Transportation via waterways was crucial in the 18th century Hamburg region. Therefore, this map recorded waterways in details. Following the blue color wash, readers can easily identify most of the waterways. Furthermore, the map showed the ebb and flow of the Elbe river, which was useful for navigation. However, the information about the depth of water was not provided. Although the color wash did show a gradation, it seems that the function of the gradation was only to distinguish water from land. (The parts close to the coasts were painted in dark blue, and the parts far from the coasts were painted in light blue.)
As the map did not have a legend, three details about waterways need further investigation: (1) A few waterways were not colored. Does it simply mean that these waterways were too narrow to color during printing, or does it have further implications? For example, these waterways may be impassable for larger boats. (2) On the western part of the map, two dotted lines were drawn adjacent to land. The meanings of these lines need to be clarified. (3) In the inset at the upper-right corner, something looks like the alluvium was depicted.
