mail: Bill Thayer	Latine	Italiano	Help	Up	Home
The text has been carefully proofread. If you find a mistake though, let me know!

Sextus Iulius Frontinus
On the Water-Management of the City of Rome

De Aquaeductu Urbis Romae

Translated by R. H. Rodgers

1 B 1925 B 1925 Every task assigned by the Emperor demands an earnest sense of responsibility, and whether by a watchful concern which is mine by nature or by loyalty which is sincere and attentive, I am roused not merely to the competent performance of an entrusted task, but even to feel devotion towards it. It happens now that Nerva Augustus,​1 an Emperor whose attitude towards the state is one of special devotion or, perhaps better, of special love, has imposed upon me the duties of water commissioner,​2 a post which relates to matters not only generally useful, but necessary for the health, even the security, of the City, an office which has always been administered by the foremost men of our commonwealth.​3 First and most important of my duties, I think, is to acquaint myself thoroughly with the business I have undertaken, a procedure which I have followed in all prior stages of my career. 2 B 1925 B 1925 I should have thought that no man's performance of duty could be more firmly grounded, nor that there could be any other means of deciding between what to attempt and what to avoid. Nor do I believe that there is anything more disgraceful in a man who bears another's trust than to perform the delegated duties according to instructions received from his own assistants. This will happen of necessity whenever a man in charge suffers from lack of experience and has recourse to the practical skills of his underlings; these lesser persons have roles which are crucial, indeed, but only as attendants, the tools, as it were, in the hands of the director.

2 It is for this reason that I continue the habit I have observed through a good many offices, collecting as I was able facts and data relevant to the general subject, arranging them in an orderly manner and, so, to speak, into a systematic body. This booklet, then, is one to which I shall be able to turn as if to a reference manual for administrative purposes. 3 In other books, which I composed after practical experience, I aimed at being helpful to those who came after me; this booklet, too, may perhaps prove useful to a successor, but since it has been written at the outset of my administration, its first good will be directed towards my own instruction and guidance. 3 B 1925 B 1925 So that I may not seem to have left out anything relevant to the subject as a whole, I shall first set down the names of the waters which flow into the City. Then I shall state by whose agency, under what consuls, and in what year after Rome's founding​4 each of these waters was brought in; next from what places and through what distance each is carried; how much of the course is by subterranean channel, how much on substructures, how much on arches.​5 2 Thereafter I shall give the elevation of each water, an explanation of pipe sizes, what supply each appeared to have and how much it distributed, what distributions were made possible, how much each aqueduct furnishes outside the City​6 in relation to its available supply and how much to each ward within the City, how many delivery-tanks there are (both public and private),​7 and from these how much water is allotted to public works, how much to munera (for so . . . are called),​8 how much to streetside basins;​9 how much is reserved in the name of Caesar, and how much is granted by the emperor's favor for uses of private citizens.​10 Finally I shall rehearse the legal right which governs the drawing of water and the maintenance of the aqueducts, along with penalties which enforce those rights, as established by statute, senatorial resolution and administrative policies of the emperors.

4 B 1925 For 441 years from the founding of the City,​11 the Romans were satisfied with the use of whatever water they drew from the Tiber, from wells, or from springs. To this day springs are revered for their sanctity, and their water is thought to bring health to sick bodies. One thinks of the ancient springs of the Camenae,​12 of the . . .,​13 and of Juturna.​14 There are now, however, nine aqueducts from which water converges into Rome. These are named Appia, Anio Vetus, Marcia, Tepula, Julia, Virgo, Alsietina (which is also called Augusta), Claudia, and Anio Novus.

5 B 1925 In the consul­ship of Marcus Valerius Maximus and Publius Decius Mus [312 B.C.E.], thirty years after the beginning of the Samnite War, the Aqua Appia was brought into the City by the censor​15 Appius Claudius (later called "the Blind").​16 In that year the same man also had charge of constructing the Appian Road​17 from Porta Capena​18 as far as the city of Capua. 2 Appius' colleague in the censor­ship was Gaius Plautius, called Venox for having discovered the veins of this water. 3 But Plautius resigned from the censor­ship before the eighteen months' term had elapsed, deceived by Appius who pretended he would do likewise, and so the name of the aqueduct fell to the credit of Appius alone. Indeed, Appius is reported to have extended his censor­ship by many subterfuges, until he could complete both the road and the aqueduct.​19

4 The starting-point of Appia is on the property of Lucullus,​20 780 paces​21 along a side-road which leaves the Praenestine Road to the left between the seventh and eighth milestones. 5 From the source to Salinae,​22 a place near Porta Trigemina,​23 the conduit has a length of 11,190 paces, of which 11,130 paces are underground channel, and 60 paces of substructure and arches are above ground near Porta Capena.

6 Near Spes Vetus,​24 on the boundary between the Horti Torquatiani and a neighboring park,​25 Appia is joined by a branch called Augusta (added by Augustus​26 as a supplement to this supply): the water-men have called the place where they meet "the Twins." 7 This branch is drawn from a spring near the sixth milestone on the Praenestine Road, 980 paces along a side-road to the left (quite near, in fact, to the Collatian Road). 8 From the source to "the Twins" its underground channel is 6,380 paces in length. 9 Distribution begins at the foot of the Clivus Publicius​27 near Porta Trigemina, the place called Salinae.

6 B 1925 Forty years after Appia was introduced, in the 481st year from the founding of the City, Manius Curius Dentatus, who held the censor­ship with Lucius Papirius Cursor, contracted to bring into the City the Anio aqueduct (now called Anio Vetus). He did so with his personal share of booty captured from Pyrrhus.​28 This was in the second consul­ship of Spurius Carvilius and Lucius Papirius [272 B.C.E.]. 2 Two years later the question of completing the aqueduct was deliberated in the Senate, . . . praetor.​29 3 Then by senatorial resolution Curius, who had let the original contract, and Fulvius Flaccus were appointed as a special two-man board to bring in the water. 4 Within five days of his appointment Curius died; thus the honor of bringing it fell to Fulvius.

5 The starting-point of Anio Vetus is above Tibur,​30 on the Valerian Road at the twentieth milestone, outside the . . . Gate,​31 where it delivers part of its water to supply the Tiburtines. 6 The conduit has a length, owing to the process of levelling, of 43,000 paces: of which 42,779 paces are underground channel, and 221 paces substructure above ground.

7 B 1925 One hundred twenty-seven years later, that is in the 608th year from the founding of the City, in the consul­ship of Servius Sulpicius Galba and Lucius Aurelius Cotta [144 B.C.E.], the conduits of Appia and Anio had fallen into disrepair through long use and their waters were being fraudulently diverted by private individuals. To Quintus Marcius, who held at that time the office of urban praetor,​32 the Senate assigned the task of rebuilding those conduits and reclaiming their water for public purposes. 2 And since the growth of the City seemed to require a more abundant supply of water, to him as well the Senate gave the instruction to take charge of bringing into the City other waters so far as he could. 3 Marcius accordingly repaired the earlier conduits and in a channel of its own he brought into the City a third water, which is named Marcia after the man who initiated the project. 4 We read in Fenestella​33 that the sum of 180,000,000 sesterces​34 was voted to Marcius for these works, and since the term of his praetor­ship was not sufficient for completing the task, it was extended for a second year. 5 At that time the Decemviri,​35 while they were consulting the Sibylline Books for other reasons, are said to have discovered that it was not right for the Marcia, or rather the Anio (for tradition more consistently mentions the latter),​36 to be brought to the Capitol.​37 The matter was debated in the Senate, in the consul­ship of Appius Claudius and Quintus Caecilius [143 B.C.E.], with Marcus Lepidus as spokesman for the Board of Decemviri. And three years later, in the consul­ship of Gaius Laelius and Quintus Servilius [140 B.C.E.], the same matter was raised once again by Lucius Lentulus. But on both occasions the influence of Marcius Rex prevailed,​38 and thus it was that water was brought to the Capitol.

