This question already has an answer here:
I began to read the stories of Sir Arthur Conan Doyle's Sherlock Holmes, and several times already, I came across numbers the form of which surprise me...
First, in A Study in Scarlet, Chapter IV:
"Give me food," the other said, hoarsely. "I have had no time for bite or sup for eight-and-forty hours." He flung himself upon the cold meat and bread which were still lying upon the table from his host's supper, and devoured it voraciously. "Does Lucy bear up well?" he asked, when he had satisfied his hunger.
Then, in The Sign of Four, first in chapter II:
If she were seventeen at the time of her father's disappearance she must be seven-and-twenty now, — a sweet age, when youth has lost its self-consciousness and become a little sobered by experience.
Then in chapter VII:
The scent will lie upon the road in spite of their eight-and-twenty hours' start.
These numbers may also be found in some short stories, such as The Red-Headed League and The Five Orange Pips (and probably others, but I might come across spoilers if I search further...). Additionally, I also found "standard" numbers, for instance when giving time:
It was twenty-five minutes to twelve, and of course it was clear enough what was in the wind. (A Scandal in Bohemia)
... and even when talking about age (even though my first quote of The Sign of Four uses the other form) :
All red-headed men who are sound in body and mind and above the age of twenty-one years, are eligible. (The Red-Headed League)
While I understand that these respectively mean 48, 27 and 28, I am very curious two know more about this formulation, for instance: what is specific to the time? To some writers? Is it still used? Were there rules as to when it should and shouldn't be used? Or does it depend on who's speaking, and on the context of the discussion?