But that's not all we can learn from this advert. It's surprisingly full of useful information.
"GENUINE PORTER and ALES.
PETER GRANT, at his cellars, Niddry Street, Edinburgh, most respectfully informs his friends and the public. that he has got to hand, in addition to his former Stock, a large quantity of mild London Porter.— He has likewise on hand a large stock of excellent old and mild Ales, and Scots Porter, in perfection, for immediate use; the whole being brewed on purpose for himself, of a superior quality to any in the place, a trial of which will be found sufficient recommendation, and sells it at the following prices, in dozens, viz.
s. d Good London Porter, warranted free of mixture 2 9 Ditto Rack 3 0 Brown Stout 3 6 Scots Porter 2 0 Ditto ditto 2 3 Best double 2 6 Strong Ale 2 6 Double Ale 3 0 Ditto ditto 3 6 Double double 4 0 Treble Strong 5 0
As the above prices are three-pence cheaper on each dozen, than can be got of the Same quality elsewhere, no credit will be given. Bottles, if not returned, 2s. per dozen.
Ales from one month old to five years old.
N. B. Families can be advantageously Served with London Potter in hogsheads, as well as in bottles, carriage free to any place in town or Suburbs.
Commissions from the country carefully executed."
Caledonian Mercury - Thursday 11 May 1797, page 1.
I'm going to begin with mild. It's interesting that the Porter is specifically identified as Mild Porter. That is, Porter with no age on it. You might have expected Porter that was being shipped up to Edinburgh to have a little more age on it to help stability. Though the journey from London to Edinburgh wasn't as tricky as that to many other parts of Britain. Doubtless the Porter would have been shipped by sea directly from London to Leith. A relatively cheap and simple trip in the days before the railways.
That's Mild Porter, now let's look at Mild Ales. Though there are Stock Ales too, as it specifically says they have stock of Ale between a month and five years old. Lambic aside, I can't think of any modern beer that's aged as long as five years before sale.
Unfortunately, in the table of prices there's no indication of which Ales are Mild and which aged. It would be easy to assume that the stronger ones were the old ones, but that's a dangerous path to take. Ales of modest strength - though not usually the very weakest - might be aged and, conversely, Ales of great strength might be sold young.
Once again, the vast majority of the beers on offer are bottled. As we know, that's a particularly Scots habit. In England, most of these beers would have been sold in barrels. Though it's not explicitly stated, Peter Grant had almost certainly bottled these beers himself.
It says something about the frequency of adulteration - or at least the public's fear of it - that the advert states it's "free of mixture", i.e. it hasn't been tampered with. Unsurprisingly, the London Porter is more expensive than the locally-brewed Scots Porter. 37.5% more than standard Scots Porter, 22% more than posher Scots Porter.
I've no idea what London Porter Rack means. Presumably some better sort of Porter.
While we're on the subject of names, I particularly like Double Double. Shouldn't that be Quadruple? I'm guessing that the Ales were all brewed in Scotland. If the Ales were English it would surely have been mentioned. Which now has me wondering about the Brown Stout. Was that Scottish or from London?