He writes, that (walled) Kaifeng covered 49 square kilometers, which was "13 times the size of 1292 Paris" and had a population (in the prefecture) of 1,3 million vs. 59.200 in Paris (this is the only comparison he makes). This would mean that a citizen of Kaifeng had only around 60% of the space of a citizen of Paris. Later on he makes a comparison like this himself: "The northeastern boroughs of the old city housed 79,500 inhabitants, while the eastern borough of the new city was home to 134,000 residents. 50 or more people per 1,000 square meters lived door by door, including an unknown number of unregistered households. Compared to Paris 1292, with its 59,200 inhabitants living on 3,78 square kilometers (16 persons, per 1000 square meters), the population of the song capital was 2 to 3 times as dense".