Greece & Rome, Vol. 47, No. 2, October 2000

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By NEVILLE MORLEY

1. The Steam Revolution in Ancient Rome

It was never a foregone conclusion that the Roman Empire should have made any significant use of steam power. The basic principles of the steam engine were certainly known by the mid-first century A.D., as seen in the 'wind-ball' (aiolipile) described by Hero of Alexandria in his treatise on Pneumatica.1 Hero's device, in which a copper sphere was made to rotate by jets of stream when the reservoir of water underneath was heated to boiling point, clearly demonstrated that steam could serve as a source of propulsion. It was, admittedly, a very inefficient design: in modern reconstructions, either too much steam escaped through the joints or the joints had to be made so tight that friction became a serious problem. Such deficiencies were by no means insurmountable, and all the other elements necessary for the construction of a working steam engine - pistons, cylinders, an effective valve mechanism - can be found in Hero's writings or in those of his contemporaries.

However, as has often been pointed out by historians of technology, innovation is always less important than the adoption of innovation; see for example the Gallic reaping machine, described by Pliny but never, so far as we know, widely used.2 At first it seemed more than likely that Hero's device would suffer a similar fate. At the beginning of his work he characterized the inventions he described as 'some of them useful everyday applications, others quite remarkable effects', and it is prob- ably significant that he offered no suggestions as to the practical application of his windball.3 There is no evidence that anyone else at the time was interested in developing it as anything other than a toy. This attitude of indifference does not appear to be due to the fabled disdain of the ancients for the practical application of their discoveries - comments found in the writings of both Hero and Vitruvius make it quite clear that they are interested in the utility of many of the devices they describe - so much as the lack of any obvious use for a steam engine.4

Such a statement may seem strange to us, familiar as we are with the

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dramatic impact of steam power on the economy and society of nineteenth-century Britain and America; its usefulness seems over- whelmingly obvious.5 To understand the attitude of the ancients, it is important for us to be wary of our assumptions about technological development; above all, of the idea that people will eagerly adopt innovations with the aim of saving time and labour in the production process. Such an assumption is natural in a capitalist economy, where labour is commoditized and the capitalist's profits depend on as much work as possible being carried out within a given time by each labourer. In the ancient world, however, free wage labour was little used (except for casual labour at the harvest); peasants relied on their own and their family's labour while the rich tended to rely on various forms of dependent labour (slave, tenants, serfs), and so neither would have thought of labour in terms of a commodity, as something that needed to be saved.6 In other words, they had no obvious motive for adopting or developing a machine that did the same work as a man or an animal, only slightly faster. The mere existence of an innovation (which we, with the benefit of hindsight, know to have the potential to transform society) does not guarantee that it will be widely adopted if it is not 'appropriate' to, or seen to be beneficial by, the society in question.7 The ancients, particularly the Romans, were always willing to innovate or adopt the innovations of others when it suited their purposes; for example, in the development of urban water supplies, in agriculture, and in military affairs.8 Their initial failure to adopt steam power is not a sign of their ignorance or primitiveness, but simply a clear indication that their values and attitudes differed markedly from our own.9

The employment of steam engines even to a limited extent in certain areas of agriculture and industry was a very late development, long after the engines had been tried and tested in the service of the emperor. As one might be expected, the chief motive for their initial adoption was essentially political. Since the time of Augustus, the emperors had recognized the necessity of safeguarding the grain supply of the city of Rome; the consequences of failing to do so can be seen in the attacks made by angry mobs in the forum on the then Octavian in 40 B.C. and on Claudius in A.D. 51.10 In response, Augustus had instituted the office of the praefectus annonae and added grain-rich Egypt to the empire; Claudius offered concessions to suppliers to persuade them to supply the city, and also started work on construction of a proper harbour at Ostia (up to this date, ships had had to moor outside the sand

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bar at the mouth of the Tiber while transferring their cargoes to smaller boats for the journey to the city).

These measures certainly improved the situation, but there remained a serious bottleneck in the system of supply: the river Tiber. Rickman has estimated that the barges necessary to transport the city's grain supplies (to say nothing of the vast quantities of other goods) would have been nose-to-tail along the river between Ostia and Rome through- out the entire year.11 The slightest hitch might mean that grain piled up at the port while Rome suffered price rises and even shortages. Nero's proposal to build an additional canal between the city and the sea, which would, according to Suetonius, have allowed ships to sail straight up to Rome, is a clear indication of continuing problems at this stage of the supply network (and not, as historians have tended to assert, simply another example of his megalomania).12

