Arnold L.  Mumm was a  lifetime member of the Alpine Club and the Alpine Club of Canada. Arnold Mumm played a prominent role in the early exploration of the Canadian Rockies. Mumm, Arnold L. 

The UK Alpine Club started with 31 members in 1857, by 1900 it had 800 members. Contrary to common belief, most were not 'gentlemen', men with titles an inherited wealth and estates. They were mostly businessmen, bankers, finance, clergy, teachers, physicians, lawyers, public officials. Most had University degrees, 34% from Oxbridge.  

They were responsible for many of the first and early ascents in the Alps, the Golden and Silver Age. Their impact was not so much the actual climbing of the peaks as the publication of their climbing accounts, which inspired new climbers, informed old ones, and was enjoyed by a wide swath of the public.... and still is.

Mumm actually completed two more volumes of this register of the climbs of early members, carrying through 1900.  The dates are when the members were elected to the AC, not the dates of their climbs.

I (Michael Chessler) have had in my possession for many years the personal copy of the AC Register of all 3 Volumess previously owned by J. Monroe Thorington, not only a pioneering climber, but a bibliophile who loved climbing books and the history of climbing. In his copy, both in annotations and separate typed pages, are his recordings of many climbs by American members of the Alpine Club, that he intended to give to the AC for updating their records. I do not know if this was ever done.