Want to read this along with me? This essay is part of The Valley of Fear, published in 1915. I used the epub version found on Feedbooks.com.
The Valley of Fear actually features Moriarty a fair amount, although he never appears in the book – if “The Final Problem” is the best source for learning about how Moriarty is as a man, this book is the great for bits about Moriarty’s organization and the people around him. We learn that he pays his men well, and for their intelligence (“the American business principle”). He is a very firm leader, and any violation of his word results in death. He has an agent named Porlock that either betrays him or pretends to betray him to lure Holmes out – different Sherlockians have argued different interpretations on that, as well as offering a variety of opinions on who “Fred Porlock” really is.
We also learn another piece about Moriarty’s family. In “The Final Problem,” Watson mentions that Professor Moriarty’s death is defended by his older brother, Colonel James Moriarty. And yet, in this story, it is mentioned that his younger brother is a station-master in the west of England. Does Moriarty have two brothers?
However, there is a big problem with all this Moriarty business. “The Final Problem” makes very clear that Watson had not heard about Moriarty before that case, and Holmes was equally clear that very few people knew of him or his deeds. And yet, both of these facts are contradicted here: Watson clearly heard of Moriarty in this case (which has to be before “The Final Solution”), and MacDonald also knows about Moriarty. Trying to date this case after “Problem” isn’t any easier – why isn’t anyone concerned that Moriarty isn’t dead, or that Moran isn’t in jail?1
The text doesn’t help the task of dating the case any. The most obvious method is to take the explicit year reference in the second half of the book (1875), and combine it with that section’s reference of “I wish you to journey back some twenty years in time….” 1875 plus twenty years leads to the case being in 1895, which is after the Great Hiatus. Watson (typically, at this point) doesn’t mention his wife, so it could be either before his marriage in 1888, or after his “tragedy” in 1894. But when Holmes meets up with MacDonald, there’s a reference to “the early days at the end of the ’80′s,” which puts it before the Great Hiatus. Madness!
There is simply no way to reconcile the facts without ignoring some of them. I am more inclined to discount the second half of the book (for many reasons…), stick with the bulk of the evidence in the first half, which points towards a case around 1887 or so, and pretend that Watson created the effect of asking about Moriarty as a narrative device rather than a literal conversation that happened in 1891. At least Holmes’ deduction of what book to use for the cipher (another good example of object-based deduction) tells us that the case starts on January 7th. 2
Speaking of MacDonald, Holmes’ relationship with the two police characters is quite interesting. We’re told that Inspector MacDonald is rather famous, although we never hear of him before or after this case. He has, by the time of this story, consulted Holmes twice in the past. And yet, Holmes refers familiarly to MacDonald as “Mr. Mac” multiple times, while Lestrade and other detectives are only referred to with courtesy and their full title.
It’s a bit easy to cast that aside as a fluke, perhaps, but the respect that Holmes shows both men is displayed over and over again. Once, the two policemen quickly accept Holmes’ theories and discard their own almost immediately – no stubborn Lestrade trying to cram his theories down Holmes’ throat. In return, Holmes mentions explicitly that he would “play fairly” with them, and he offers to hand the case over to the official men as soon as possible.
“I only wish to verify my details in one way, which can very readily be done, and then I make my bow and return to London, leaving my results entirely at your service. I owe you too much to act otherwise….”
Where’s the personal justice? Where are the snide comments about the efficiency of the official force? MacDonald is clearly a favorite of Holmes, but the relationship is way too pat, too bland in this story. Give me Lestrade’s stubborn bungling over this milquetoast efficiency any day.
But at least Holmes’ page finally gets a name. Hooray, Billy!

Great commentary, Eddy!
I have also pondered the completely different manner with which Holmes interacts with MacDonald compared with his interactions with Lestrade, Gregson, & company. My belief is that Doyle realized by this time that the Metropolitan Police in general and its Detective Force in particular was made up of fellow human beings, with feelings, who were on the same side as Holmes (and Doyle himself), and felt Holmes needed to treat them more collegially.
By the time _Valley_ was written, Holmes had much fame, and Doyle more celebrity than I think he had dared to imagine. He had long ceased to be an obscure opthamologist at Southsea, and certainly must have, from time to time, had to interact with members of professional police forces.
After all the contempt he voiced for the dectives from The Yard earlier in the canon (wasn’t the nicest thing he had to say about Gregson and Lestrade was that they were “the pick of a bad lot,” after all?), I imagine Doyle decided it best to invent a new detective.
That’s how I saw it.
An interesting point I hadn’t considered. Of course, Doyle then never uses MacDonald again, but as I read forward, it seems he’s trying to soften Holmes’ view of Gregson and Lestrade instead of relying on MacDonald.
Thanks for commenting!