprinted with stamps (Fig. 3.2).15 These tend to name the owner of the brickworks (often an aristocrat, sometimes even a member of the imperial family), the foreman of the brickworks, very often the name of the operative (usually a slave or a freedman), and the place of production. Such information, frequently heavily abbreviated, could be featured individually or combined, and sometimes accompanied by ornamental symbols. The shape of brickstamps also changed, from the earliest simple rectangular ones used in the first century BC, via the open crescents in vogue toward the end of the first century AD, to crescents that later gradually became more closed, eventually becoming a complete circle during the later empire, when the rectangular-shaped stamps reappear again as well (Fig. 3.3).16
3.2. Brickstamp in situ, Caseggiato del Serapide, Ostia, from the Severan period, ca. AD 193–198. The stamp corresponds to CIL XV 371. (Courtesy of Lynne Lancaster)
3.3. Selected brickstamps, counterclockwise from top left: CIL XV 966.7 (first century BC); CIL XV 315 (Trajanic period, from the Pantheon); CIL XV 20 b (AD 115, from the Pantheon), made from the brickworks owned by M. Rutlius Lupus (hence “MRL”), dated by the name of the consuls Messalla and Pedo; CIL XV 801 (AD 123). (Drawings courtesy of Cesare Mecatti, compiled by Georg Herdt)
Dated brickstamps, that is, ones which mention the names of two consuls (who changed every year), are known from as early as 76 BC on a series of bricks from Velia.17 This was not a geographically isolated case, and dated brickstamps have also been found in other parts of the Italian peninsula, from Bologna in the north to Vibo Valentia in the south.18 Some time in the second decade of the second century AD, brickmakers in Rome also began to adopt this practice.19 The year 123 is particularly prolific for brickstamps; about 280 known types cite the consuls in office that year.20
One of the first major studies on Roman brickstamps was carried out by Gaetano Marini in the late eighteenth century.21 But even before this, stamps from the Pantheon had been described in a less scientific manner by figures such as Ottavio Falconieri and Giovan Battista Piranesi (see Fig. 4.7).22 In a monograph of 1807 on the Pantheon, Carlo Fea concluded that the building was erected by Agrippa, as stated by the inscription, and had later undergone repairs during the reigns of the emperors Domitian, Hadrian, Antoninus Pius, Septimius Severus, and Caracalla.23 This conception was challenged in 1892 when the French architect Georges Chedanne examined the structures and concluded that the whole building had been constructed in Hadrian’s reign.24 Later the same year, Lanciani referred to Chedanne’s discovery as if it were already well known: “non si tratta veramente di scoperta, ma di conferma da fatto già conosciuto.”25 One of the main objectives of the ensuing archaeological excavations, headed by Luca Beltrami in the period 1892–1893, was to check the dating of the rotunda and the portico, and to confirm whether or not the rotunda had been the laconicum of Agrippa’s Baths, an idea advanced by Fea and later replicated by Lanciani. Beltrami’s ensuing publication verified that there were no traces of heating that could have supported the laconicum theory, and more importantly, it concluded that the whole Pantheon was Hadrianic, and sooner or later scholars came to accept this as certain.26
Just before these developments, Heinrich Dressel had been conducting the first methodologically based study on Roman brickstamps, which he published in 1891 as the fifteenth volume of the Corpus Inscriptionum Latinarum (conventionally abbreviated as CIL XV). In the 1930s and 1940s, his work was further developed by the German scholar Herbert Bloch.27 Bloch systemized the corpus of dated brickstamps, and then applied them to the chronology of a long list of buildings in Rome and its surroundings.28 Even if I advance here a different interpretation for the Pantheon to that of Bloch, it remains directly dependent on his method, and on the important discoveries made by him (and by Dressel before him).29 Bloch’s work remains indispensable for the dating of many Roman buildings in Rome, in Ostia, and in Tivoli.
Bloch’s extensive research relied on prosopography, the study of the lives of historical figures, in this case the careers of brickmakers, who can sometimes be tracked as their status changed from slaves to foremen, and even to becoming the owners of brickworks. The information condensed in the stamps changed constantly to reflect such changes of status, and consequently individual molds were used for limited periods only. By cross-referencing this kind of information for stamps dated by virtue of the consuls named with other evidence about the buildings in which they were found (ideally, datable inscriptions), Bloch was able to map out a chronology for undated brickstamps. This important work was later supplemented by the researches of scholars such as E. M. Steinby, and more recently by Janet DeLaine.30
Fundamental as Bloch’s methodology was to the business of dating buildings by means of the brickstamps they may contain, this does not mean that he should never be questioned. In the following pages, I reexamine the basis for dating the initiation of the works on the Pantheon to 118 or 119, near the beginning of Hadrian’s reign.31 Much of the structure of the building is brick-faced concrete (Fig. 3.4), and it is to the stamps on some of its bricks that we now turn.
