Overall, two-thirds of Peiresc's published letters involved two cities. The geographical picture that emerges is different from that first provided by Mandrou. Clearly the method used here was more tedious but arguably more satisfying. Mandrou counted the number of correspondents by city . The present figures come from the number of letters by city .
Brief reflection suggests the practical requirements and theoretical implications of the method.
A s a simple distribution over time, the chronological picture holds few surprises. A steady increase in frequency is evident until the last two years of Peiresc's life. The greatest frequency is for years 1633-1635. Although the Brothers Dupuy and Gassendi represent a substantial percentage of these letters, this period also represents one of the most diverse in numbers of correspondents. T o illustrate these rather simple matters of fact, the following map and chart provide a crude picture of Peiresc's correspondence network as reflected in his published letters.