My mother, Marjorie Allen, did not as far as I know keep a diary in the normal sense of the phrase. However, she wrote articles on subjects that she found interesting and important. One such article was written after the occasion of the Governor of Tanganyika's visit to Kondoa on the 23rd June 1950. There was no year added to the article however the only Friday 23rd June in the late 40s/early 50s fell in 1950.
Hopefully this will give some flavour of colonial life at the time.
I have copied her writings and sketches to PC and they can be found as an attachment to this post.