Thump, thump, thump. In the frantic last hours of U.N. climate talks in Scotland, a senior diplomat from Luxembourg came sprinting down a hallway inside the summit venue, his hair flying as he whooshed by clutching a sheaf of papers, only to vanish inside an office as abruptly as he appeared. The final stretch of negotiations over what nearly 200 governments will do next about fossil fuels heating the Earth to disastrous levels was like that Friday: National delegations engaged in frenetic, often mysterious activity as they haggled to get as much of their position as possible into the final agreement from the talks in Glasgow. U.S. diplomats mostly worked behind closed doors, with terse signs on the glass. The open doors of most other country's offices – South Korea, Ivory Coast, Austria, and others – showed rooms full of diplomats bent intently over their laptops, eyes fixed on screens and fingers flying over keyboards. Chinese diplomats crowded into one of their offices stopped working, laughed and took photos when a wayward robin hopped in among them, lost in the warren of temporary tents and the event center. In the office of India's delegation, there was muted excitement. Delegates sat cross legged on the floor, typing furiously on their laptops. A vase in the office held fresh pink lilies. Endless cups of chai flowed in preparation for what would be a long night.