Clibit
Going by the stouts I've made i reckon this looks a good recipe. From shutupaboutbarclayperkins blog.

1936 Barclay Perkins RNS
mild malt6.75 lb52.78%
brown malt0.75 lb5.86%
amber malt1.50 lb11.73%
roast barley1.50 lb11.73%
flaked maize0.50 lb3.91%
malted oats0.04 lb0.31%
No. 2 invert sugar0.125 lb0.98%
No. 3 invert sugar0.75 lb5.86%
No. 4 invert sugar0.75 lb5.86%
caramel 1000 SRM0.125 lb0.98%
Fuggles 150 mins1.25 oz 
Fuggles 60 mins1.25 oz 
Goldings 30 mins1.00 oz 
OG1059 
FG1016.5 
ABV5.62 
Apparent attenuation72.03% 
IBU43 
SRM44 
Mash at143º F 
After underlet153º F 
Sparge at162º F 
Boil time150 minutes 
pitching temp60.5º F 
YeastWyeast 1099 Whitbread ale 
 
Quote 0 0
Robert
I'm sure there are a few more ingredients they could have levered in. Just before WW2. Nearly 80 years before we'd be getting stout at that strength again
Quote 0 0