A History of the World in 12 Maps

by Jerry Brotton

  But, as we saw at the beginning of this chapter, the map was not banned, but nationalized (or confiscated, depending on your political sympathies) by the National Convention in September 1793. Nationalization meant that the map was completely withdrawn from public circulation, its plates and published sheets confiscated by the Dépôt de la Guerre in the interests of the new nation. In December 1793, as the ‘Reign of Terror’ swept Paris, the company’s shareholders were called to what would be its last general meeting. Cassini IV and his loyal assistant Louis Capitaine waited in vain. Finally, a solitary shareholder arrived. ‘Gentlemen, believe me,’ he announced, ‘you may do as you wish, we all have plenty of other things to think of than maps. For myself, I shall bid you good day and find hiding where I can.’50 The net was closing around Cassini: already stripped of his membership of the Académie (which was subsequently disbanded) as well as the directorship of the Observatory, he was thrown into prison in February 1794. Condemned by his students, he narrowly avoided the guillotine, a fate which befell his unfortunate cousin and fellow prisoner, Mlle de Forceville, as Cassini looked on helplessly.

  As the Terror subsided in the summer of 1794, Cassini was released from prison, but he was a broken man. He turned his back on science, railing against the revolutionary reforms as ‘overturning everything, of changing everything without need, and for the sole pleasure of destruction’.51 He flirted with requests to join several academic societies, and supported Capitaine’s attempts to compensate the shareholders of the Société de la Carte de France for their losses. When Philippe Jacotin, the head of the topographical department of the Dépôt de la Guerre, was delegated to assess what the state owed the shareholders (including Cassini), he simply calculated the changing metal value of the engraved copper map plates over twenty years, deducting the costs of maintaining them over the same period. He arrived at a figure of 3,000 new French francs (roughly equivalent to the old livre) for each share. Cassini was predictably outraged. ‘It seems to me’, he fulminated, ‘that it isn’t some colonel, the head of the topographic office, that one should turn to for such an expert opinion, but rather to a boiler-maker, who understands better than anyone the value of old copper.’52 Fifty years of scientific labour by father and son were now valued according to the price of the copper used to make their map engravings. It was a miserable end to a glorious project. Disillusioned and scorned, Jean-Dominique retired to the family home in Thury, where he died in 1845, aged 97.

  Technically speaking, the general map of France was never finished. Following its nationalization, everything related to the survey and its maps was transferred to the Dépôt de la Guerre. This included 165 finished sheets, eleven still to be engraved, and four sheets of Brittany, already surveyed but yet to be drawn. The Dépôt now had everything it needed to complete the map of France as it was originally envisaged way back in 1748: 180 map sheets of the entire country on a uniform scale of 1:86,400, with the addition of Cassini IV’s Carte des Assemblages des Triangles. But yet again circumstances intervened. Even the most recent maps now needed correcting and updating to include new roads, as well as the administrative reforms of the Republic’s departments. Reduced versions of the projected map of France were produced, but none matched the original plan. In 1790, prior to nationalization, Louis Capitaine drew up a reduced atlas based on the survey’s work, designed to represent the National Assembly’s reorganization of the regional departments. He also published the ‘Carte de la France suivant sa nouvelle division en départements et districts’. The map was dedicated to the National Assembly and the shareholders of the Société de la Carte de France, in a valiant attempt to accommodate their divergent political and commercial interests. It was also the first map to represent the reformed departments. But it was still not the comprehensive survey covering every corner of the country envisaged by Cassini III and IV.

  It is strangely appropriate that the individual who encouraged its completion and signalled its eclipse was both a revolutionary and an emperor: Napoleon Bonaparte. Having overthrown the republican authorities in 1799, he crowned himself Emperor Napoleon I in December 1804. Just weeks before his coronation, he wrote to his military chief of staff, Louis-Alexandre Berthier, concerning French troop movements across the Rhine. ‘The ingénieurs-géographes are being asked to make cadastres [property maps] instead of military maps, which means that, twenty years from now, we shall have nothing,’ he complained. He went on: ‘If we had stuck to making maps on Cassini’s scale, we should already have the whole Rhine frontier.’ ‘All I asked was that the Cassini map be completed.’53 As far as Napoleon was concerned, the scale and detail of Cassini’s maps were perfect instruments for military activity.

  Ten years later, as his enemies closed in on him, a small incident shows how far the Cassini maps had by then permeated and shaped the national consciousness. In February 1814 Napoleon spent the night in the remote village of Her, in the Champagne-Ardennes region, preparing for the Battle of Arcis-sur-Aube, which would prove to be the penultimate battle before his abdication and exile to Elba. Lodging with the local priest, Napoleon and his officers settled down to dinner, at which point, Napoleon’s faithful secretary Baron Fain recalled, ‘it was with difficulty that our host comprehended how his military guests could be so well acquainted with its localities, and insisted upon our all being natives of Champagne. In order to explain the cause of his astonishment, we showed him some sheets of Cassini, which were in every one’s pocket. He was all the more astonished when he found in them the names of all the neighbouring villages, so far was he from thinking that geography entered into such details.’54 That virtually all of Napoleon’s retinue owned copies of Cassini’s maps is testament to their military application. But their almost magical revelation in front of the incredulous priest also shows how far they appeared able to bridge regional differences (regardless of reality); above all else, priest and soldier were ‘French’, regardless of their religious or ideological differences.