Nero's successors were more concerned with replenishing the treas- ury, and probably also wary of associating themselves with a building project tainted by Nero's involvement; they concentrated on reconstruc- tion of damaged areas of the city, on temples and on the new amphitheatre on the site of Nero's Golden House.13 Under Nerva, however, who was described by Frontinus as 'an emperor of whom I am at a loss to say whether he devotes more industry or love to the state', we find a return to large-scale public building projects relating to the city's supplies.14 Nerva focused both on the system of aqueducts (with extensive renovations, new construction and a thorough overhaul of the administration) and also on the food supply, with the construction of state granaries and improvements to the city's transport links with the coast.15 Nero's canal project was still not revived; instead Nerva sought to supplement the existing road and river transport with an entirely new form, based on steam power. A track was built along the side of the Tiber, consisting of a stone pathway into which parallel grooves were cut to guide the wheels of the wagons; the obvious model for this arrangement being the Diolkos 'railway' in Greece, originally con- structed around the sixth century B.C., which was used to transport ships across the Corinth isthmus.16

Little is known of Nerva's original engine; visual representations of the 'railway' (for example, the famous mosaic from the collegium of the machinarii in the Piazza delle Corporazioni at Ostia) all date from the middle decades of the second century or later.'7 It is possible that it was at first used to pull barges up the Tiber, since archaeological investiga- tion has shown that the track followed the line of the river closely even

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when a more direct route existed. Soon, however, the engines were being used to draw wagons of grain and other goods; clearly they were more effective as a supplement to river transport, increasing the total volume of goods that could be carried up to the city and, unlike the Tiber barges, free from the seasonal problems of floods and low water levels.18 The fact that the engines were employed in this way also seems to imply that they were both faster than ox-drawn carts and able to haul a similar or larger load.19 This was certainly the case with later models; mosaics from Ostia show lines of four or five heavily-laden wagons being drawn along, and Pliny describes in a letter how the engine on the opposite bank almost kept pace with his horse as he travelled to his villa at Laurentum.20 There is of course no reason to believe that the steam engine was necessarily cheaper than existing forms of transport; more than likely the railway was a typical imperial project in which the costs - of developing the engine, of manufacturing and maintaining it, and of collecting the huge quantities of wood needed to fuel its boiler - were far less important than obtaining the desired end of protecting the food supply of the city.

A second track between Rome and Ostia was constructed under Trajan, always an emperor to make the most of his predecessor's work.21 Trajan also started to build railways elsewhere in the empire, and this almost certainly explains why the steam engines, which became known as machinae Traianae, are associated in the popular mind with him rather than Nerva. Once again, the engines were originally introduced as a way or circumventing transport bottlenecks, this time in the supply lines of the army; first of all to link the Rhine to the Rhone and the Danube, and then extending into newly conquered regions.22 It is difficult to believe that these railways were cost-effective from a strictly economic point of view, but, as with the city of Rome, the need to keep the army well supplied far outweighed any economic considerations.23 By the time of Trajan's later wars against Parthia, railways followed rapidly in the footsteps of the advancing armies, and this surely enabled Rome to maintain its hold on the newly created provinces of Armenia, Mesopo- tamia, and Assyria in the face of Parthian counter-attacks.24 Likewise, the railways linking the Rhine to the Weser and the Elbe consolidated the conquest of further areas of Germania under the Antonines. It was only a matter of time before the engines were used for transporting troops as well as supplies, enabling reinforcements to be moved rapidly to problem areas and greatly reducing the total number of troops necessary to defend the frontiers effectively.25

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Emperors still faced some problems on the frontiers; less from barbarian or Parthian enemies than from their own generals, who might take advantage of weakness at the centre to launch a bid for power. This doubtless explains why no emperor took what to us might seem the obvious step of connecting the different railway tracks into a more integrated system, linking the provinces to Italy; the advantages of improved communication and more efficient movement of goods were far outweighed by the risk of a usurper being able to launch an attack on the capital without warning. On the other hand, by ensuring that the troops were regularly supplied, paid, and relieved, and thus less likely to revolt, the steam engine may perhaps be given some credit for the notable political stability of the second and third centuries A.D. While the frontier pushed slowly forward, the rest of the empire enjoyed peace and stability (not to mention the benefits of a continued flow of booty and revenues), and the newly conquered regions of Germania followed Gaul and Britain on the path of 'Romanization', assimilation under the globalizing cultural hegemony of the Mediterranean.

The arrival of steam power made only a slight difference to other aspects of life in the empire. Steam engines were rarely employed in industry, except for a few state-owned milling complexes. The vast majority of the population were in no position to afford such machines, which would anyway have been quite redundant in a small farm or workshop; the wealthy were quite content with the labour of their slaves. Land remained the fundamental source of wealth; the advent of steam power simply reinforced this, as those who had the money to invest bought up large tracts of forest to take advantage of the insatiable appetite of Trajan's engines for fuel. A few previously under-developed regions of Italy and Gaul, and in particular the newly conquered territories of Germania, saw a flurry of activity as a result.

