Why is Perrault interested in keeping the Nordic and Latin races of Europe? Why does he consider them his best subject? (chapter 8)

The Nordic and Latin races of Europe are adaptable to Shangri-La's altitude.

Our best subjects, undoubtedly, are the Nordic and Latin races of Europe; perhaps the Americans would be equally adaptable, and I count it our great good fortune that we have at last, in the person of one of your companions, secured a citizen of that nation.