6 The starting-point of Marcia is near the 36th milestone on the Valerian Road, three miles along a side-road to the right as one travels from Rome; it can also be reached from the Sublacensian Road, first constructed under Emperor Nero,​39 near the 38th milestone, within 200 paces to the left. 7 The spring water​40 . . . forms a tranquil pool,​41 deep green in color. 8 From this source to the City the conduit has a total length of 61,710½ paces: 54,247½ paces of underground channel, 7,463 paces above ground. Of the latter, there are 463 paces on arches in several places where it crosses valleys at some distance from the City; nearer the City, from the seventh milestone, 528 paces on substructures, the remaining 6,472 paces on arches.

8 B 1925 Gnaeus Servilius Caepio and Lucius Cassius Longinus, called Ravilla, were censors in the 627th year from the founding of the City, in the consul­ship of Marcus Plautius Hypsaeus and Marcus Fulvius Flaccus [125 B.C.E.]. In this capacity they arranged for bringing the water called Tepula from the property of Lucullus (which some persons consider to be Tusculan territory)​42 to Rome and to the Capitol. 2 Tepula's starting-point​43 is near the tenth milestone on the Latin Road, along a side-road two miles to the right. It once was conducted from that point to the City in a channel of its own.

9 B 1925 Later, when the Emperor Caesar Augustus was consul for the second time, with Lucius Volcacius [33 B.C.E.], in the 719th year from the founding of the City, Marcus Agrippa, holding an exceptional aedile­ship after having been consul for the first time,​44 gathered the separate supply of another water near the tenth milestone on the Latin Road, along a side-road two miles to the right, and he blocked off the channel of Tepula. 2 To this newly added water the name Julia was given, after the man who had conceived of the project,​45 but Julia's delivery was so arranged that the name of Tepula remained.

3 The conduit of Julia has a total length of 15,426 paces: 8,426 paces of underground channel, 7,000 paces above ground. All of the latter are near the City, from the seventh milestone: 528 paces on substructures, the remaining 6,472 paces on arches.

4 Past the source of Julia flows the brook called Crabra. 5 This water Agrippa left untouched, whether because he had condemned it for poor quality or because he believed it should be left to the landholders of Tusculum (for it is the Crabra water which all villas in that neighborhood receive in turn, the apportionment made by scheduled days and in fixed quantities). 6 Members of our water staff, however, have not shown the same restraint. They have instead regularly claimed a part of the Crabra to supplement Julia — not to increase Julia's official supply, but to compensate for what they were diverting by unauthorized deliveries for personal profit. 7 Crabra has, therefore, been separated and, at the emperor's order, restored entirely to the Tusculans. They draw it now, not perhaps without astonishment and unaware of the circumstances to which they owe the unusual abundance. 8 Julia, on the other hand, now that the surreptitious taps have been removed, has maintained its supply despite a remarkable drought.

9 In the same year Agrippa reconstructed the conduits of Appia, Anio, and Marcia, which were in very poor condition, and with unique personal initiative he provided the City with a large number of public fountains.

10 B 1925 After an interval of thirteen years since he had brought Julia, and after he had been consul for a third time,​46 in the consul­ship of Gaius Sentius and Quintus Lucretius [19 B.C.E.], this same Agrippa developed another source on the property of Lucullus​47 and brought Virgo into Rome. 2 The date on which this water first came forth in the City is recorded as the 9th of June. 3 It was called Virgo, because a young girl indicated certain water veins to the soldiers who were hunting for water, and the diggers who were to pursue them summoned up an enormous quantity of water. 4 A painting which represents this origin is displayed in a small shrine set up near the source.

5 The starting-point of Virgo is near the eighth milestone on the Collatian Road; and because this is a marshy area,​48 there is an enclosure with concrete to contain the water which issues forth in this spot.​49 6 The supply is augmented by a number of additional tributaries. 7 The length is 14,105 paces: 12,865 paces of underground channel, 1240 paces above ground. Of the latter, 540 paces are on substructures at various points, 700 paces on arches. 8 Subterranean channels of the tributaries total 1,405 paces.

11 B 1925 I do not clearly understand what motivated Augustus, an emperor whose energies were most conspicuously devoted to matters of public interest, to bring in the Aqua Alsietina (which is also called Augusta). It has no commendable quality; indeed, it is so thoroughly unwholesome that it is nowhere delivered for use by the populace. It may be that when Augustus set about building his Naumachia​50 he brought in this water in a conduit of its own to avoid drawing upon more wholesome supplies; what then became surplus for the Naumachia he granted to adjacent properties and for purposes of private irrigation. 2 Yet in the ward across the Tiber it is customary to draw from Alsietina as an emergency reserve for the public fountains, whenever bridges are being rebuilt and water is cut off from this side of the river.

3 The water comes from Lake Alsietinus,​51 the intake being located 6,500 paces along a side-road to the right which leaves the Claudian Road at the fifteenth milestone. 4 Its conduit has a total length of 22,172 paces: 21,814 paces of underground channel, 358 paces on arches.

12 B 1925 As a supplement to Marcia, when needed in periods of drought, Augustus conveyed another water of the same excellent quality by an underground channel leading to the channel of Marcia.​52 This is called Augusta from the name of its donor. 2 Its source is beyond Marcia's spring; its conduit, up to the junction with Marcia, measures 800 paces.

13 B 1925 Later still, Gaius Caesar, the successor of Tiberius,​53 began two new aqueducts, since the seven already in existence now seemed inadequate for public needs and private pleasures. He did so in the second year of his reign, which was in the consul­ship of Marcus Aquila Julianus and Publius Nonius Asprenas [38 C.E.], the 789th year from the founding of the City. 2 This undertaking Claudius brought to a most spectacular completion,​54 with ceremonies of dedication held on the 1st of August​55 in the consul­ship of Faustus Sulla and Salvius Otho [52 C.E.], the 803rd year from the founding of the City.​56 3 One of these waters, drawn from springs called Caerulus and Curtius, was named Claudia.​a 5 The other came to be called Anio Novus ("the New Anio") as a convenient distinction, because there were now two Anio aqueducts flowing to the City. To the earlier Anio the byname Vetus ("the Old") was appended.

14 B 1925 Claudia's starting-point​57 lies just under 300 paces along a side-road to the left which leaves the Sublacensian Road near the 38th milestone. There are two very copious and beauti­ful springs, Caerulus (the name denoting its blueish color) and Curtius.​58 2 Claudia also receives the spring called Albudinus,​59 which is of such excellent quality that, whenever Marcia too needs supplementing, this water serves the purpose so well that it can be added without affecting Marcia's quality in the slightest degree. 3 The spring of Augusta, because it was plain that Marcia's own source was adequate, was diverted into Claudia; but it was not forgotten that Augusta was intended as a reserve for Marcia, so Augusta's water was to serve Claudia only when the conduit of Marcia could not carry it.