With the inevitable exception of the technically-minded Frontinus, whose treatise on railway management (based on his experiences in organizing the Ostia-Rome line) is unfortunately lost, the upper-class writers of the time more or less ignored the whole development. They made an exception only on the extremely rare occasions when one of the railway managers (who were often imperial freedmen, to judge from the epigraphic record) amassed sufficient wealth from state contracts to buy his way into the nobility - naturally abandoning at once all interest in railways and other sorts of trade, and investing in land. It is in this context that we find remarks like those of Juvenal about the successful freedman Fumosus, who has 'scarcely pumiced away the layers of

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charcoal and soot' before arriving at dinner, where he can talk of nothing but the 'contraptions of Archimedes'.26 One or two of the more adventurous landowners invested in private railways as a means of transporting the produce of their villas to market,27 but for the most part only the state had either the resources or the motivation to invest in these expensive, noisy and rather vulgar machines, and their construc- tion and maintenance remained largely in the hands of freedmen.

What if Rome had never adopted the steam engine? What if it had remained simply a minor curiosity in the history of science and technology that the ancients developed the principles of steam power but never put them into practice? As discussed above, such a turn of events at one point seemed more than likely. The adoption of the steam engine depended on the whim of a particular emperor, who might easily have chosen another method (reviving Nero's plans for a canal, perhaps, or further development of the port facilities at Ostia) to try to solve the problem of Rome's food supply. No-one other than the emperor was likely to wish to invest the necessary money in such an eccentric enterprise. For an indication of how else things might have turned out, we might compare Nerva's willingness to adopt innovations to the negative response of Vespasian when he was offered a device designed to haul columns up to the Capitol.28

How much difference would this have made? We might consider this in the light of the famous study by the economic historian Robert Fogel, examining the role of railroads in the development of the United States in the nineteenth century.29 Fogel approached this question by using a 'counterfactual' argument, constructing a model of American development if it had been based on canals and river transport rather than railroads. He concluded from this model that US GNP in 1890 would have been more or less the same, while the total cultivated area would be smaller but more intensively exploited. We might suggest something similar for Rome. The empire's frontiers would be less extensive, since its expansion would have been restricted not by natural boundaries or by strategic considerations but by the length of its supply lines.30 Otherwise we might expect few dramatic differences; just as American capitalists would have found alternative means to transport their goods to market, so the Roman state would have got by with traditional methods.

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2. Technology and History

In recent years there has been something of a flurry of interest in 'counterfactual' approaches to history (or 'virtual history', to quote the self-consciously neoteric title of the most recent collection on the subject): that is, the examination of 'what if?' questions, as in 'what if Hitler had invaded Britain?' or 'what if Constantine had remained a pagan?'. In the past, such questions have generally been excluded from the remit of 'proper' history; perhaps above all because they blur the distinction between history and fiction, emphasizing the role of the historian's imagination in the process of interpretation and thus suggest- ing that every history is to some extent an imaginative construct.31 Critics of the 'what if' approach also point to the dangers of reliance on hindsight, excessively reductive explanations and anachronistic assumptions, all of which can indeed be found in most of the attempts made so far at writing counterfactual history.32 Nevertheless, counter- factuals are implicit in any discussion of causation:

The force of an explanation turns on the counterfactual which it implies. If such-and- such a cause or combination of causes had not been present, we imply, or if such-and- such an action or series of actions had not been taken, things would have been different. If we do not believe they would have been, we should not give the causes or actions in question the importance that we do.33

A counterfactual approach to history compels us to make these assump- tions about causation explicit, by focusing on the possible existence of other plausible outcomes.

Almost every published attempt at 'virtual history' has focused on traditional military and political problems: what if Alexander had lived longer, or Charles I avoided civil war, or Britain kept out of WW1, or Germany defeated the Soviet Union in 1941, or JFK escaped assassina- tion?34 There seem to be a number of reasons for this tendency. In the first place, this kind of history is still the main interest of many historians, and is certainly more popular amongst the wider public than economic or social history.35 Secondly, it is easier to demonstrate that other possibilities existed in the past (and therefore to justify an interest in counterfactual history) when the focus is on an individual decision; both because the individual clearly could have changed his or her mind, and also because contemporary evidence often confirms that other possibilities were considered or even expected. In the Virtual

