Such is Mr. Proctor's theory of the story, in which I mainly agree.
Mr. Proctor relies on a piece of evidence overlooked by Forster,
and certainly misinterpreted, as I think I can prove to a
certainty, by Mr. Cuming Walters, whose theory of the real conduct
of the plot runs thus: After watching the storm at midnight with
Edwin, Neville left him, and went home: "his way lay in an
opposite direction. Near to the Cathedral Jasper intercepted his
nephew. . . . Edwin may have been already drugged." How the murder
was worked Mr. Cuming Walters does not say, but he introduces at
this point, the two sounds foreheard by Durdles, without explaining
"the howl of a dog." Durdles would hear the cries, and Deputy "had
seen what he could not understand," whatever it was that he saw.
Jasper, not aware of Drood's possession of the ring, takes only his
watch, chain, and pin, which he places on the timbers of the weir,
and in the river, to be picked up by that persistent winter-bather,
Crisparkle of the telescopic and microscopic eyesight.

As to the ring, Mr. Cuming Walters erroneously declares that Mr.
Proctor "ignores" the power of the ring "to hold and drag," and
says that potent passage is "without meaning and must be
disregarded." Proctor, in fact, gives more than three pages to the
meaning of the ring, which "drags" Jasper into the vault, when he
hears of its existence. {3} Next, Mr. Cuming Walters supposes
Datchery to learn from Durdles, whom he is to visit, about the
second hearing of the cry and the dog's howl. Deputy may have seen
Jasper "carrying his burden" (Edwin) "towards the Sapsea vault."
In fact, Jasper probably saved trouble by making the drugged Edwin
walk into that receptacle. "Datchery would not think of the Sapsea
vault unaided." No--unless Datchery was Drood ! "Now Durdles is
useful again. Tapping with his hammer he would find a change . . .