In 1893, Hung Ta-chen, a senior Chinese official at Kashgar, handed a map of the boundary proposed by China to George Macartney, the British consul-general at Kashgar.[14] This boundary placed the Lingzi Tang plains, which are south of the Laktsang range, in India, and Aksai Chin proper, which is north of the Laktsang range, in China. Macartney agreed with the proposal and forwarded it to the British Indian government. This border, along the Karakoram Mountains, was proposed and supported by British officials for a number of reasons. The Karakoram Mountains formed a natural boundary, which would set the British borders up to the Indus River watershed while leaving the Tarim River watershed in Chinese control, and Chinese control of this tract would present a further obstacle to Russian advance in Central Asia.[10] The British presented this line, known as the Macartney–MacDonald Line, to the Chinese in 1899 in a note by Sir Claude MacDonald. The Qing government did not respond to the note, and the British took that as Chinese acquiescence.[8] Although no official boundary had ever been negotiated, China believed that this had been the accepted boundary.