It's the 1880s. Nothing is on television, because television doesn't exist. No smartphone, no laptop, no endless internet of divertissement.
On a cold winter's night, you sit beside the fireplace with the rest of the household, doing whatever small task the lighting and your skillset allows.
If you're Sherlock Holmes and Dr. Watson, such a night could mean one thing: story time.
There are two little biographical sketches in Watson's writings about Sherlock Holmes that have nothing at all to do with a case at hand, and we find them in the opening paragraphs of "The Gloria Scott" and "The Musgrave Ritual." Both are set on a winter's night at Baker Street, and one can easily surmise that the scene in "Musgrave Ritual" comes first.
Sherlock Holmes has finished pasting clippings into his commonplace book of compiled data for future reference on cases, and John has suggested that Sherlock start cleaning up all the loose papers that are stacked about the room. Holmes then drags out a large tin box to start putting the documents into and discovers the souvenirs that lead him to a reminiscence about the Musgraves and their ritual.
It is easy to see this clean-up going into a second evening, when Sherlock Holmes stops to tell John H. Watson about a second set of papers he has come across, going to a drawer to pull out a souvenir whose importance is special enough that it's not kept in the tin box with the Musgrave trinkets. And thus begins the tale of the secret survivors of the sinking of the Gloria Scott.
When did this evenings take place?
Before Holmes goes missing in 1891, to be sure. Before Watson moved out in 1889, also a pretty definite deduction. Watson has already made a start to collecting his own write-ups of Holmes's cases, as evidenced by Holmes's wrap-up of "Gloria Scott" with the words "Those are the facts of the case, Doctor, and if they are of any use to your collection, I am sure that they are very heartily at your service," as well as Watson's reference to "these incoherent memoirs" in "Musgrave."
If Watson still considers his memoirs "incoherent," he plainly hasn't had the validation of a literary agent or publication yet, which puts the winter in question prior to 1887. And yet both Watson and Holmes seem to be pretty invested in the idea of Watson as biographer, like he's been taking a lot of notes. And Watson's mention that Holmes files his documents "only once in every year or two," if taken similarly as a thought of that period, means he had been with Holmes a few years.
Thus the winter of 1886 seems, perhaps, the most likely time for both "The Gloria Scott" and "The Musgrave Ritual" to be an evening's entertainment for Holmes to occupy Watson with. They are fascinating stories in that neither of them is actually told by Watson . . . he just writes the stories of Sherlock Holmes telling him the stories. One could almost imagine Watson intending to do an entire volume of tales Sherlock Holmes related to him over several winter nights in Baker Street, only to have real investigations come along that were much more engaging.
But it is those two stories that really give The Memoirs of Sherlock Holmes its title, and give us a window into a completely different sort of Canon that might have been. For as much as we talk about finding Watson's tin dispatch box for entertainment value, that larger tin box that Sherlock Holmes drags out of his bedroom in the opening of "Musgrave Ritual" would be the true treasure trove for the Sherlockian scholar.
And if you also had Sherlock Holmes to narrate the tales of what was in it, as Watson did on cold winter nights by the fire . . . what Sherlockian could ask for anything more?