Imperial Russian Stout 1849 - 1986

Someone commented on a post a few days ago about Barclay Perkins beers in the late 19th century, remarking on the pitiful OG of Russian Stout in 1946. Had the terms "Russian" and "Imperial" become meaningless by the middle of the 20th century.

My reply was that the low gravity was connected with the war and later went back to the classic 1100º+. Want proof? Well, obviously, I've got plenty. From a couple of different sources.

Russian Stout was extremely unusual in being almost exactly the same gravity in 1986 as in 1847. I can't think of another beer that managed to get through the two World Wars with no drop in gravity.

If you're wondering why the rate of attenuation is greater in the examples from 1938, 1950 and 1953 is greater, the answer is simple. Those are analyses of the finished beer, after the secondary Brettanomyces fermentation. While the others are taken from brewing records and the FG is at the end of primary fermentation.

Imperial Russian Stout 1849 - 1986
Year	OG	FG	ABV	App. Atten-uation	colour
1849	1104.9	1031	9.78	70.46%
1850	1109.0	1031	10.32	71.57%
1855	1107.2	1033	9.82	69.22%
1856	1106.9	1033	9.78	69.14%
1859	1105.3	1033	9.56	68.65%
1922	1100	1030	9.15	70.00%
1924	1103.4	1040	8.39	61.32%	420
1928	1102.8	1042	8.05	59.16%	680
1929	1102.7	1037.5	8.63	63.49%	340
1931	1102.9	1040.5	8.26	60.65%	460
1936	1102.5	1034	8.93	66.83%	400
1937	1104.5	1041.5	8.33	60.29%	380
1937	1102.7	1023.2	10.47	77.41%
1938	1101.5	1024.1	10.18	76.26%
1950	1100.1	1021.1	10.41	78.92%	350
1953	1101	1018	10.97	82.18%	500
1981	1101.8
1986	1104
Source:
Barclay Perkins brewing records held at the London Metropolitan Archives, document numbers ACC/2305/1/540, ACC/2305/1/542, ACC/2305/1/544, ACC/2305/01/611, ACC/2305/01/614, ACC/2305/01/621.
Whitbread Gravity books held at the London Metropolitan Archives, document numbers LMA/4453/D/02/001 and LMA/4453/D/02/002.
Good Beer Guide 1982 and 1987.