4 Claudia's conduit has a total length of 46,230 paces:​60 36,230 paces of underground channel, and 10,176 paces above ground. Of the latter, 3076 paces are on arches at various points in the upper part of its course; nearer the City, from the seventh milestone, there are 609 paces on substructures, and 6,491 paces on arches.

15 B 1925 Anio Novus begins in the Simbruine district,​61 near the 42nd milestone on the Sublacensian Road. Water is taken from the Anio River, along which are cultivated fields with rich soil; the banks are thus rather loose, and so this water runs muddy and turbid even without the adverse effect of rainstorms. 2 For this reason a settling-tank was put in at the intake, where the water might settle and clarify itself between the river and the aqueduct channel.​62 3 Even so, whenever storms occur, the water reaches the City is in a discolored condition. 4 Tributary to Anio Novus is the Herculean Brook, the source of which is near the 38th milestone on the same road, in the vicinity of Claudia's springs but on the opposite side of the river and the road. 5 This source is by nature very clear, but by admixture it loses the charm of its purity.

6 The conduit of Anio Novus has a total length of 58,700 paces:​63 49,300 paces of underground channel, 9400 paces above ground. Of the latter, 2300 paces are on substructures or arches at various points in the upper part of its course; nearer the City, from the seventh milestone, there are 609 paces on substructures, 6491 paces on arches. 7 These are very high arches, rising at certain points to 109 feet.​64

16 B 1925 With these grand structures, so numerous and indispensable, carrying so many waters, who indeed would compare the idle Pyramids or other useless, although renowned, works of the Greeks?​65

17 B 1925 It has seemed to me not inappropriate to set forth both the overall length of each aqueduct's conduit as well as the lengths of its parts according to types of construction. 2 A foremost duty of this office lies in responsibility for their upkeep, and the man at the head ought to know which matters require greater expenditures. 3 In accordance with my official concern, I feel that it is not enough to have made a personal inspection of details. I also had diagrams made of the aqueducts, that from these might be seen where there are valleys and of what size, where rivers are crossed, and where channels contoured along the mountainsides require greater and constant attention for maintenance and repair.​66 4 The usefulness of these diagrams is such that without delay we can have an area of interest in plain view, so to speak, and we can consider the problem as though we were standing on the spot.

18 B 1925 Each of the aqueducts reaches the City at a different level.​67 2 Thus the water of some is available for higher places, while that of others cannot be raised to more elevated sites (for even the hills have gradually grown higher with rubble in consequence of frequent fires). 3 There are five aqueducts whose level ensures that their water will reach every part of the City, but some of these are delivered under greater head, others under less. 4 Highest of all is Anio Novus, next is Claudia, Julia takes third place, Tepula fourth, and last comes Marcia. At its source Marcia is equal in level even to Claudia,​68 but the men of former days engineered its delivery at a lower altitude, either because the technique of levelling had not yet been precisely developed,​69 or because they sank the aqueducts deliberately beneath the ground to avoid an easy opportunity for hostile interruption (there were still in those times frequent wars waged with the Italians).​70 5 But now, whenever a conduit is beyond repair because of its age, in certain places, to save length, the circuitous underground route is abandoned and substructures and arches are used to cross valleys.​71 6 Anio Vetus takes sixth place. Like the five just mentioned, it too would supply higher places in the City if it had been raised on substructures and arches wherever required by the nature of valleys and low-lying terrain. 7 Next in level comes Virgo, then Appia. Both of these were brought in from points near the City​72 and could not be raised to such high elevations. 8 Lowest of all is Alsietina,​73 which supplies the ward across the Tiber and extremely low areas.

19 B 1925 Six of these waters are received in covered settling-tanks located this side of the seventh milestone on the Latin Road.​74 Here they take a breath, as it were, after ra­cing through their channels and here they deposit their sediment. 2 Their quantity also is calculated from gauges set up here.​75 3 At one and the same spot emerge Julia, Marcia, and Tepula. (The latter of these had once run in Julia's channel, but — as I explained above​76 — it was cut off and Tepula now receives its supply at Julia's tank and from this point only it has a conduit of its own and a separate identity.) These three are carried upon the same arches from the settling-tanks onward: 4 topmost is Julia's channel, next below is Tepula's, and then Marcia's. 5 At the elevation of the Viminal Hill they run for a short distance beneath ground level,​77 as far as Porta Viminalis,​78 6 where they emerge again. 7 Earlier, however, a portion of Julia is diverted at Spes Vetus, taken for delivery-tanks on the Caelian Hill. 8 Marcia, too, at a point behind the Horti Pallantiani,​79 pours a portion of its water into the so-called Herculean Channel. 9 This conduit traverses the Caelian, although it furnishes nothing for use on that hill because it is too low in level, and it ends above Porta Capena.​80 20 B 1925 Anio Novus and Claudia are carried from their settling-tanks​81 on a second, loftier, arcade, Anio being the higher of the two. 2 These arches end behind the Horti Pallantiani and from that point their waters are distributed in pipes for the use of the City. 3 Near Spes Vetus, however, Claudia first transfers a part of its supply to the so-called Neronian Arches.​82 4 These follow a line across the Caelian Hill and come to an end alongside the Temple of the Deified Claudius.​83 5 The quantity which they receive they furnish partly to the Caelian itself, partly to the Palatine and Aventine, and to the ward beyond the Tiber.​84 21 B 1925 Anio Vetus also has a settling-tank, located this side of the fourth milestone on a service-road​85 which runs between the arches, from the Latin Road to the Labican Road. 2 Then, within the second milestone, it delivers part of its supply into the so-called Octavian Conduit.​86 This extends to the area along the New Road near the Horti Asiniani from where it is distributed through that district.​87 3 The main conduit of Anio Vetus passes near Spes Vetus, comes inside the Porta Esquilina,​88 and is distributed through the City in deep channels. 22 B 1925 Neither Virgo nor Appia nor Alsietina has a receiving basin or settling-tank. 2 Virgo's arches begin below the Horti Luculliani;​89 they end in the Campus Martius alongside the front of the Saepta.​90 3 Appia's channel passes beneath the Caelian Hill and the Aventine and it emerges, as I said, at the foot of the Clivus Publicius.​91 4 The conduit of Alsietina ends behind the Naumachia, the object for which it was apparently constructed.​92

23 B 1925 Since I have dealt with the persons involved in the introduction of each aqueduct, the dates of construction, along with the location of their starting-points, the lengths of their channels and the sequence of their levels, it seems to me not inappropriate to add further details. I mean now to show how great is the supply which satisfies not only the necessary uses and reserves (both public and private) but those which give pleasure as well, through how many delivery-tanks and to what wards the water is distributed, how much outside the City, how much within the City itself; how much is delivered to streetside basins, how much to munera, how much to public works, how much reserved in Caesar's name, how much granted for private purposes. 2 But before I discuss the names of the 5‑pipe, the 100‑pipe, and those of other pipes by which measurements are determined, I think it methodical to point out the origin of these pipes, their authoritative status, and what each name means. I shall set forth the rule according to which their sizes are reckoned methodically, and then I shall show by what logic I found discrepancies and what steps I took to correct them.

