In the filling store the barrels were filled from the main store, the entire operation overseen by the exciseman.
Each barrel was weighed empty and full and a sample of the whisky measured to check it alcohol content (normally about 60 per cent by volume). These measurements allowed the exciseman, working from his little booth in the corner, to calculate how much alcohol had been produced by the distillery.
The warehouses, or bonds, were strictly controlled by the exiseman. Until the tax was paid on a barrel of whisky (normally when it was bottled), it was the exciseman's job to ensure that none of it left his control; if it wasn't under lock and key in the bond, then he had to accompany it at all times.