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History collection this latter fact has been elevated to a guiding principle: 'We should consider as plausible or probable only those alternatives which we can show on the basis of contemporary evidence that contemporaries actually considered' - which would clearly exclude social and economic developments of which contemporaries were largely or entirely un- aware.36 Thirdly, there is often an implicit or explicit opposition to the perceived determinism of much economic and social history, above all that produced by Marxists and by those inspired by the French historian Ferand Braudel, with their emphasis on the structures that condition people's lives. Counterfactual political history, with its em- phasis on contingency and the range of alternative possibilities open to its actors, is presented as a means of defending free will against soulless (left-wing) determinism.37

Having offered a counterfactual history of Roman technological development, proposing a course of events which no contemporary ever contemplated for a moment, I do feel that I should offer some response to these points. The first is simply a matter of personal preference.38 The second shows a remarkable excess of caution, as if we can never take advantage of hindsight or our more advanced knowledge (of economics, sociology, medicine etc.) to identify possibil- ities to which contemporaries were completely oblivious. The third point, leaving aside its ideological slant, is a misrepresentation of most economic and social history, and even of the two writers who are singled out for particular censure. Both Marx and Braudel accepted that the structures they identified (economic, social, environmental, mental etc.) do not absolutely determine human behaviour but rather (in Braudel's phrase) set 'the limits of the possible' for human action.39 Moreover, both argued quite explicitly that such structures change, admittedly over longer periods of time and in a more complicated manner than one individual simply making a different decision. The free will question thus becomes irrelevant; what matters is the need to broaden counter- factual history by considering the consequences of alternative lines of development not only at the level of individual decisions but also in economic and social trends and even in the environment. As with other counterfactual history, this offers a way of examining the implicit assumptions of any explanation; for example, if climate is seen to be the main shaper of development, how might things have changed if average temperatures in Europe had been different, with all the likely consequences for agriculture, travel, the incidence of disease and so forth?40

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The history of ancient technology as it has generally been written does indeed depend on an implicit 'what if' question, an assumed alternative line of development. Ancient technology is implicitly or explicitly compared with medieval and later developments; as a result it is seen to be stagnant, underdeveloped, lacking key innovations.41 Most histor- ians have then taken it as read that they need to explain this failure to develop; the range of explanations provided includes the widespread use of slave labour, the non-practical nature of ancient science, the ancient conception of the relationship between man and the natural world, the low status of manufacturing, a shortage of capital, the low level of demand for goods and so forth.42 Underlying such arguments is the assumption that if these impediments had not existed then antiquity would have developed along much the same lines as late medieval and early modern Europe, experiencing an industrial revolution and the triumph of economically rational, capitalist modes of thought.43

The anachronistic, Eurocentric assumptions of this approach to the study of ancient technology have been extensively and persuasively criticized in recent articles by Kevin Greene.44 This paper is intended to offer a complementary critique by taking up the counterfactual implicit in the argument. I would suggest that it was not inconceivable that the Romans might have adopted steam power; the basic principles were known, they were certainly prepared to adopt innovations when it suited them, and a suitable application for such technology did exist. However, as my 'history' is intended to suggest, we cannot then assume that the course of development of a steam-powered Roman Empire is fixed or obvious. We cannot assume that the Roman empire was simply awaiting the development of more advanced technology to become a modern capitalist society, or that technology inevitably has this kind of modern- izing impact on any society into which it is introduced.

This kind of technological determinism is implicit in much historical writing (and in most science fiction); in essence it takes up the argument of the early Marx that 'the hand mill will give you a society with the feudal lord, the steam mill a society with the industrial capitalist'.45 My piece of imaginary history assumes on the contrary that technology is subordinate to other social and economic structures, which determine how it will be used. Everything we know about the Roman Empire makes it extremely improbable that it would suddenly industrialize, or support the emergence of a new class of capitalists or a 'capitalist spirit' so alien to traditional attitudes. The adoption of steam power might lead to a transformation of society, if particular groups (above all the political

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elite) were to act in certain ways, but it might equally help to perpetuate the existing social order - as indeed we find today.46 Rather than assimilating Rome to our own society, the historian's aim should be to imagine a sophisticated and even technologically advanced society which was not organized along modern capitalist lines. As with the best science fiction, such speculation may help us consider the nature of change and development, offering a commentary on the present as well as the past.47 What might it tell us about our faith in and fear of technology, our sense that it is the machines, rather than the people who use them in particular ways and the social structures which condition their use, that create the condition of (post)modernity?