24 B 1925 Water pipes have been calibrated to measurement either in digits or in inches. Digits are employed in Campania and in most parts of Italy, but inches are still accepted as standard in Apulia. 2 A digit, by convention, is one-sixteenth part of a foot, while an inch is one-twelfth.​93 3 Just as there is a distinction between the inch and the digit, there are also two kinds of digits. 4 One is called square, the other round. 5 The square digit is larger than the round by three-fourteenths of its own size; the round digit is smaller than the square by three-elevenths of its size (because, of course, the corners are taken away).​94 25 B 1925 Later, a pipe called the 5‑pipe (quinaria) came into use in the City to the exclusion of all former sizes. Its origin was based neither on the inch nor on either of the two kinds of digit. Some think that Agrippa was responsible for its introduction, others that this was done by the lead-workers under the influence of the architect Vitruvius.​95 2 Those who credit Agrippa with its currency derive its name from the suggestion that into one such pipe were combined five of the slender ancient pipes (we might say little tubes) used for distributing the supply of water which in those times was not copious. Those who ascribe the 5‑pipe to Vitruvius and the lead-workers suppose that its origin lay in produ­cing a cylindrical pipe from a sheet of lead five digits in width. 3 The latter explanation is inexact, because in forming a cylindrical shape the inner surface is contracted while the outer surface is extended. 4 Most probable is the explanation that the name of the 5‑pipe came from its diameter of five quarter-digits, 5 according to a system which remains consistent in pipes of increasing size up as far as the 20‑pipe: the diameter of each increases in size by the addition of one quarter-digit. For example, the 6‑pipe has a diameter of six quarter-digits, the 7‑pipe has seven, and so on by uniform increment up to a 20‑pipe.

26 B 1925 The size of any pipe is determined either by its diameter, or its circumference, or the measure of its delivery-tank; from any one of these factors its capacity is evident.​96 2 That we may more conveniently distinguish between the inch, the square digit, the round digit, and the 5‑pipe itself, we need to treat "the quinaria" (5‑pipe equivalent) as a unit of capacity, for its size is most accurate and its standard best established. 3 The inch pipe has a diameter of 1⅓ digits; its capacity is a little more than 1⅛ quinariae, the fraction being ⅛ plus ³⁄₂₈₈ plus ⅔ of another ¹⁄₂₈₈.​97 4 A square digit converted to circular shape​98 has a diameter of 1⁵⁄₃₆ digits; its capacity is ⅚ of a quinaria. 5 A round digit has a diameter of 1 digit; its capacity is ²³⁄₃₆ of a quinaria. 27 B 1925 Now the pipes based on the 5‑pipe are increased in size in two ways. 2 One is by multiplying the 5‑pipes themselves, that is by including the equivalent of several 5‑pipes into one opening, with the size of that opening increasing according to the addition of more 5‑pipe equivalents. 3 This approach is more or less limited to instances where a number of quinariae have been granted: to avoid tapping the conduit too often, a single pipe is used to lead the water into a delivery-tank, and from here individual persons draw off their respective shares.​98 28 B 1925 The second way does not involve an increase in pipe size related to a necessary number of 5‑pipes. Instead, the increase is in the diameter of the pipe itself, a change which alters both its name and its capacity. Take, for example, the 5‑pipe: add a sixth quarter-digit to its diameter, and one has a 6‑pipe, 2 but the capacity is not increased by an entire 5‑pipe equivalent (it has only 1⁷⁄₁₆ quinariae). 3 By adding quarter-digits to the diameter in the same manner, as already explained, one gets larger pipes, a 7‑pipe, an 8‑pipe, and so on up to the 20‑pipe. 29 B 1925 Beyond the 20‑pipe the gauging is based on the number of square digits which are contained in the cross-section, that is the opening, of each pipe. From this same number the pipes also take their names. 2 Thus that pipe with an area of 25 square digits is called the 25‑pipe; likewise the 30‑pipe, and so on by increase in square digits, up to the 120‑pipe. 30 B 1925 The 20‑pipe is on the borderline between the two methods, and in its case the two sorts of gauging nearly coincide. 2 According to the method applied to smaller pipes, its diameter is 20 quarter-digits (the equivalent of 5 digits); according to the method applied to larger pipes, it has an area just a small bit less than 20 square digits.​100

31 B 1925 The gauging of all pipes from the 5‑pipe to the 120‑pipe is followed in the ways I have explained, and within the appropriate scheme the system is consistent. 2 It also conforms to the pipe sizes set down in and legalized by the records of the emperor.​101 3 Choose, then, mathematical accuracy or imperial authority: on the grounds of either the recorded pipe sizes admit of no uncertainty. 4 Now in most instances members of the water staff have adhered to the unambiguous system, but in four of these pipes they have made deviations, namely the 12-, 20-, 100-, and 120‑pipes. 32 B 1925 In the case of the 12‑pipe, to be sure, the error is not great, nor is this size in common use. 2 To its diameter they added a fraction of a digit (¹⁄₁₆), to its capacity accordingly a small fraction of a quinaria. 3 But in the other three pipes a greater discrepancy is detected. 4 The 20‑pipe they make smaller by half a digit in diameter, which reduces its capacity by 3¹⁄₂₄ quinariae; 5 and they make widespread use of this pipe for deliveries. 6 On the other hand, they have enlarged, rather than diminished, the 100‑pipe and the 120‑pipe, sizes they use regularly for receiving water. 7 To the diameter of the 100‑pipe they add ¹⁷⁄₂₄ of a digit, which increases the capacity by 10¹⁷⁄₂₄ quinariae. 8 To the diameter of the 120‑pipe they add 3⅝ digits, which increases the capacity by 66⅙ quinariae. 33 B 1925 When the water-men subtract on the one hand from the 20‑pipe (by which as a rule they make deliveries) and add on the other hand to the 100- and 120‑pipes (by which they always receive), there are improperly diverted 27 quinariae in the case of the 100‑pipe and 86 quinariae in that of the 120‑pipe.​102 2 While this state of affairs is confirmed by calculation, it is otherwise perfectly and completely obvious.3 From the 20‑pipe, to which Caesar assigns 16 quinariae, they deliver no more than 13, and from the 100‑pipe which they have enlarged it is equally certain that they deliver only up to the official number, it being in this case smaller. Of this there is no doubt, for when his records show grants totalling 81½ quinariae from a 100‑pipe (or 98 quinariae from a 120‑pipe), Caesar makes no further distribution, the official assumption being that the pipe, as it were, has run dry. 34 B 1925 To put the matter simply, there are 25 pipes, 2 all of which — excepting only these four which the water-men have modified — follow the systematic pattern of sizes and are in agreement with the recorded capacities. 3 Everything, as a matter of fact, embraced by measurement must conform to exact, inflexible, and self-evident rules, for only thus will a particular scheme accord with general truths. 4 Compare, for instance, the fixed relation­ship which exists between a quart and a peck, or that between a bushel and either quart or peck.​103 In exactly the same manner the multiplication of quinariae in larger pipes must proceed according to the rule. 5 When, however, the facts disclose a smaller quantity in the pipe used for delivery but a surplus in the receipts, it is plain that we are dealing not with error, but with fraud.

