One of the kitchen's most familiar instruments used to be the rolling pin. In cartoons, it was what women waved when they were angry: Oor Wullie's Ma or Desperate Dan's Aunt Aggie, catching her boulder-chinned nephew at some mischief while she was cooking his cow pie.
Like many women of her generation, my mother must have used one four or five times a week, rolling a lump of dough thinner and thinner, occasionally flicking it with flour from a bowl or water from the tap; almost an industrial process, like making steel plate. Then the pastry would be cut and the oven lit. I am tempted to say that I "watched fascinated" as a small, embryonic chef, but the truth is that I paid hardly any attention - this was normal domesticity in the middle years of the last century, towards the end of the last great age of the homemade pie. The first food I can remember is potato pie - its iron crust, its dull interior sometimes flecked with corned beef - followed by apple pie. Later, in memory if not in fact, came steak pies, lemon meringue pies, apples pies laced with brambles or sultanas, and the advent of shop-bought flaky pastry.
My mother was a good cook. She once won the West Fife Women's Rural Institute prize for the best fruit slice. I like to think that her potato pies were an aberration brought on by food rationing and the years we spent in Lancashire; mainly, her pies were delicious, succulent in the way that the gravy from the meat or fruit soaked into its crisp surroundings on the plate. Even so - and perhaps this feeling about pies stretches far back in history, four and twenty blackbirds and so forth - I was aware that both the charm and danger of a pie lay in its invisible contents. My brother would tell me the story of the human finger (or was it a toe?) that a customer found in one of Mrs Lovett's meat pies, evidence of insufficient processing in the supply chain from Sweeney Todd's barbershop next door. I never found anything quite so disturbing in a pie, but in Scotland they could contain unpleasant surprises. There was always the danger of discovering fat and gristle in steak pies eaten outside the home, as well as (still a favourite Scottish ingredient) cheap pork sausages nestling among the stewing beef.
Pies are very old. The Greeks and Romans had them, but for hundreds of years they were nothing more than primitive tin cans, the pastry shell preserving the meat and moisture inside, to be cracked open and thrown away. England knew them as coffyns. By the 16th century, according to the food historian Colin Spencer, England had two kinds of pies: the smaller, all-edible variety with a wheat-flour crust, and big ones baked in an oven for eight or nine hours, whose rye-flour casings were fed to the hogs. They might contain chicken or swan, rabbit or porpoise. They were built to last, sealed with clarified butter and sent as presents from country to town, where they could stand on a sideboard for several weeks and diminish slice by slice.
This was food for the rich or the quite well-off. Slowly, the pie became demotic. By the early 19th century, London was filled with pie shops (perhaps including Mrs Lovett's) and pie men (perhaps including the one Simple Simon met) hawking their wares around streets and pubs. Its progress in Scotland is not so easily discoverable and may have been stilted by the tradition of putting offal and poor cuts of meat to work in haggis and other savoury puddings. None the less, industrial Victorian Scotland went crazy for pies. Steak pies became a feature of funerals, weddings and New Year feasts. The humbler mutton pie (formerly the tuppenny pie, now the Scotch pie) was a favourite of workers' lunchtimes and football half-times, and now graces every butcher's and baker's; its top crust, lying about half an inch underneath the rim, makes an ideal container for baked beans, peas, mashed potato, macaroni cheese, curry sauce, the ready-made combinations that cheerfully decorate the stew underneath (and add their weight to the great Scottish health problem).
For me, a pie crust needs to go all the way: top, bottom and sides. Fish pie and shepherd's pie, open fruit pies and the poseur steak pie you sometimes find in restaurants (a microwaved bowl of stew with a pastry hat added): these are not proper pies. When I think of pies, I think of a poster you sometimes see in Scottish bakeries. Say Aye to a Pie, it says, showing a brave little chap of the Fry's Five Boys kind (and therefore slightly historic) tucking into one. I know what he means: the juicy fat of the mutton pie, its indefinable meat, the crunchy shell that's so neutral in taste it also gets used for the bakery's rhubarb and apples pies, which are also in the window along with the Forfar bridies, the sausage rolls and the potato scones.
I move on from the sight of such a baker's window reluctantly.