As this valley bas never been visited by an European traveller, the little I have to say about it may make it acceptable to the Society. On one occasion I tried to visit it in company with Dr. Hooker, but unsuccessfully, as, after reaching the top of the Chola Pass—14,900 feet—which leads into it from Sikim, we were met by an officer of the Chinese Government at Lassa, with a military escort, who refused us permission to enter the valley. The particulars I have to state may, I believe, be relied on, as during many years I had constant opportunities of communicating with traders and others residing in the valley, in addition to the officials of the Sikim Raja, who annually sojourned in it from May to November. The route from Darjeeling to Choombi was described by me many years ago, as also the route from it to Lassa; but no one has described the valley itself.