35 B 1925 We remember that water coming from a higher place and reaching the delivery-tank within a short distance does not merely correspond to the expected quantity but rather exceeds it; coming from a lower place, that is with lesser head, and over a greater distance, it is diminished in quantity by the slowness of the channel. Accordingly the water must be "burdened" or "relieved" in respect to delivery.​104 36 B 1925 But the setting of the pipe has also an effect. 2 Placed at right angles and levelled horizontally, it maintains the defined quantity. Positioned alongside the flow of water and sloping downward, it receives more; turned backwards towards the flow of water and sloping upward, its flow is slower and a small quantity. 3 There is also a special bronze fitting, called a calix,​105 which is inserted into either the channel or the delivery-tank, and it is to this that the lead pipes are attached. 4 The calix is to have a minimum length of 12 digits, its opening (that is, its capacity) determined by the amount of water officially granted. 5 The device seems to have been invented because the hardness of bronze is more difficult to bend, so the aperture cannot be expanded or contracted at whim.​106

37 B 1925 I have listed below the standard sizes of all 25 pipes, although only 15 of them are in common use. These figures reflect the methodical system of which I have spoken, and I have corrected those four pipes which the water-men modified. 2 All pipes to be put into use in future should conform to these exact specifications. If the anomalous sizes remain in place, their actual capacity should be reckoned in quinariae. 3 Pipes not used are so noted in their respective cases.​107

39 B 1925 The 5‑pipe (quinaria): diameter 1¼ digits, circumference 3⁸⁹⁄₉₆ digits; capacity 1 quinaria.

40 B 1925 The 6‑pipe: diameter 1½ digits, circumference 4¹⁰³⁄₁₄₄ digits; capacity 1¹¹³⁄₁₄₄quinariae.

41 B 1925 The 7‑pipe: diameter 1¾ digits, circumference 5½ digits; capacity 1²³⁄₂₄ quinariae. Not in use.

42 B 1925 The 8‑pipe: diameter 2 digits, circumference 6⁴¹⁄₁₄₄ digits; capacity 2¹⁶¹⁄₂₈₈ quinariae.

43 B 1925 The 10‑pipe: diameter 2½ digits, circumference 7²⁴⁷⁄₂₈₈ digits; capacity 4 quinariae.

44 B 1925 The 12‑pipe: diameter 3 digits, circumference 9⁴¹⁄₉₆ digits; capacity 5¹⁰⁹⁄₁₄₄ quinariae. Not in use. 2 The water-men's 12‑pipe had a diameter of 3¹⁄₁₆ digits, with a capacity of 6 quinariae.

45 B 1925 The 15‑pipe: diameter 3¾ digits, circumference 11¹¹³⁄₁₄₄ digits; capacity 9 quinariae.

46 B 1925 The 20‑pipe: diameter 5 digits, circumference 15⁴¹⁄₄₈ digits; capacity 16⁷⁄₂₄ quinariae. 2 The water-men's 20‑pipe had a diameter of 4½ digits, with a capacity of 13 quinariae.

47 B 1925 The 25‑pipe: diameter 5¹⁸⁵⁄₂₈₈ digits, circumference 17³⁵⁄₄₈ digits; capacity 20³⁵⁄₉₆ quinariae. Not in use.

48 B 1925 The 30‑pipe: diameter 6¹⁷⁄₉₆ digits, circumference 19⁵⁄₁₂ digits; capacity 24¹²⁵⁄₂₈₈ quinariae.

49 B 1925 The 35‑pipe: diameter 6⁹⁷⁄₁₄₄ digits, circumference 20²⁸¹⁄₂₈₈ digits; capacity 28⁴⁹⁄₉₆ quinariae. Not in use.

50 B 1925 The 40‑pipe: diameter 7¹³⁄₉₆ digits, circumference 22⁶¹⁄₁₄₄ digits; capacity 32⁷⁄₁₂ quinariae.

51 B 1925 The 45‑pipe: diameter 7⁴¹⁄₇₂ digits, circumference 23¹¹³⁄₁₄₄ digits; capacity 36⁴⁷⁄₇₂ quinariae. Not in use.

52 B 1925 The 50‑pipe: diameter 7²⁸¹⁄₂₈₈ digits, circumference 25⁷⁄₉₆ digits; capacity 40²⁰⁹⁄₂₈₈ quinariae.

53 B 1925 The 55‑pipe: diameter 8⁶⁵⁄₁₄₄ digits, circumference 26⁸⁵⁄₂₈₈ digits; capacity 44¹¹⁵⁄₁₄₄ quinariae. Not in use.

54 B 1925 The 60‑pipe: diameter 8⁷¹⁄₉₆ digits, circumference 27¹³³⁄₂₈₈ digits; capacity 48²⁵¹⁄₂₈₈ quinariae.

55 B 1925 The 65‑pipe: diameter 9³⁄₃₂ digits, circumference 28⁷⁄₁₂ digits; capacity 52¹⁷⁄₁₈ quinariae. Not in use.

56 B 1925 The 70‑pipe: diameter 9⁷⁄₁₆ digits, circumference 29⅔ digits; capacity 57⁵⁄₂₈₈ quinariae.

57 B 1925 The 75‑pipe: diameter 9³⁷⁄₄₈ digits, circumference 30¹⁷⁄₂₄ digits; capacity 61¹³⁄₁₄₄ quinariae. Not in use.

58 B 1925 The 80‑pipe: diameter 10¹³⁄₁₄₄ digits, circumference 31²⁰⁵⁄₂₈₈ digits; capacity 65⅙ quinariae.

59 B 1925 The 85‑pipe: diameter 10¹¹⁵⁄₂₈₈ digits, circumference 32¹¹⁄₁₆ digits; capacity 69¹⁷⁄₇₂ quinariae. Not in use.

60 B 1925 The 90‑pipe: diameter 10¹⁰¹⁄₁₄₄ digits, circumference 33⁶¹⁄₉₆ digits; capacity 73⁸⁹⁄₂₈₈ quinariae.

61 B 1925 The 95‑pipe: diameter 10²⁸⁷⁄₂₈₈ digits, circumference 34¹⁶¹⁄₂₈₈ digits; capacity 77⁵⁵⁄₁₄₄ quinariae. Not in use.

62 B 1925 The 100‑pipe: diameter 11⁹⁄₃₂ digits, circumference 35¹¹⁄₂₄ digits; capacity 81⁶⁵⁄₁₄₄ quinariae. 2 The water-men's 100‑pipe had a diameter of 12 digits, with a capacity of 92²³⁄₁₄₄ quinariae.

63 B 1925 The 120‑pipe: diameter 12¹⁷⁄₄₈ digits, circumference 38⅚ digits; capacity 97¾ quinariae. 2 The water-men's 120‑pipe had a diameter of 16 digits, with a capacity of 163¹¹⁄₁₂ quinariae — the equivalent of two 100‑pipes.

---

The Editor's Notes:

1 Following the murder of Domitian in September 96 C.E., the Senate chose Nerva as the new emperor. His reign was short: in September 97 he adopted the experienced and influential general Trajan as his heir and successor; he died on 25 January 98.

❦

2 Water commissioner, Curator aquarum. In origin, a cura was not an office in itself, but a duty or responsibility of a particular officer. As part of his vast administrative reorganizations, the Emperor Augustus created standing boards of curatores, whose members were drawn from the ranks of ex‑magistrates and whose functions were those of an imperial executive. Frontinus relates the procedures involved in creating the water commission in Chapters 99‑101 below.

