This week's assignment was pretty interesting and involved georeferencing historical maps to contemporary maps. The light yellow map above is a map of Macao (China) produced by Captain Cook (and William Bligh) in 1775. This map was obviously created at a time both latitude and especially longitude were difficult to determine with high accuracy. To "fit" this map to a modern map, we use Control Points to match landmarks that appear to be unchanged over the time between the two maps. A lot has gone on in Macao since 1775. In particular, there appears to be a lot of land reclamation that filled in areas between the islands of Macao. To find control points, it was especially useful to look at a topographical map and look for the landmarks that would have stood out to sailors mapping from a ship. In a few places (particularly to the north) we see a great deal of distortion. This is either the result of inaccurate distances in the original map or mismatch on my part. However, most of the smaller islands seem to be in about the right place.
This was a pretty fun assignment and one that will be super useful for anyone doing historic archaeology.
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