两张英藏晚清广州洪兵舆图成图时间再考——兼及舆图成图时间考证的“断限逼近法”

A Revisit on the Drawing Time of Two Hongbing Military Maps of Canton During the Taiping Rebellion,Now Held in the National Archive,U.K.Based on the "Approaching from Both Termini" Method

成图时间考证是传统舆图研究中最初步最重要的工作,本文利用"断限逼近法"重新考察两幅清代广州洪兵舆图的成图时间。通过对新发掘档案的梳理,判断将F.O.931/1079图的成图前限推至咸丰四年六月二十四日的结论尚不成立,而F.O.931/1892图的成图断限则可由原来的八月三十日至九月初五日进一步推断为九月十一日至十二日。

Determining the drawing time of traditional maps is an important and fundamental task.Based on the"approaching from both termini"method,and literature and archive review,this paper offers a revisit on the drawing time of two Hongbing(Hong army)military maps of Canton during the Taiping Rebellion,which are now held in the National Archive,U.K.It cannot be clearly proved if the first map(F.0.931/1079)drew on July 18,1854,whereas the drawing time of second map(F.0.931/1892)can be determined on November 1-2 of the same year,from the period of October 21-26.