❦

3 Frontinus lists his predecessors in Chapter 102 below.

❦

4 To specify a particular year, the official practice was to indicate the names of the consuls (chief magistrates, two in number) who held office. For chronological convenience, there existed a scheme of numbering years from the founding of Rome (an event that the Augustan polymath Varro placed in what we would call 753 B.C.E.).

❦

5 Aqueduct builders used types of construction appropriate for the locality and terrain. Much of the course would be comprised of underground tunnels; above ground the channels could be raised, up to five or six meters, on solid foundation-works (substructures); higher than this, they were carried along a series of arches (the highest of which, in Rome's urban aqueducts, was that which bore the combined channels of Claudia and Anio Novus: see Chapter 15 below).

❦

6 For Frontinus "the City" was probably the space encompassed by the fourteen wards (regiones established under Augustus). Inhabited areas outside this area were technically "outside the City," although for practical purposes they were sometimes recognized as being integral parts of the urban complex (see Chapters 104, 127, 129 below).

❦

7 These tanks regulated the flow of water between the channel of an aqueduct proper and the pipes which led to various uses. "Private" tanks were those from which deliveries were made to private parties (see Chapter 106 below).

❦

8 The text here is uncertain, for the crucial word meant to explain the peculiar sense of munera is apparently meaningless. The conventional view is that munera were elaborate fountains, serving a decorative purpose along with a possibly major role in the pattern of distribution.

❦

9 These were small receptacles into which water flowed without interruption, both day and night. The majority of the populace relied on these basins for their domestic needs (hence their large number and convenient locations); overflow water served to flush the City's elaborate system of drains and sewers.

❦

10 Frontinus outlines the process involved in securing such a grant in Chapters 105‑111 below.

❦

11 Prior to the introduction of the first aqueduct in 312 B.C.E. (Chapter 5 below).

❦

12 The Camenae were in origin female water-deities (later becoming Roman counterparts of the Greek Muses). They were associated with a spring located near the Porta Capena; nearby were a grove and a small shrine. From this source the Vestal Virgins drew ritual water on a daily schedule. The name is perpetuated in the modern Via Valle d. Camene, which runs along the lower edge of the Caelian.

❦

13 The manuscript reading Apollinaris is problematic. From its earliest appearance at Rome, the cult of Apollo was associated with healing. One of the first of its shrines, the Apollinare, was located outside the Porta Carmentalis; but there is no evidence for a spring in this connection. One would also expect the name of (indigenous) deities, not that of a cult or a place.

❦

14 The spring of Juturna (Lacus Iuturnae): in the Roman Forum, at the foot of the Palatine, and adjacent to the Temple of Castor and Pollux. The nymph Juturna, sister of Turnus, plays a memorable role in Book 12 of Virgil's Aeneid.

❦

15 Censors were two in number, chosen normally every five years for a term of 18 months. Among their responsibilities was that of overseeing state building projects.

❦

16 A leading statesman of his day, among the most color­ful and dramatic figures in the history of Rome.

❦

17 Called "the queen of roads," Via Appia was the principal route from Rome to south Italy and beyond.

❦

18 The gate or opening in the city-wall (that traditionally attributed to King Servius Tullius but actually built in late fourth century B.C.E.) located between the Caelian and Aventine.

❦

19 And give his name to both (this is an early example of that combination of civic pride and family ambition which motivated many building projects in the Roman Republic). In a defense of Caelius Rufus (56 B.C.E.), Cicero conjures up the venerable Appius — the better to vilify Clodia (one of his descendants) for strumpetry: "Did I bring my Water to Rome only that you should have something to wash yourself with after your impure copulations? Was the sole purpose of my Road that you should parade up and down it escorted by a crowd of other women's husbands?" [Pro Caelio 14 (34): Michael Grant translation in the Penguin series].

❦

20 The reference is probably to Gaius Licinius Lucullus, who is likely to have been the owner of this property near the end of the first century B.C.E. (when Marcus Agrippa organized the urban water system: see Chapters 9‑10, 98 below).

❦

21 The Roman mile consisted of a thousand paces (milia passuum). A "pace" was in fact a double pace, approximately 1.48 meters.

❦

22 Salinae ("salt works" or perhaps warehouses) were early commercial enterprises located on the Tiber banks at the foot of the Aventine. The name had no contemporary relevance in Frontinus' day.

❦

23 Porta Trigemina: an opening in the "Servian" city-wall, built about 190 B.C.E., slightly upstream from an earlier Porta Minucia.

❦

24 Spes Vetus: the site of an ancient shrine dedicated to Spes (personified "Hope"), called Vetus ("old") because the cult had been moved to a new temple in the third century B.C.E. This spot was the highest elevation on the east side of the City: it corresponds approximately to the present-day Piazza di Porta Maggiore.

❦

25 Horti (conventionally "gardens") are more appropriately described as large private estates. Those at Rome were sometimes open to the public, rather like modern parks. Such places bore the name of their owners (or former owners): the Horti Torquatiani had probably belonged to Torquatus Silanus, forced to suicide under Nero in 64 C.E. The Latin text originally contained the name of a second owner, thought by some scholars to have been Statilius Taurus: his property was one cause of his suicide in 53 C.E.

❦

26 Or, perhaps, Agrippa (the manuscript has only the initial letter A, followed by a blank space).

(My colorization)

❦

27 Clivus Publicius: a major street (built about 240 B.C.E.) ascending the Aventine from the Forum Holitorium ("vegetable market") — more or less the route of a modern namesake.

❦

28 Pyrrhus, the king of Epirus, had engaged the Romans in warfare for the period from 280 to 275 B.C.E. As consul in 275, Curius had himself defeated the adversary at Malventum (later called Beneventum) and celebrated a triumph.

❦

29 The text is damaged. The praetor (whose magistracy was primarily concerned with administering justice) may have merely raised the matter in the senate (as happened in a later instance: see Chapter 7); alternatively, his role may have been a procedural one in the choice of ad hoc officials.

❦

30 Modern Tivoli. This aqueduct was a considerably more ambitious project than its predecessor, the higher elevation of its source enabling it to supply more parts of the City (see Chapter 18 below).

❦

31 "On the Valerian Road" is a conjectural addition. The 20th milestone indicates a distance from Rome, but the gate (whose name is lost) may have been at Tibur. There are further uncertainties associated with the figures reported for the length of this aqueduct.

❦

32 The urban praetor dealt with lawsuits between citizens of Rome, a judicial authority which explains the mandate to reclaim public water. Marcius' other tasks had traditionally fallen to censors, and the senatorial intervention may well reflect something of an emergency which could not wait for the next censor­ship (in 142).

❦

33 An annalistic historian, writing under the Emperor Augustus.

❦

34 An enormous sum (modern equivalency would be relatively meaningless), one indication that this was the single greatest building-project Rome had to this time undertaken. Funds of this magnitude were available in booty captured from Carthage and Corinth (both cities were defeated and sacked in 146 B.C.E., the date from which Rome's mastery of the Mediterranean world was unrivalled).

❦

35 A priestly college of ten men (later increased to fifteen), whose primary duty was the custody of the Sibylline Books. These were a sacred collection of prophetic utterances, consulted when occasions demanded but only by the board of ten and only at the order of the senate. In 143 B.C.E. they are reported to have made such a consultation in connection with the consul Appius' initial defeat in a war against the Salassi.

