The Yu Chi
Fu, or map of the Tracks of Yu the Great was carved in stone
1137. It is known to have been in use for an indefinite period
before that. Like the portalanos of the West the real date of
origin is unknown. A comparison of the river system shown on
this map with that on a modern map of China shows a remarkable
accuracy (see Figs. 77 and 78). This map was evidently drawn
with excellent information as to longitudes, such as we find
on the portalanos, but do not find on the classical maps of
Greece and Rome, and which was certainly not typical of the
cartography of medieval China or Japan.
The Yu Chi
Fu with oblong grid constructed empirically from the geography.
As a further
test of the grid I had drawn for the map, I listed separately
all the northernmost and southernmost places identified on the
map and averaged their errors in latitude. I also listed all
the easternmost and westernmost places and and averaged their
errors in longitude (Tables 10b and 10c). The average error
of latitude on the north was less than one-half of one degree
(or 30 miles!), and the average error on the south balanced
out to zero (with four localities 1¹ too far south and four
1.2¹ too far north). So far as longitude was concerned, the
error both on the east and on the west balanced out to zero.
There was no indication, therefore that the grid constructed
for the map was seriously in error.
From Maps
of the Ancient Sea Kings by Charles H. Hapgood