Conclusion: The Fall of the Roman Empire

It is of course possible that I might have been writing this not in 1999 but some time in the second century of the Valerian dynasty, the latest set of true heirs to the empire of Augustus; or, counting from the traditional date of the foundation of Rome, in 2752. After all, Chinese civilization survived for a similar length of time, weathering regular changes of dynasty with comparatively little disruption, until it was confronted in the late nineteenth century with what lain Banks has termed an 'out of context problem'.48 A steam-powered Roman Empire might have expanded across the whole of Asia, assimilating or crushing not only the nomadic barbarians whom the Romans had once naively seen as a threat to their security, but also their more dangerous rivals in Persia, India, and China.

On the other hand, with the exception of China, it is difficult to think of examples of civilizations which have survived for anything like this period of time. Modern capitalist society, at barely a couple of centuries, has a long way to go to prove its stability and long-term viability. As for China, it clearly differed from Rome in many significant ways; above all in its sophisticated system of administration, which was not seriously disturbed by changes at the head of the empire.49 There seems to be no obvious reason why steam power at Rome should have improved the empire's record of problems with the succession and subsequent civil war; no reason why steam power should have led to a more equal division of property, or reduced the problems of its limited tax base and ineffective tax system and hence its inflexibility in the face of unexpected disasters. Of all the reasons put forward for the eventual fall of the

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Roman Empire - political crisis, corruption, economic problems, environmental change, barbarian invasions, the problem of holding together such a vast territory - steam power might have made a significant difference only to the last two. Perhaps its adoption might even have hastened the empire's decline, increasing environmental degradation through pollution and deforestation and bringing about a preindustrial energy crisis.50

In the eighteenth and nineteenth centuries, many writers looked to the Roman Empire for indications of the likely fate of modern civilization, trying to heed its awful warning about the corrupting effects of luxury, decadence, and unbridled self-interest.51 Today, we are more aware of the differences between past and present, above all in material terms. We might now look to Rome to see how else things might have been - for example, it offers a reminder that capitalism is not the only way of organizing a society - and perhaps also how else things might be.52 Like science fiction, all history, imaginary or not, is in the end concerned above all with the present.53

NOTES

1. Hero, Pneumatica 2.11. There is an English translation by B. Woodcraft (London, 1851); the passage is also reproduced in J. W. Humphrey, J. P. Oleson and A. N. Sherwood, Greek and Roman Technology: a Sourcebook (London and New York, 1998), 28. Hero's device is discussed by, among others, A. G. Drachmann, The Mechanical Technology of Greek and Roman Antiquity (Copenhagen, 1963), 206; J. G. Landels, Engineering in the Ancient World (London, 1978), 28-33; K. D. White, Greek and Roman Technology (London, 1984), 195; P. James and N. Thorpe, Ancient Inventions (London, 1995), 131-5.

2. Key works on the nature and limitations of ancient technology include M. I. Finley, 'Technical innovation and economic progress in the ancient world', Economic History Review 18 (1965), 29- 45; H. W. Pleket, 'Technology and society in the Graeco-Roman world', Acta Historiae Neerlandica 2 (1967), 1-25; D. W. Reece, 'The technological weakness of the ancient world', G&R 16 (1969), 32-47; K. D. White, 'Technology and Industry in the Roman empire', Acta Classica 2 (1959), 78- 89, and 'Technology in classical antiquity: some problems', Museum Africum 5 (1976), 23-35. The most up-to-date discussions, including criticism of the assumptions of many earlier histories of technology, are found in a series of articles by Kevin Greene: 'Perspectives on Roman technology', Oxford Journal of Archaeology 9 (1990), 209-19; 'The study of Roman technology: some theoretical considerations', in E. Scott, ed., Theoretical Roman Archaeology: first conference proceedings (Alder- shot, 1993), 39-47; and 'Technology and innovation in context: the Roman background to medieval and later developments', Journal of Roman Archaeology 7 (1994), 22-33. Pliny describes the reaping machine in HN 18.296; it is discussed by Pleket, 'Technology and society', 15, and K. D. White, Roman Farming (London 1970), 448-9.

3. Quoted by Landels, Engineering (n. 1), 29. 4. The idea that ancient science was disdainful of practical applications is particularly emphas-

ized by Finley, 'Technical innovation', 32-3. Book 3 of Hero's Pneumatica is generally concerned with devices which have practical utility; see White, Greek and Roman Technology (n. 1), 180-3. Cf. Vitruvius 9, preface 6, on the application of Pythagoras' mathematical principles, and 10.1.4: 'Now all machinery is generated by Nature, and the revolution of the universe guides and controls . .. Since then our fathers had observed this to be so, they took precedents from Nature; imitating them,

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and led on by what is divine, they developed the comforts of life by their interventions. And so, they rendered some things more convenient, by machines and their revolutions, and other things by handy implements. Thus what they perceived useful in practice they caused to be advanced by their methods, step by step, through studies, crafts and customs.'

