Sandra and jdc, thank you both very much for the information. Just what I was looking for. The LAC really are organised when it comes to WW1 records. The National Archives in London are a nightmare. I was down there recently and made a half-hearted attempt at finding the War Diaries for my Canadian Great Uncle's brother, my grandfather who joined the Royal Scots in 1914, and was buried in index volumes. I couldn't even work out his battalion. Fortunately, that wasn't the primary reason for going. None of the British diaries are on-line yet as far as I can see. I suppose it's the numbers, the Canadians were fewer than the Brits. I was researching the war of my other grandfather in 1942 Malaya and, purely by chance while looking for something else in Box 49 of General Percival's papers in the Imperial War Museum, came across the War Diary for the unit of sappers that Grandpa, as a civilian engineer, was attached to.
God help anyone looking for that! The papers aren't even indexed.
Jenny