John B. Henderson

The Commentarial Tradition

In the Confucian tradition, few students of the classics read canonical writings without the aid of some form of gloss or commentary. Not only was commentary necessary to illuminate the numerous obscurities in the canonical texts, but also to defend against heterodox interpretations that might arise from “naive” explanations of the “plain meaning” of the text. But however valuable the services that commentators performed in illuminating obscurities in the canonical texts, this was not the only and perhaps not even the principal function of commentaries. Commentaries to the Analects also served a polemical purpose, to establish that the text lived up to a fairly universal set of criteria.

Mapping China and Managing the World: Culture, Cartography, and Cosmology in Late Imperial Times. By Richard J. Smith

In the English language, the word meridian means a line running north–south through the Earth’s poles, however determined and for whatever purpose. The French language distinguishes between le méridien and la méridienne, the former being the abstract line of points of the same longitude and the latter being a real line serving as a baseline for geographic measurements (or the visible line of a sundial showing noon local time). A méridienne is the practical realization of the theoretical concept of the méridien along which it is oriented. One might, with some approximation, say that the méridien (together with the equator) is the astronomical basis for latitude and longitude and the méridienne is a geodetic basis. The problem of fitting together a modern map can be described as the process of making an astronomically based coordinate system of latitude and longitude, including the determination of a méridien, laying it out in some way on the ground as a méridienne and an east–west traverse, and then interpolating key locations by surveying techniques into that framework. The survey that founded this mathematical process is reckoned to be Willebrord Snell’s survey of the Netherlands, made prior to 1615. The first map of an entire country in which the process was implemented accurately and in full was initiated in 1665–1666 by the French minister, Jean-Baptiste Colbert, who created the Académie Royale des Sciences in order to create a cadre of scientists to investigate scientific problems like this. The méridienne for this survey passed through the centre of the building of the Paris Observatory and was physically inscribed across France from Dunkerque to Perpignan and on to southern Spain through a series of markers, many still visible on the French landscape. Under four generations of the Cassini family of astronomers, the successive directors and chief scientists of the Paris Observatory, cartographers finished publishing the map as the Carte de France de Cassini in 1790. In Britain, the mapping of the country, indeed the Empire, proceeded in parallel through the foundation of the Royal Observatory at Greenwich in 1675. The fundamental meridian was defined to pass through the crosshairs of a telescope in Greenwich. Further meridians were constructed by various national authorities and groups of astronomers and geodesists in many parts of the world, including South Africa, India and Nepal, Lapland, Russia, Ecuador. East–west traverses were constructed in France and other countries of western Europe and elsewhere, and along the Mediterranean coast of North Africa, mostly in Algeria. Maps based on these fundamental geodetic skeletons could be joined across the sea by surveying only with difficulty and between close shorelines. The British and French surveys were joined across the English Channel, and Spain and Algeria were linked across the Strait of Gibraltar. Eventually, the electric telegraph made possible the near-instantaneous transmission of time signals so that astronomical longitude differences between two independent surveys could be accurately determined even when they were maps of areas thousands of miles apart. The individual geodetic skeletons could be knitted into one system, a unified imago mundi. There was no controversy over the zero of latitude or the relative separation of individual maps, but the zero point of longitude was arbitrary and the controversy over which longitude to choose was political, nationalistic and long-lasting, polarized in particular between Britain and France. The argument was solved by the government of the United States under pressure from the railroad companies who needed an agreed system of time zones, dividing longitude into blocks, to construct integrated timetables for east–west travel from one railroad company to another, across North America. The Washington Conference of 1884 chose Greenwich as the prime meridian. This book by two historians of science describes these geodetic surveys in chronological order, and their integration. It reproduces historic maps associated with the surveys (some of them, unfortunately, in low resolution images on which place-names and legends cannot be read, and none of them in colour). It quotes copiously from original documents. It is a meta-reference work that points through its footnotes and the modern historical works listed in the bibliography to the original sources, but its usefulness for research is diminished by its lack of an index and an analytic table of contents in which chapters and sections are given elliptical headings. It well describes the extraordinary scope of the fundamental surveys carried out in the mapping of the world and is a straight-forward record of one of the first Big Science projects of international cooperation, a precursor to the space projects and particle physics experiments of the present era.