5. See for example P. Hudson, The Industrial Revolution (London, 1992) and E. A. Wrigley, Continuity, Change and Chance: the Character of the Industrial Revolution (Cambridge, 1988).

6. Greene, 'Study of Roman technology' (n. 2), 41. On labour, see P. Garnsey, ed., Non-Slave Labour in the Greco-Roman World (Cambridge, 1980).

7. Similar points have been made about the introduction of Western technology into non- Western, 'developing' countries. See C. A. Alvares, Homo Faber: Technology and Culture in India, China and the West, 1500-1972 (Bombay, 1979) and G. Basalla, The Evolution of Technology (Cambridge, 1988), 207-18.

8. White, Greek and Roman Technology (n. 1), offers the most accessible general survey. On water supply, see Frontinus, De Aquis, and A. T. Hodge, Roman Aqueducts and Water Supply (London, 1992). On agricultural innovation, see N. Morley, Metropolis and Hinterland: the City of Rome and the Italian Economy (Cambridge, 1996), 115-21. On military machines, see Vitruvius Book 10.

9. We might compare discussions of whether the ancients possessed 'economic rationality': A. Carandini, 'Columella's vineyard and the rationality of the Roman economy', Opus 2 (1983), 177-204; M. I. Finley, The Ancient Economy (London, 2nd edn 1985), 108-22; G. Mickwitz, 'Economic rationalism in Graeco-Roman agriculture', English Historical Review 52 (1937), 577-89; P. W. de Neeve, 'The price of land in Roman Italy and the problem of economic rationalism', Opus 4 (1985), 77-109; D. W. Rathbone, Economic Rationalism and Rural Society in Third-Century A.D. Egypt (Cambridge, 1991).

10. On grain supply, see P. Garnsey, Famine and Food Supply in the Graeco-Roman World (Cambridge, 1988), 167-243. For more on the relationship between the emperors and the people of Rome, see P. Veyne, Bread and Circuses: Historical Sociology and Political Pluralism (trans. B. Pearce, London, 1990), 292-482, and Zvi Yavetz, Plebs and Princeps (Oxford, 1969), esp. 9-37.

11. G. Rickman, 'Problems of transport and development of ports', in A. Giovannini, ed., Nourrir la Plebe: actes du colloque . .. en hommage a Denis van Berchem (Basel, 1991), 103-15.

12. Suetonius, Nero 16. For a positive evaluation of this proposal, see M. Griffin, Nero: the End of a Dynasty (London, 1984), 130.

13. Suetonius, Vespasian 16 on his parsimony and 8-9 on his building projects. B. W. Jones, The Emperor Titus (London and Sydney, 1984), 143-6.

14. Frontinus, De Aquis 1. 15. De Aquis 1, 87-8; B. W. Henderson, Five Roman Emperors (Cambridge, 1927), 169-74. 16. On the Diolkos 'railway', see Landels, Engineering (n. 1), 182-3. 17. On the Piazza, see R. Meiggs, roman Ostia (Oxford, 2nd edn 1973), 283-8 and PI. XXIII-

XXV. 18. On problems with using Italian rivers for transport, see D. S. Walker, A Geography of Italy

(London, 2nd edn 1967), 270. Morley, Metropolis and Hinterland (n. 8), 104-6, briefly discusses some of the laws aimed at maintaining the level of water in rivers used for transport.

19. Comparative material on the advantages and disadvantages of oxen: D. R. Ringrose, Transportation and Economic Stagnation in Spain, 1750-1850 (Duke, 1970); A. C. Leighton, Transport and Communication in Early Medieval Europe, A.D. 500-1100 (Newton Abbot, 1972); J. Langdon, 'The economics of horses and oxen in medieval England', Agricultural History Review 30 (1982), 31-40.

20. Of course, that engine would have been lightly laden as it was heading away from the city. On Pliny's Laurentum villa, see Ep. 2.17.

21. J. Bennett, Trajan: Optimus Princeps (London and New York, 1997), esp. 138-60 on building projects and 85-103 on the Dacian Wars.

22. On the Rhine-Danube corridor and its strategic importance, see C. R. Whittaker, The Frontiers of the Roman Empire: a Social and Economic Study (Baltimore and London, 1994), esp. 38- 9, 43.

23. We might note the tendency, seen from archaeological data, to transport pottery thousands of miles from a state-owned pottery, rather than manufacturing it locally: Whittaker, Frontiers (n. 22), 101-4.

