I'll start with a caveat. There are only seven beers from just two breweries. A rubbish sample size. I would be very reluctant to draw too much in the way of conclusions from this handful of Pale Ales.
That fact in itself tells us something. Of the three large London breweries for which I have long sets of brewing records (Whitbread, Truman and Barclay Perkins) only Truman brewed a Pale in the 1840's. As I've mentioned several times before, the Scots were ahead of the game when it came to Pale Ale. That was a big factor in the success of Edinburgh and Alloa brewers: anticipating the demand for Pale Ale.
|Date||Year||Brewer||Beer||Style||OG||FG||ABV||App. Atten-uation||lbs hops/ qtr||hops lb/brl||boil time (hours)||boil time (hours)||boil time (hours)||Pitch temp||max. fer-ment-ation temp||length of fer-ment-ation (days)|
|23rd Oct||1845||Truman||Pale Ale||Pale Ale||1066.2||1017.5||6.45||73.64%||20.0||5.92||61||76.5||10|
|16th Mar||1846||Truman||Pale Ale||Pale Ale||1066.8||1019.1||6.30||71.37%||25.0||7.44||60||77||12|
|10th Jan||1849||Younger, Wm.||Export||Pale Ale||1061||1018||5.69||70.49%||20.00||5.41||1||2||56||65||6|
|24th Jan||1849||Younger, Wm.||Export||Pale Ale||1062||1015||6.22||75.81%||20.00||5.83||1.33||1.33||56||66||7|
|3rd Apr||1849||Younger, Wm.||Export||Pale Ale||1062||1014||6.35||77.42%||20.00||5.68||1.17||1.17||56||67||8|
|14th Nov||1849||Younger, Wm.||Export||Pale Ale||1063||1012||6.75||80.95%||20.00||5.95||1||1||56||67||9|
|7th Jun||1849||Younger, Wm.||Export||Pale Ale||1071||1017||7.14||76.06%||20.00||6.32||1||55||66||8|
|Truman brewing record document number B/THB/C/127 held at the London Metropolitan Archives|
|William Younger brewing record document number WY/6/1/2/3 held at the Scottish Brewing Archive|
Rather than go through point by point as usual, I'll restrict myself to more general comments. The beers are generally pretty similar. Truman's has a slightly higher OG, but Younger's is a bit more attenuated, leaving the ABV almost identical. That's a bit of a turnaround. So far in my comparisons the London beers have always been the most attenuated. I can't see any huge difference in the hopping. All the beers in the table contain a shitload. Considering how similar the beers are in other respects, the difference in fermentation temperatures is striking. The maximum temperature of Truman's beers averaged over 10º F more. Yet weirdly, the Younger's beers fermented for more than three days less on average.
Whatever the differences with Truman's, Younger's Pale Ale looks the part for the mid-19th century: moderate gravity, quite high attenuation, loads of hops. And nothing at all like the cliché of Scottish beer.