William Lawson's distillery at Banff, Scotland. After distillation the spirit is put into casks and then moved off to the bonded warehouse. Here the spirit spends the legal minimum of three years of quietly frantic chemical interaction with the wood of the cask before becoming scotch, and perhaps 10, 12 or more years maturing if it is destined to become single malt whisky. Bonded warehouses tend to be cool and sometimes damp places. Nonetheless, the wood of the casks is permeable and evaporation of the alcohol does take place. At a rate of about 2% per year of maturation, someone has calculated that the "Angels Share", the evaporated alcohol, amounts to about 150 million bottles per year across Scotland.