3.4. Detail of exterior brickwork. (Courtesy of Maxim Atayants)
3. Bloch’s Interpretation
The theory of a Hadrianic date for the Pantheon has been left practically unrevised since 1937–1938. Bloch recorded a total of 184 brickstamps in and around the building.32 Excluding the brickstamps found not in situ or in parts not connected with the Pantheon proper (the so-called eastern wall, most probably part of the neighboring Saepta Julia, the Basilica Neptuni, and all of those found around the building), this still leaves 70 examples.
Just five of these in situ brickstamps bear consu
lar dates. Four of them belong to the years 114, 115 and 116, each of which mentions the same brickmaker, M. Rutilius Lupus. Only one is dated to Hadrian’s reign, in particular the prolific year for brickstamps AD 123, as shown in Table 3.1.
Table 3.1. Dated brickstamps (consular dates) from the Pantheon
* * *
CIL XV no.DateExternal rotundaIntermediate blockTotal
19 a 114 1 1
20 b 115 2 2
23 116 1 1
549 a 123 1 1
* * *
While the consular dated brickstamps represent absolutely dependable evidence for the dating of the building, there are 62 brickstamps that have been dated with reasonable confidence by prosopography to varying time ranges. Of these, 19 brickstamps can be defined within a relatively tight time frame, and all of these are Trajanic/late Trajanic (100–117).33 A larger group of 39 exemplars have been dated to a broader time range, the late Trajanic/early Hadrianic period (these are also dated by prosopography, but it has not been possible to pinpoint them any more precisely).34 Then there are 4 brickstamps that have been dated to the Severan period, which can be attributed to the repair works already mentioned. Finally, there are just 3 brickstamps that have not been dated at all (neither by consular dates nor by prosopography), as shown in Table 3.2.
Table 3.2. Synopsis of the brickstamps from the Pantheon (rotunda, dome, intermediate block)
* * *
DateNos. in situ% in situ
Trajanic 23 32.9
Late Trajanic/early Hadrianic 39 55.7
Hadrianic 1 1.4
Severan/post-Hadrianic 4 5.7
Undated 3 4.3
TOTAL nos. 70 100.0
* * *
In interpreting this material, a striking pattern emerges. Of the stamps that can be dated to either a relatively tight range or a specific year there is a great preponderance of Trajanic examples (4 + 19, equaling 23).35 While it is theoretically possible that many of those in the Trajanic/Hadrianic group could tend toward the later period, the fact remains that there is only a single stamp with an absolutely secure Hadrianic date. Obviously, this creates difficulties for the theory of a Hadrianic dating for the Pantheon. Bloch confronted the problem by repeatedly maintaining that the Trajanic bricks should be understood as vecchie rimanenze dal periodo anteriore – “old remains from the preceding period.”36 He argued that the Trajanic brickstamps could represent superfluous material that had been transported to the site of the Pantheon from other earlier projects in Rome, or that had been stockpiled. This may seem to be a satisfactory explanation, and for almost 70 years it has been accepted as such. However, Bloch was evidently concerned that the hypothesis of “old remains” was not an unassailable justification, for he felt obliged to elaborate his explanations further. He did this by focusing on two particular groups of in situ brickstamps.37 One group comprised the 4 consular dated brickstamps from the years 114 to 116 made by M. Rutilius Lupus. The other group was made by one Anteros Severianus, the name that occurs on 21 brickstamps.
4. Testing Bloch’s Thesis – the “Special” Case of Rutilius Lupus
Bloch assigned the Pantheon to a group of buildings that contained brickstamps made by Rutilius Lupus during the period 114–117 but that were not erected until early in Hadrian’s reign.38 In addition to the Pantheon, this group comprises buildings in Ostia, the so-called Le Quartier des Docks (better known as Portico di Pio), part of the Capitolium Group, the Piccolo Mercato, and Insula I.ix (excluding the Curia), as well as two further buildings in Portus, the Portico di Claudio and the so-called Palazzo Imperiale. In normal circumstances, the presence of numerous bricks stamped with consular dates in the years 114 to 117 would point to a construction date around this time, and so here was a problem for Bloch to negotiate.
That the brickmaker Lupus and M. Rutilius Lupus, the holder of the lucrative office of praefecti Aegypti for the period AD 113–117, were one and the same had already been affirmed by other scholars.39 However, it is Bloch’s idea that while he was away in Egypt, his brickworks would have continued to produce bricks for stockpiling, with none (or few) being actually sold. While the identity of this Rutilius Lupus as the “MRL” on the stamps seems practically certain, the second element in Bloch’s hypothesis, the stockpiling during his stay in Egypt, has never been proved.40 It makes little sense from the point of view of economics. Bloch suggested that Rutilius Lupus was speculating in the hope of obtaining higher prices for bricks that had been cured for longer than normal.41 However, the question of whether any such higher price would have covered the expense of storage, plus a premium for the risk, is left without answer. Bloch assumed that the absence of the emperor Trajan (who was away on a campaign against the Parthians) caused a temporary reduction in building activity in the capital and, moreover, that Rutilius Lupus expected to sell bricks at an inflated price due to increased demand once public building works took off again.42
This may seem plausible, but if so, why did the owners of other brickworks not do the same as Rutilius Lupus? In fact, it seems that Bloch’s hypothesis was above all created to account for the brickstamps of 114–116 found in situ in the Pantheon, while maintaining his theory that the building only started in 118 or 119.
