Unrolling the old map

Text: an original contemporary personal account-style practice extract.

The map had been stored in a tube for decades, so I cleared the longest table in the study room before opening it. I spread clean cotton sheets across the scratched wooden surface, then carried the map over with both hands. Two foam weights stopped its curled corners from lifting. A volunteer offered to flatten the paper with heavy books, but I decided that their rough covers might leave marks. Once the map was secure, I began copying the faded place names into my notebook.

From the extract, identify what the writer spread across the table before carrying the map over.