Issue and Reserve

Issue and Reserve keep supplies on their own: a furnace always has coal, a workbench always has planks. Issue, painted on a storage, answers orders: things are taken from it for a Reserve, for an Operate and by the Ledger. By itself it carries nothing out.

Reserve keeps a number of the filtered items in its storage (the number is in the sigil's window). The automaton takes the shortfall from a known Issue or Stow on another storage and carries it over — so the furnace always has coal and the workbench always has planks. Next: "Tally Ledger".