  The Dépôt de la Guerre took over direct control of the publication and distribution of the remaining maps, appointing twelve engravers to update the confiscated plates and print new editions where necessary. The political and military importance of these maps ensured that state funding was always available, as Berthier had pointed out in a letter written to the Dépôt’s director in 1806: ‘with money, we shall lack for neither draughtsmen nor engravers.’55 There was clearly a brisk market for these new maps, as single sheets sold for 4 francs. Finally, in 1815, the last sheets of Brittany were finished, completing the full set of 182 sheets of maps. But when, after sixty-seven years, the Cassini map of France reached its end it was already a thing of the past. Seven years earlier, in 1808, Napoleon had ordered a new map of France. A report highlighted the errors and mistakes that were now glaringly obvious on the Carte de Cassini:

  The Dépôt de la Guerre, in possession of the plates of the Cassini map, has had every opportunity to verify its exactitude. It has unfortunately identified major errors; localities placed a league distant from their true position; the impossibility of precisely determining longitudes from the Cassinis’ data and calculations, etc. In addition, the Cassini plates, badly engraved to begin with, were almost worn out; a great many already retouched, many that will have to be engraved anew, an operation it makes no sense to undertake without making a great number of corrections, or, to be quite frank, a new survey.56

  The Cassini survey and its maps were ultimately rendered redundant not by the edicts of a king, or the ideological demands of a republic, but by what any modern nation state undertakes with continuous regularity – just another survey. By 1818 the first trials for a new survey were undertaken, although it was not completed until 1866, with the final maps (273 in all) published in 1880. New methods of measuring elevation and relief, including the clinometer, which calculated angles of elevation relative to gravity, ensured that the new survey offered a level of accuracy that finally surpassed the technical ach
ievements of the Carte de Cassini.57

  One of the most enduring consequences of the Cassinis’ endeavours was that they inspired the most famous of all national surveys, the British Ordnance Survey. In October 1783, less than a year before his death, Cassini III wrote to the Royal Society in London with a proposal to measure the difference in latitude and longitude between the observatories in Greenwich and Paris, using the methods of triangulation perfected by his engineers working across France, in the first truly cooperative international mapping project of its kind. Cassini’s telescopic instruments were able to locate positions in England from France, and he now proposed a trigonometric survey across the sea, uniting the two old adversaries in a chain of precisely measured triangles.58

  The proposal inevitably evoked old animosities between the two great European powers, and the Astronomer Royal, the Reverend Neil Maskelyne, grumbled at Cassini’s cheek in suggesting that English estimates of Greenwich’s geodetic position were inaccurate. But on this occasion, science overcame nationalism. The president of the Royal Society, Sir Joseph Banks, asked Major General William Roy to undertake the survey on the English side of the Channel, and in June 1784 Roy began work by painstakingly measuring the first base line of his survey on Hounslow Heath, west of London. Roy’s base line provided the foundation for the Ordnance Survey’s subsequent mapping of the whole of Britain, and it followed the same principles as Jean Picard’s base line drawn 115 years earlier west of Paris. The instruments were new and improved (including the introduction of a monstrous 200 pound theodolite, capable of measuring vertical or horizontal angles), but the methods pursued by Roy and the Ordnance Survey throughout the rest of the nineteenth century were exclusively based on those developed by Picard and the Cassinis in France. For Cassini III, exporting his surveying techniques across the Channel was the culmination of a geodetic project that had stretched back over 120 years; for the English, it was the beginning of a national survey that would ultimately gain even greater fame than the Carte de Cassini.59

  • • •

  The Carte de Cassini was an unprecedented step in the history of mapmaking. It was the first general map of an entire nation based on geodetic and topographical measurement; ‘it taught the rest of the world what to do and what not to do’.60 Its pursuit of an ‘esprit géométrique’, or ‘quantifying spirit’,61 begun in the mid-seventeenth century, gradually transformed the practice of mapmaking over the next 150 years into a verifiable science, pursuing a standardized, empirical and objective method that could (and would) be extended right around the earth. The cartographer was now regarded as a disinterested engineer, capable of matching the map to the territory. Reduced to a series of geometrical triangles, the world became knowable and manageable.

