At the time of writing, databases list over 500 examples of sundials and water clocks from the Greek and Roman worlds. These clocks range in date from the 4th c. BCE to the end of antiquity and appear in both urban and rustic settings throughout the Roman Empire. Monumental sundials and water clocks have been found in sanctuaries, marketplaces, and theaters; smaller, fixed clocks appear in bathhouses, gymnasia, and gardens; while portable devices have been found included among grave goods, dedicated as offerings in temples, or simply left lying in the street. Although our early Hellenistic written sources are fairly tight-lipped, writers under the Empire refer to clocks and the unit of the hour within a variety of genres (astronomy, geography, medicine, philosophy, poetry, military narrative), and the sundial even becomes a recurrent iconographic feature on friezes, mosaics, and gemstones. To navigate this body of evidence is a challenge; individual texts and objects are often enigmatic and widely scattered in space and time. Yet, one thing is clear: by the Imperial period, many inhabitants of the Roman Empire had incorporated horology into their worldviews.
It is surprising, then, that histories of horology have tended to begin only with the Medieval period and the introduction of the mechanical clock. The study of ancient sundials and water clocks, on the other hand, has traditionally been the preserve of historians of science, who are more often concerned with technical issues of the design, classification, and accuracy of clocks than with their social functions. Meanwhile, social historians of the ancient Mediterranean have focused their attention on other modes of timekeeping: calendars, chronological systems, parapegmata, and devices like the Antikythera Mechanism. Only now are scholars beginning to explore the practical functions and symbolic valuations of Greek and Roman clocks.
The present paper contributes to this discussion by focusing on the use of clocks and hours within the corpus of a single author: Galen of Pergamon. Because of the magnitude and range of his writings, it is possible to identify significant patterns in his application of these timekeeping tools; he restricts their use to particular contexts within particular genres, namely, works that deal with questions of logic, moral philosophy, and technical medicine. These patterns of use have important implications for our understanding both of Galen’s rhetorical strategies and of the practical and semiotic roles played by clocks and hours in Galen’s time.
While the wider project from which this paper is drawn examines each of these contexts in detail, the present paper focuses specifically on the ways in which Galen uses clocks and hours within technical medical contexts. It first groups these contexts into five categories: those in which Galen (1) defines the crisis points within periodic fevers, thereby creating an elaborate system for diagnosis; (2) describes individual dietetic regimens; (3) explains the concept of a ‘rate’ to beginners learning about the pulse; (4) contributes to the debate over how one should define the temporal boundaries within which a fetus can be called a ‘seven-month child’, and (5) updates Hippocratic flat-earth astronomy in order to account for the earth’s actual roundness.
The paper asks two questions of this material. First, how does Galen’s use of clocks and hours in these contexts compare with other textual and material evidence for contemporary healing practice? Second, why did Galen choose to employ clocks and hours in these precise fashions? Ultimately, the paper argues that - while Galen’s applications are assumed to be intelligible to his audience, and some are even paralleled in other sources - the extensive temporal regulation and precision that Galen advocates in his medical texts may have been intended more as a virtuosic display of erudition than as a reflection of contemporary medical practice.
Representation of Time in the Hellenistic and Roman World