Courage Strong Ale 1914 - 1917

We've just about done with Courage's beers during WW I. Just the Strong Ale to go. Isn't that a relief?

Let's kick off with the table:

Courage Strong Ale 1914 -1917
Date	Year	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	dry hops (oz / barrel)	pale malt	black malt	no. 3 sugar	other sugar	I.M. Co.	total
22nd Oct	1914	XX	Strong Ale	1079.22	1033.24	6.08	58.04%	10.00	3.07	2	2.5	1	60º	8.00	67.16%			14.93%	17.91%	100.00%
4th Mar	1915	XX	Strong Ale	1079.22	1033.24	6.08	58.04%	11.00	3.53	2	2.5	1	60º	8.00	67.16%			14.93%	17.91%	100.00%
5th Oct	1915	KK	Strong Ale	1076.18	1017.73	7.73	76.73%	10.00	3.10	2	2.5	1	60º		85.07%			14.93%		100.00%
19th Oct	1915	KK	Strong Ale	1076.18	1016.62	7.88	78.18%	10.00	3.10	2	2	1	60º		85.07%			14.93%		100.00%
5th Jul	1916	KK	Strong Ale	1076.18	1027.70	6.41	63.64%	11.00	3.42	2	2	1	60º		85.07%			14.93%		100.00%
4th Jan	1917	KK	Strong Ale	1075.34	1027.42	6.34	63.60%	11.51	3.54	2	2	1	60º	8.05	83.95%	1.33%	14.73%			100.00%
18th Oct	1917	KK	Strong Ale	1072.57	1023.82	6.45	67.18%	12.66	3.63	2	2	1	59º	8.44	83.58%	1.76%	14.66%			100.00%
Source: Documents held in the Courage Archives and the London Metropolitan Archives: ACC/2305/08/247, ACC/2305/08/248, ACC/2305/08/249

Wondering why there's not much of a cut in the gravity? That's because they discontinued the beer just as the draconian hacking started.

The grists aren't the miost exciting I've ever seen. Pale malt and sugar. With a dash of black malt in 1917. Oh, and I.M. Co (or is it IM C?), whatever that is. Some type of malt, that's for sure. It crops up in Truman's Burton logs, too. Not the foggiest idea what it is.  Any suggestions are welcome.