Problems with Triangulation
17
Imperial Land Survey Department; ground triangulation
plain
2020-08-15T11:28:46-04:00
1905-1945
Sakura Christmas
trigonometric survey; imperial cartography; Hunchun.
The photographic technology introduced by Kimoto revolutionized mapmaking in Manchukuo, which had relied on ground triangulation since the early 1900s. Ground triangulation used trigonometric principles to calculate distances and elevations across the land. Beginning in the eighteenth century, this cartographic practice emerged as one of the primary ways in which European colonizers came to 'know' their imperial acquisitions. As Matthew Edney contends, the rhetoric surrounding this practice gave colonizers a sense of mastery over distant places, expressing the paragon of imperial rule in ordering the land in rational, standardized terms.
Ground triangulation, nevertheless, was an arduous process. Teams of eight, ten, sometimes more, would spend several days in the countryside surveying. Sometimes they encountered bandits who occasionally robbed, even killed, workers. Out in these rural areas, they measured angles, distances, and elevations from a triangular network of known control points, called mapping chains, like this example from Hunchun near the Korean border. The known control points used by Japanese, however, overlapped entirely with Manchukuo's railroad network, which limited ground triangulation out in the hinterlands severely.