Bloch’s stockpiling theory was endorsed by Axel Böethius, and in particular the claim that bricks cured for a longer period may have obtained higher prices. As support, Boëthius invoked Vitruvius’s treatise on Roman architecture, which recommends a prolonged storage period of two years for sun-dried bricks.43 Vitruvius even reported that the people of Utica only used bricks if they had been stored for five years.44 It is understandable that sun-dried brick masonry could benefit from seasoning, but it is important to point out that they are structurally different from fired bricks.45 Once bricks have been fired, prolonged storage will have brought little additional benefit, and besides, there is at least one documented example of bricks being used a very short period, months, not years, after they were made.46 Through the inscription found on the Serapeum in Ostia, we know that this building was dedicated in AD January 127, yet its fabric contains some brickstamps with the names of the consuls of the year 126 – proving that they must have been used more or less immediately.47 What is perhaps surprising is that it was Bloch who made the discovery. Even so, he maintained the benefit to bricks of being seasoned for a long period; he suggests years. The case of the Serapeum should have led him to question his dating of the whole group of “early Hadrianic” buildings, but evidently this was not something he was prepared to do. Instead, he argued that the Serapeum was an extraordinary case.48
Bloch went even further in defense of his postponement of the use of bricks made in 114–117 by arguing against the chronological distribution of Rutilius Lupus’s bricks in the group of “early Hadrianic” buildings.49 This is a significant point, since a sequence of utilization that more or less matches a chronological progression of stamps implies the direct take-up of production. On the other hand, the jumbling up of stamps of different dates could mean that earlier bricks awaited the later ones before being put to use. In a recent article on building activity in Ostia in the second century AD, Janet DeLaine has pointed out that there is indeed a chronological distribution of brickstamps in the buildings that Bloch had highlighted.50 As DeLaine shows, the buildings situated around the so-called Curia, west of the Capitoline, were built sequentially, as indicated by both the building material, that is, dated brickstamps, and the building technique. The first to be completed (after the Curia) was an industrial building (I.ix.2), situated on the northwestern part of the insula. All of the in situ dated brickstamps are from the year 114, with none later, which indicates construction around 114–115. Clearly built up against this structure on the southwestern side is the Caseggiato del Larario (I.ix.3), and this has brickstamps found in situ only from the years 114 and 115, but none from the years before or after; this would be consistent with works being finished no later than 116. No dated brickstamps have been found in situ
in the third building, the Casa Basilicale (I.ix.1), but since it is built up against I.ix.3, DeLaine concludes that construction took place around 117–118. She therefore dismisses Bloch’s claim that these buildings were all built circa 120. Furthermore, DeLaine has been able to show that another of Bloch’s early Hadrianic buildings, the complex commonly known as the Portico di Pio, likewise consisted of several separate bodies of fabric that had been built in distinct phases from 114 onward.
Another of Bloch’s early Hadrianic group is the so-called Palazzo Imperiale at Portus. He records 21 brickstamps in situ; of these 11 were made by M. Rutilius Lupus and dated by consular names to the year 115, while others are datable to the years 114 and 116.51 There is no reason why the construction of the Palazzo Imperiale was not concluded in or around 117, which increases the likelihood that Bloch’s early Hadrianic buildings were all built (or were substantially under way) in the last years of Trajan’s reign.
There is at least one aspect of Bloch’s theory that seems correct, namely, that the Pantheon was contemporary with the group of early Hadrianic buildings that also contain bricks from Rutilius Lupus’s works – only these buildings were in fact Trajanic.52 Thus, this revision of the dates of the buildings at Ostia and Portus to before 118 (Hadrian returned to Rome for the first time as emperor in July of that year) strengthens the case for bringing forward the dating of the Pantheon, too.
5. Another Special Case?
Bloch maintained that the series of brickstamps belonging to the Pantheon and other buildings that mention the brickmaker Anteros Severianus also represents a special group.53 Those from the Pantheon represent by far the largest group found in situ (CIL XV nos. 811 a–f) in Table 3.3. Twenty-one brickstamps of this type come from the Pantheon proper (internal and external parts of the rotunda, the dome, and the intermediate block), that is, 30 percent of the total. Bloch assigned the 811 d and 811 f stamps to the second decade of the second century AD (these being frequently used in Trajanic buildings), while the series CIL XV 811 a–c he judged to be Hadrianic because they were found in the Pantheon and in Hadrian’s Villa, both of which he believed to have been from this time.