Flinders had by that time completed his explorations, but his work was not yet published.

The map delineates the contour of the continent on the east, west, and north sides, with as much accuracy as was possible, and, though it is defective in details, presents generally a fair idea of the country's shape.

But the line along the south coast represents a total lack of information as to the outline of the land.

Pinkerton, indeed, though he was a leading English authority on geography when his book was published, had not embodied in his map some results that were then available.
The testimony of the map may be augmented by a reference to what geographical writers understood about Australia before the time of Flinders.
Though Cook had discovered the east coast, and named it New South Wales, it was not definitely known whether this extensive stretch of country was separate from the western "New Holland" which the Dutch had named, or whether the two were the extremities of one vast tract of land.
Geographical opinion rather inclined to the view that ultimately a strait would be found dividing the region into islands.

This idea is mentioned by Pinkerton.