Langmuir attended the independent school Fettes College in Edinburgh (1943–1950) and, after national service, Peterhouse, Cambridge, where he read natural sciences (Geology, Zoology and Physiology) from 1952 to 1955.
[1] Soon after his return to the UK he was appointed as Principal of the White Hall Centre for Open Country Pursuits,[7] near Buxton, (1959-63)[1] which had been established in 1951 by Sir Jack Longland (in his role as Director of Education for Derbyshire).
[12] After his stint at Glenmore, he was appointed to set up an outdoor education unit at Moray House[13][14] in Edinburgh,[15] where he worked from 1970 to 1975 and became a senior lecturer.
[15] Langmuir was asked to initiate and edit a new handbook for all those taking part in the Board's training schemes,[15] and the resulting book, Mountaincraft and Leadership, was first published in 1969.
[22] The book remains in print 20 years after his death and is "the indispensable bible for all who would take parties of young people into the hills".
[23] In recognition of his pioneering work on avalanche prognosis in Scotland, for his publications and his personal contribution to outdoor education and safety in the mountains, Langmuir was elected a Fellow of the Royal Society of Edinburgh in 1978.