Colquhoun was perhaps the first western 'traveller' in Yunnan, not a government official nor trader, and he covered, under his own steam and expense areas that few tourists today set foot on. Like all his fellows from his and our time, maybe he should have complained a little bit less about the food and the accommodation. An interesting read by a true pioneer.
Volume 2 of Colquhoun's journey through Yunnan, equally readable.