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24. On Trajan's Parthian campaigns, see Bennett, Trajan (n. 21), 183-204. 25. On frontier defence, especially the idea of 'defence in depth' using a mobile strike force, see

E. N. Luttwak, The Grand Strategy of the Roman Empire (Baltimore, 1976); contrast J. C. Mann, 'Power, force and the frontiers of the empire', JRS 69 (1979), 175-83, who disputes the idea that this should be seen as a coherent military strategy rather than a short-term reaction to circum- stances.

26. Since other indications suggest that the poem is supposed to be set in time of Domitian, these remarks are, to say the least, rather anachronistic; see G. Highet, Juvenal the Satirist (Oxford, 1954), 9-11, on the dating of the poems. Similar attacks on successful ex-slaves: 1.22-39, 1.102-20.

27. As early as Cato, the Roman agronomists had recommended choosing a villa with good transport links (Agr. 1.3-5; Varro, RR 1.16.1-3, 6). Some landowners are known to have built private roads (T. W. Potter, The Changing Landscape of South Etruria [London, 1979], 108) and quays (see Livy 40.51.2), so for a few a small local railway was a natural step. Of course, it is debatable whether such railways were constructed purely for productive purposes or whether they were also designed for pleasure and as a means of ostentatious display, an attitude to villa management which is exemplified in Varro's discussions of aviaries and fishponds (RR 1.4.1-2, 3.3.6, 3.4.3; cf. Morley, Metropolis and Hinterland (n. 8), 90-5.

28. Suetonius, Vespasian 18. 29. R. W. Fogel, Railways and American Economic Growth: Essays in Interpretative Economic

History (Baltimore, 1964). Discussed by Niall Ferguson, 'Virtual History: towards a 'chaotic' theory of the past', in N. Ferguson, ed., Virtual History: Alternatives and Counterfactuals (London, 1997), 17-18.

30. Whittaker, Frontiers, 85-97, on the importance of supply lines in determining the location of frontiers.

31. Ferguson, 'Virtual history' (n. 29), discuses a range of reasons for hostility towards such questions. On the relationship between history and fiction, see P. Veyne, On History (Manchester, 1984) and N. Morley, Writing Ancient History (London, 1999).

32. The most sophisticated attempt so far, both in theoretical underpinning and in realization, is Geoffrey Hawthorn, Plausible Worlds: Possibility and Understanding in History and the Social Sciences (Cambridge, 1991); heavily (but to my mind unfairly) criticized by Ferguson (n. 29), 18-19.

33. Hawthorn, Plausible Worlds (n. 32), 14. 34. The Virtual History collection offers alternatives to the English Civil War, the American

Revolution, the partition of Ireland, the defeat of Germany in both World Wars, the Cold War, the assassination of JFK and the collapse of Communism. Similar subjects are covered by J. C. Squire, ed., If It Happened Otherwise: Lapses into Imaginary History (London, New York, and Toronto, 1932); D. Snowman, ed., If I Had Been . . . Ten Historical Fantasies (London, 1979) and J. M. Merriman, ed., For Want of a Horse: Chance and Humor in History (Lexington, 1984). See also A. J. Toynbee, 'If Alexander the Great had lived on', in Toynbee, ed., Some Problems in Greek History (Oxford, 1969). One of the merits of Hawthorn's Plausible Worlds is that it explores economic and social history (what if plague had not been a serious cause of mortality in early modern Europe?) and art history.

35. All the works listed in n. 29, with the exception of Hawthorn's, were clearly intended, and certainly marketed, for a largely non-academic audience.

36. The quote is from Ferguson, 'Virtual history' (n. 29), 86; his italics. 37. This ideological tendency is most explicit in Ferguson, 'Virtual history' (n. 29), esp. 52-64.

'The determinism of the nineteenth century was not, as might have been expected, discredited by the horrors perpetrated in its name after 1917. That Marxism was able to retain its credibility was due mainly to the widespread belief that National Socialism was its polar opposite, rather than merely a near relative which had substituted Volk for class' (52-3).

38. Except in so far as a preference for traditional political history is ideologically motivated; see previous note.

39. On Marx, see E. M. Wood, Democracy Against Capitalism: Renewing Historical Materialism (Cambridge, 1995), 108-45, and R. Brenner, 'Bourgeois revolution and transition to capitalism', in A. L. Beier et al., eds., The First Modern Society (Cambridge, 1989); contra e.g. G. A. Cohen, Karl Marx's Theory of History: a Defence (Princeton, 1978). Braudel's own views are clear, in The Mediterranean and the Mediterranean World in the Age of Philip II (London, 1972), The Structures of

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Everyday Life: the Limits of the Possible (London, 1981) and 'History and the social sciences: the longue duree', in On History (Chicago, 1980), 25-54. Discussed by P. Burke, The French Historical Revolution: the Annales School 1929-89 (Cambridge, 1990), 32-53.