❦

36 An epitome of Livy's history, preserved on papyrus, refers among the events of 140 B.C.E. to "Anio water" delivered "to the Capitol in opposition to the Sibyl's prophecies" (Oxy. Per. 54.188). How an apparent ban against "Anio water" could have been used to block Marcius' project to supply the Capitol with water from his new aqueduct is a mystery that may go back to Sibylline obscurity.

❦

37 The Capitoline Hill was from earliest times a religious center, but the religious objection raised by the Decemviri seems at least in part to have disguised political and/or economic motives (which can be no more than surmised).

❦

38 A statue of Marcius was erected on the Capitol behind the Temple of Jupiter. It is incidental to Frontinus' purpose that delivery to the Capitol might have been possible only by the use of a siphon. If so, it would be the earliest example of this engineering technique in Rome's water system.

❦

39 In connection with his villa at Sublaqueum (modern Subiaco): see Chapter 93 below. The older Via Valeria ran closer to the base of the mountains, hence the longer distance from road to springs.

❦

40 The precise location is unsure, in part because of the close proximity of other springs (especially those of Claudia: see Chapter 14 below). Water from these sources is still used to supply modern Rome.

❦

41 Text is damaged beyond certain repair. Tacitus describes how inviting this spring was to Nero: "He had plunged for a swim into the source of the water which Quintus Marcius had conveyed to Rome, and it was thought that, by thus immersing his person in it, he had polluted the sacred waters and the sanctity of the spot. A fit of illness which followed, convinced people of the divine displeasure" [Annals 14.22,º Church-Brodribb translation in Modern Library series].

❦

42 A different property from that mentioned in Chapters 5 and 10. Lucullus may be the same person, although this land had been in the family for some time. Tusculum is the modern Frascati.

❦

43 The source has been identified with the Sorgente Preziosa, located about 2 kilometers west of Grottaferrata. Its name derives from the warmth of the water (16‑17° C in winter, while that of nearby Julia is 10‑11° C).

❦

44 Marcus Vipsanius Agrippa (ca. 63‑12 B.C.E.), lifelong friend and apparently selfless ally of the first emperor. He had held a consul­ship in 37 B.C.E., but accepted the aedile­ship (a lower office, the duties of which were in urban administration) to win support for Octavian. His term was legendary for its munificence.

❦

45 Dio's history (48.32) records the introduction of Julia during Agrippa's praetor­ship in 40 B.C.E. This date has something to recommend it, for the name of the water suggests that Agrippa may have resuscitated a plan outlined before the death of Julius Caesar.

❦

46 In 27 B.C.E.

❦

47 The same property where Appia's source lay (Chapter 5 above).

❦

48 The principal source (still supplying modern Rome) is located near Salone, just to the left of the modern Via Collatina.

❦

49 A special type of hydraulic concrete (opus signinum) was used for this purpose, as well as for a water-tight lining on the interior of aqueduct conduits.

❦

50 In his autobiographical Res Gestae (22.4), Augustus states: "I furnished for the People a representation of a naval battle, across the Tiber, where there is now the Grove of the Caesars." This consisted of an artificial lake 1800 feet long and 1200 broad, the grand performance being part of the dedication of the Temple of Mars Ultor in 2 B.C.E. The Grove of the Caesars (Nemus Caesarum) honored Augustus' grandsons Lucius and Gaius Caesar (who died in the years 2 and 4 C.E.). The site was in Trastevere, near the present-day church of S. Cosimato.

❦

51 The modern Lake Martignano, north of Rome.

❦

52 In his Res Gestae (20.2) Augustus singles out for special mention this supplement: "I doubled the water called Marcia, introdu­cing a new spring into its channel." Although Marcia was Rome's finest water (see Chapter 91 below), there is probably an additional bit of family pride: Julius Caesar boasted descent from the Marcii Reges, and Lucius Marcius Philippus (consul in 56 B.C.E.) was married to the emperor's mother.

❦

53 Tiberius reigned from 14‑37 C.E., Gaius (Caligula) from 37‑41.

❦

54 The Porta Praenestina was an ostentatious arch was erected near the terminal point (see Chapter 20 below); this was later incorporated as a gate in the Aurelian Wall and still stands proudly (known since the tenth century as Porta Maggiore). The inscription thereupon is clearly related to the official dedication.

❦

55 Claudius' sixty-second birthday.

❦

56 Tacitus (Annals 11.13) speaks of water introduced in 47, the year in which Claudius held the censor­ship (an office he rescued from desuetude). It is generally assumed that he took up Gaius' unfinished project in 47. In any case, the appellation Claudia cannot have failed to recall that this emperor's ancestor Appius Claudius had built the first aqueduct (see Chapter 5 above).

❦

57 In close proximity to the spring of Marcia (Chapter 7 above).

❦

58 The origin of the name Curtius is unknown.

❦

59 Probably added subsequently. The name seems to mean something like "mountain water."

❦

60 The inscription on Porta Maggiore (see note 54 above) gives Claudia's conduit a total length of 45 miles.

❦

61 The mountainous region beyond Tivoli through which flows the Anio River, some 30 miles northeast of Rome.

❦

62 No remains of this intake have been discovered. As outlined by Frontinus himself (Chapter 93 below), a new intake was built upstream; normal flow of the river (to say nothing of freshets) would quickly have wiped out all traces of the earlier work.

❦

63 The inscription on Porta Maggiore (see note 54 above) gives the total length of Anio Novus as 62 miles.

❦

64 The height varied with the terrain. Frontinus' 109 (Roman) feet is equivalent to 32.3 meters. Arches north of the Cassino-Naples railway are the highest which survive; these are estimated at 27.4 meters.

❦

65 The Elder Pliny, in his Natural History (36.123), speaks with comparable emphasis: "If anyone were to give due and close attention to the abundance of waters for public use (in baths, pools, canals, households, parks, suburban estates), the distance from which the water is brought, the lofty arches, the tunnels through mountains, the bridges across valleys, he would confess that there is no sight more marvelous in the entire world." Frontinus' comparison to the Pyramids is also echoed from Pliny (Nat. Hist. 36.75): "men speak also admiringly of the Pyramids in Egypt, idle and foolish show-pieces of royal wealth."

❦

66 The Latin is uncertain, but the words "for maintenance and repair" convey what seems to be the general sense (cf. Chapter 121 below).

❦

67 The respective elevations of the channels at the point where open flow in the aqueducts gave way to distribution in closed pipes.

❦

68 See Chapters 7 and 14 above.

❦

69 Vitruvius (8.5) discusses the instruments used for levelling, and he recommends a fall of not less than ½ foot in 100 feet, or 0.5%. Marcia's channel was longer than that of Claudia, because it followed more closely the contours of terrain; the greater length inevitably resulted in loss of altitude.

❦

70 The remark best applies to the subterranean channel of Anio Vetus (early third century B.C.E.); by the time of Marcia's introduction (mid-second century) Rome was untroubled by neighborhood hostilities. The arches which carried Marcia into the City would have been vulnerable in any case — as they were when the Goths besieged Rome in the sixth century C.E. (Procopius, Gothic War 1.19.13 & 18).

❦

71 The finest example of the procedure Frontinus describes is a bridge of Anio Vetus crossing the valley of the Mola di San Gregorio. Engineers under Emperor Hadrian (117‑138) tried to compensate for the precipitous slope by putting the bridge nearly at right angles to the tunnel which followed and by making the descent as short as possible.

