The following text is adapted from “Cambridgeshire Encompassed" by WBro JM Whitehead,
from whom permission to include this information from his copyrighted work is gratefully acknowledged.
Alma Mater Lodge was originally founded in Bletchley in 1874. The Lodge owes its existence and survival primarily to the initiative and enthusiasm of one man, John Studholme Brownrigg (1841-1930). He envisaged a Lodge meeting at some place readily accessible to Cambridge, which would not compete with other university lodges and which involved "less exacting" work than the Isaac Newton University Lodge, (INUL) which is particuarly focused on undergraduate freemasons. According to his letter of March 1874 to the Grand Secretary, Brownrigg’s notion was‘intended as a Lodge of ease to the Isaac Newton University Lodge at Cambridge, that Lodge being so overcrowded that many eligible candidates for the Master’s Chair are shut out. It is started in a place acceptable to Cambridge and London and not either in Cambridge or London as we desire to guard against any possible rivalry either now or at any future time with existing University Lodges.’
Unfortunately meetings at Bletchley were not well supported and attendance was very poor. There were held twenty meetings there, all on Saturday afternoons, the times depending on the current train timetable, but the average attendance was about six, being four or less on at least six or seven occasions. There were no Initiations only sixteen Joining members, all from INUL and the only Masonic ceremony performed was Installation. However, perhaps the nine Masters installed there may never have managed to reach the Chair through INUL. Most of them got there within two years of joining. To that extent the Lodge ‘eased’ the problem of scores of Undergraduates entering a Lodge that regularly performed three ceremonies per evening, held numbers of ‘Emergency Meetings’ for the purpose and Initiated, Passed and Raised candidates in large groups at times. It was a much different workload in Alma Mater.
In 1883, when Brownrigg was appointed to a post in London, it proved impossible for him to continue bearing the main load of the Bletchley Lodge on his shoulders. The May meeting had to be cancelled and the four members who attended the next Lodge night decided to apply for the meetings to be transferred to the University Arms Hotel, Cambridge. This might be seen as negating the original principle of the Lodge and it is true there was considerable misgiving in the ranks of INUL Past Masters, but the change took place. At the end of 1885 the Lodge met in the University Arms and their first candidate for Initiation was proposed. At first the Lodge endeavoured to avoid conflict of interest - although it seems an odd way to do it - by meeting on the same day and at the same time as INUL (even whilst a ‘tenant’ of INUL at the Corn Exchange Street Masonic Hall) but an amendment of Alma Mater By-laws in 1901 returned them to Saturdays and made it clear that University members of MA status were the natural and only recruits to Lodge 1492. Alma Mater now functions as a more or less standard Lodge specialising in University graduates though still with a particularly close 'family' relationship to INUL.