40. A question whose contemporary relevance is quite as obvious as the old 'what if Hitler had won?'.

41. One obvious example is the contrast between Roman agriculture and the supposed 'medieval agricultural revolution': propounded by L. White Jnr, Medieval Technology and Social Change (Oxford, 1962) and Georges Duby, Rural Economy and Country Life in the Medieval West (Columbia, 1976); disputed by H. W. Pleket, 'Agriculture in the Roman Empire in comparative perspective', in H. Sancisi-Weerdenburg et al., eds., De Agricultura: in memoriam Pieter Willem de Neeve (Amsterdam, 1993), 317-42, and Morley, Metropolis and Hinterland (n. 8), 118-20.

42. See the articles cited in n. 2, particularly those by Finley and Reece. 43. The roots of this way of thinking lie deep. At the beginning of this century Max Weber, a

major influence on Finley, was analysing the Roman Empire in terms of the 'impediments' it presented to the full development of capitalism; see The Agrarian Sociology of Ancient Civilizations (trans. R. I. Frank; London, 1976), 65-6, 358-65. The same assumptions also permeate 'developmental economics', where non-Western countries are encouraged (or compelled) to try to develop according to the blueprint laid down by the European experience; see P. Hill, Development Economics on Trial (Cambridge, 1986).

44. See n. 2. 45. 'The Poverty of Philosophy', in K. Marx & F. Engels, Collected Works Vol. VI (London,

1976), 166. As noted above (n. 34), in his mature works (Grundrisse and Capital) Marx abandons this crude determinism.

46. For all the claims about the liberating power of technology like the Internet, economic power and political influence are if anything even more concentrated than before in the hands of multinational corporations. See e.g. T. Jordan, Cyberpower: the Culture and Politics of Cyberspace and the Internet (London, 1991) and B. D. Loader et al., The Governance of Cyberspace: Politics, Technology and Global Restructuring (London, 1997).

47. J. G. Ballard, A User's Guide to the Millennium: Essays and Reviews (London, 1996), 14: 'S-f has been one of the few forms of modem fiction explicitly concerned with change - social, technological and environmental - and certainly the only fiction to invent society's myths, dreams and utopias.'

48. In Excession (London, 1997). 49. Roman and Chinese systems of administration are contrasted by Keith Hopkins, 'Taxes and

trade in the Roman Empire', JRS 70 (1980), 120-1. 50. On ancient environmental problems, see J. D. Hughes, Pan's Travail: Environmental

Problems of the Ancient Greeks and Romans (Baltimore and London, 1994), esp. 112-29 on industrial pollution and 181-99 on the environmental causes of the collapse of classical civilization.

51. See e.g. F. M. Turner, Contesting Cultural Authority: Essays in Victorian Intellectual Life (Cambridge, 1993), 231-61, and N. Vance, The Victorians and Ancient Rome (Oxford, 1997), 247- 68. Of course, the twentieth century has also produced examples of this approach: see M. I. Rostovtzeff, Social and Economic History of the Roman Empire (Oxford, 2nd edn 1957), 536-8, or F. W. Walbank, The Awful Revolution: the Decline of the Roman Empire in the West (Liverpool, 1969), 114.

52. Contra F. Fukuyama, The End of History and the Last Man (New York, 1992), who argued that liberal-democratic capitalism has now conclusively 'won' the ideological struggle and is therefore recognized universally as the best possible way of organizing society.

53. The original version of this paper was delivered at the Classical Association Conference in Liverpool in April 1999. I am very grateful to everyone who made comments and suggestions on that occasion, especially Stephen Clark, Ahuvia Kahane, and Nick Lowe; I also wish to thank Geraint Osborn and Anne Morley.

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Issue Table of ContentsGreece & Rome, Second Series, Vol. 47, No. 2 (Oct., 2000), pp. 149-296Volume Information [pp. 293 - 296]Front MatterThe Significance of Stage Properties in Euripides' 'Electra' [pp. 149 - 168]The Audiences of New Comedy [pp. 169 - 171]The Nurturing Male: Bravery and Bedside Manners in Isocrates' 'Aegineticus' (19.24-9) [pp. 172 - 185]'Half-Burnt on an Emergency Pyre': Roman Cremations Which Went Wrong [pp. 186 - 196]Trajan's Engines [pp. 197 - 210]'To Make a New Thermopylae': Hellenism, Greek Liberation, and the Battle of Thermopylae [pp. 211 - 230]Reviewsuntitled [pp. 231 - 232]untitled [pp. 232 - 235]untitled [pp. 235 - 236]

Subject Reviews [pp. 237 - 273]Books Received [pp. 274 - 287]Back Matter [pp. 288 - 291]