❦

72 Chapters 5 and 10 above.

❦

73 The terminus was about 16 meters above sea-level, but a section of its channel discovered on the Janiculum is about 71 meters above sea-level.

❦

74 Topography practically dictated the final course of all six aqueducts. They follow a prominent "finger" of higher land extending from Capannelle towards Rome, thereby maintaining (especially those on arches) altitudes which would otherwise have been impossible.

❦

75 Frontinus cites readings taken at these gauges in Chapters 67, 69, and 72 below.

❦

76 Chapter 9.

❦

77 The Latin text is uncertain, but the translation reflects both topographical and archaeological evidence.

❦

78 This gate in the "Servian" city-wall was quite near the location of modern Rome's main railway terminal.

❦

79 The property had belonged to Pallas, among the most power­ful of Claudius' freedmen, put to death under Nero (Tacitus, Annals 14.65) "for still keeping his boundless wealth by a prolonged old age."

❦

80 Remains of a channel distinctively built of tufa blocks with a circular hole in the center have been found along the course Frontinus sketches, traditionally (but not without question) attributed to this branch. The poets Juvenal (3.11) and Martial (3.47.1) both describe the gate as "dripping."

❦

81 Of all the settling-tanks, that of Anio Novus is the only one which has come to light, identified in 1884 near the Villa Bertone at Capannelle. It consisted of two chambers, both of which were found filled with calcareous pebbles (and the villa itself was constructed on an artificial mound formed by deposit which had been cleared from the tank).

❦

82 Built no doubt in the sequel to the great fire of 64 C.E., probably in connection with his vast Golden House.

❦

83 Their course can be traced by extensive remains (most of which belong to a restoration made at the beginning of the third century). The Temple of Claudius was begun shortly after his death (in October 54) by Agrippina (the widow popularly thought to have served him the fatal mushrooms); it was largely dismantled by Nero (perhaps in part to make room here for a terminal delivery-tank), but restored and completed by the Emperor Vespasian (69‑79). The site is now the garden of SS. Giovanni e Paolo.

❦

84 Remains of arches which spanned the valley between Caelian and Palatine are still standing in the Via di S. Gregorio. They can never have been high enough to carry water to the Palatine without the use of a siphon. The extension to the Aventine was probably by pipe alone, for no masonry remains have ever been reported. Water was piped from the Aventine to Trastevere across the Tiber bridges.

❦

85 "On a service-road" (in tramite) is my emendation for intra nouie, a meaningless phrase found in the manuscript. Portions of just such an official pathway have been discovered running between the parallel arcades near Porta Furba.

❦

86 Like Marcia's Herculanean Channel (Chapter 19 above), this branch may have been very old. Remains attributed to it are scanty and doubtful. It may be incautious to associate it with Agrippa's restoration (see Chapter 9 above), for Caesar's heir did not use the name Octavianus.

❦

87 Conventionally identified with the low-lying area south of the Caelian, near the later Baths of Caracalla. Neither topographical reference can be firmly located. The Asinii were an important family, with close connections to the Julio-Claudians.

❦

88 Porta Esquilina: an opening in the "Servian" city-wall, embellished in Augustan times with the Arcus Gallieni (of which the central arch still stands in the Via di S. Vito).

❦

89 Horti Luculliani: property which had belonged to Lucius Licinius Lucullus (consul in 74 B.C.E., and renowned as an epicure); it lay on the Pincian Hill, above the modern Piazza di Spagna.

❦

90 The arcade (an archway survives in the Via del Nazareno) followed a gently curving course, crossing the Via Lata (modern Via del Corso) and following the line of what is now the Via del Seminario. The Saepta ("voting precinct") was a large structure which lay just to the east of the Pantheon. The entire area formed by the bend in the Tiber was known as the Campus Martius ("field of Mars," from having been used in olden times for military training); its urban development was largely the work of Agrippa during and after his third consul­ship in 27 B.C.E..

❦

91 Chapter 5 above.

❦

92 Chapter 11 above.

❦

93 The Roman foot was approximately 29.6 cm, making the digit and the inch equivalent to 18.5 and 24.6 mm respectively.

❦

94 The "square digit" is a square 1 digit on a side, the "round digit" is a circle with a diameter of 1 digit. It emerges from Frontinus' remarks that he used the fraction ²²⁄₇ to represent π (this was the upper limit as defined by Archimedes and the figure accepted as satisfactory approximation in the works of the first-century mathematician Hero of Alexandria).

❦

95 Architect and engineer in the late Republic, and author of the De Architectura.

❦

96 Because he is primarily concerned with the calix (Chapter 36 below) and not with pipes, Frontinus ignores the fact that lead pipes were ovoid or pear-shaped rather than true circles.

❦

97 Normally a scripulum (¹⁄₂₈₈) is the smallest fraction used by the Romans.

❦

98 A circle with an area of 1 square digit.

❦

99 See Chapter 106 below.

❦

100 π times the square of ¹⁰⁄₄ equals 19.6 square digits.

❦

101 These were the official sizes decreed by Augustus (see Chapter 99 below).

❦

102 Frontinus reckons as follows: The capacity of the official 100‑pipe (81⁶⁵⁄₁₄₄) approximates that of five official 20‑pipes (16⁷⁄₂₄ × 5 = 81¹¹⁄₂₄). From five unofficial 20‑pipes they deliver 5 × 13 = 65, short of the rightful quantity by 16¹¹⁄₂₄: to this gain is added the 10¹⁷⁄₂₄ derived from the larger unofficial 100‑pipe (Chapter 32). The total gain in the case of the 100‑pipe then becomes 27⅙ quinariae. Similarly, in the case of the 120‑pipe (97¾, equivalent to six 20‑pipes) they deliver 6 × 13 = 78, short by 19¾: add the 66⅙ gained by using the unofficial pipe. Total gain in the 120‑pipe becomes 85¹¹⁄₁₂ quinariae.

❦

103 In the translation I employ familiar English units for dry measurement. The Latin cyathus was ¹⁄₁₂ of a sextarius, the sextarius ¹⁄₁₆ of a modius. There is ample evidence that precision was expected in such matters, and it was of particular importance in the distribution of free grain to the populace.

❦

104 "Accordingly" is disappointingly vague, and it is not at all clear what means of adjustment Frontinus had in mind when he speaks of "burdening" or "relieving."

❦

105 The word normally means "drinking cup." Origin of this specialized usage is obscure.

❦

106 See Chapter 113 below.

❦

107 Chapter 38 consists of a mangled repetition from Chapter 26 above, apparently in origin a reader's attempt to include even obsolete pipes in this comprehensive list.

---

Thayer's Note:

a Rodgers skips subsection 1.13.4, following Heinrich in deleting it from the Latin, presumably as a gloss.

Images with borders lead to more information. The thicker the border, the more information. (Details here.)
						next ▸
					SEE ALSO:	Roman Waterworks
UP TO:	Rodgers translation	De Aquis homepage	Frontinus homepage	Latin & Greek Texts	LacusCurtius	Home
A page or image on this site is in the public domain ONLY if its URL has a total of one *asterisk. If the URL has two **asterisks, the item is copyright someone else, and used by permission or fair use. If the URL has none the item is © Bill Thayer. See my copyright page for details and contact information.

Accessibility