  But the claim of the Cassinis to pursue a disinterested, objective method of scientific enquiry was more of an aspiration than a reality. Looking back at his tenure as head of the Paris Observatory during his long retirement, Cassini IV wrote wistfully that ‘[e]nclosed in the Observatory, I thought that there I was in a port sheltered from all storms, beyond the sphere of jealousies and intrigues that we call the world. I saw in the movement of the stars only the noble and sweet contemplation of the marvels of the universe.’62 This was in part a disillusioned response to his treatment at the hands of what he regarded as the ruthlessly instrumentalist attitude of the new republican regime, but it avoided the fact that for four generations his family had acted in response to the demands of an absolutist monarch. From the foundations of the Académie des Sciences in the 1660s, the surveying and mapping of France by the Cassinis provided a direct response to the political and financial requirements of the rule of first Louis XIV and then Louis XV. Successive controllers-general saw the surveys and maps as a tool for the effective management of the state. From Colbert onwards, ministers demanded a new kind of geography that could help map transport networks, regulate provincial taxation, facilitate civil engineering works and support military logistics. The Cassinis responded – often brilliantly – to such needs, rather than developing their surveying methods from neutral, disinterested scientific speculation.

  The results of their methods were not as accurate and comprehensive as has sometimes been claimed. The sheer physical difficulties confronted by the engineers attempting to take precise measurements in adverse conditions using cumbersome and often limited instruments meant that, even after the conclusion of three surveys and the virtual completion of the Carte de Cassini, the Napoleonic authorities still found discrepancies in the position of locations, the omission of recently created roads and the measurement of longitude and altitude. The surveying was also highly selective in what it recorded. Those who bought individual sheets to see their local areas complained that certain features such as farms, streams, woodland and even châteaux were missing, even though the state wanted a ‘locational diagram of significant places’63 for specific administrative purposes, including taxation. Even Cassini III admitted that ‘[t]he topography of France was subject to too many variations for it to be possible to capture it in fixed and invariable measurements’.64 Paradoxically, the limitations of both the surveys and the incomplete Carte de Cassini proved to be among their most significant legacies, because they showed that any national survey was potentially endless. The accumulation of topographical data resulted in a vast complexity, which overwhelmed the initial geometrical skeleton of the first surveys. When we see the Cassinis’ engraved maps failing to record new roads, canals, forests, bridges and innumerable other man-made changes to the landscape, we realize that the land never remains static for very long, whatever the scientific claims to measure and map it accurately.

  Ultimately, the Carte de Cassini was more than just a national survey. It enabled individuals to understand themselves as part of a nation. Today, in a world almost exclusively defined by the nation state, to say that people saw a place called ‘France’ when they looked at Cassini’s map of the country, and identified themselves as ‘French’ citizens living within its space seems patently obvious, but this was not the case at the end of the eighteenth century. Contrary to the rhetoric of nationalism, nations are not born naturally. They are invented at certain moments in history by the exigencies of political ideology. It is no coincidence that the dawn of the age of nationalism in the eighteenth century coincides almost exactly with the Cassini surveys and that ‘nationalism’ as a term was coined in the 1790s, just as the Cassini maps were nationalized in the name of the French Republic.65

  In his classic study of the origins of nationalism, Imagined Communities, Benedict Anderson argues that the roots of national consciousness grew out of the long historical erosion of religious belief and imperial dynasties. As the certainty of religious salvation waned, the empires of the ancien régime in Europe slowly disintegrated. In the realm of personal belief, nationalism provided the compelling consolation of what Anderson calls ‘a secular transformation of fatality into continuity, contingency into meaning’. At the level of political authority, the nation superseded the empire with a new conception of territory, where ‘state sovereignty is fully, flatly and evenly operative over each square centimetre of a legally demarcated territory’. This is in direct contrast to empires, ‘where states were defined by centres, borders were porous and indistinct, and sovereignties faded imperceptibly into one another’.66

  The reasons for this shift lay in the transformation of vernacular languages and apprehensions of time. In the West, the rise of what Anderson calls ‘print-capitalism’ in the fifteenth century gradually signalled the ultimate decline of the ‘sacred languages’ of imperial and ecclesiastical authority, Greek and Latin, in favour of the vernacular languages spoken by a vast, new potential readership. The subsequent rise of the novel, the newspaper and the railway in Europe created a new perception of ‘simultaneous’ time, marked by ‘temporal coincidence’, and measured by the introduction of clocks and calendars. People began to imagine the activities of their nation ta
king place simultaneously across time and space, even though they were unlikely ever to visit or meet more than a tiny fraction of the places and people of which their nation is composed.

  But in a typical example of what has been called the ‘historian’s strange aversion to maps’,67 Anderson initially failed to consider the most iconic of all manifestations of national identity. If changes in language and time ‘made it possible to “think” the nation’,68 then a map’s potential to alter perceptions of space and vision make it possible to visualize the nation. The Carte de Cassini, created during the same period that railways, newspapers and novels rose to cultural pre-eminence, was an image that allowed those who bought it to imagine the national space in one glance. Moving from their particular region to the nation as a whole, and reading the map in the standardized language of Parisian French (something which was standardized by the revolutionary authorities from the mid-1790s), the map’s owners could identify with a topographical space and its inhabitants. As a result, the nation began the long and often painful process in the development of an administrative solidity and a geographical reality that helped to inspire an unprecedented emotional attachment and political loyalty from its subjects.