Google Books now provides a full scan of Angus McDiarmid's Striking and Picturesque Delineations of the Grand, Beautiful, Wonderful, and Interesting Scenery Around Loch-Earn, from which we get the term "incoherent transactions," noted by Kinbote in his note to line 12. It's hilarious, of course, and it seems to relate to PF on a number of fronts:

 

1) The area surveyed by the author is not just Loch Earn, but also the town at one end, Loch-Earn-Head. Awfully similar to Hazel's bus stop isn't it? Here, McDiarmid notes, is a where a man of "incoherent transactions" (a term he uses three times, which seems to relate to theft, a la "pale fire"?) once leapt across a narrow neck of water after stealing a sheep. Hazel, for her part, drowned at Lochan Neck, a narrow place separating Exton from New Wye, where zesty skaters crossed.

 

2) The book contains a "preface," supposedly by a different author, explaining how the manuscript came to be published, and justifying its strange style. Here we might note the familiarity of a number of elements:

 

 

PF: "my friend had a rather coquettish way of pointing out with the tip of his cane various curious natural objects" (168). 

 

We might also think of Hentzner, who guided Shade around his fields, noting "the names of things." But McDiarmid is much more a Kinbotean figure than anything else. Continuing directly from above:

 

"and the amazing pomp of expression in which be clothed his enthusiastic descriptions, rendered Angus himself not the least interesting and romantic object in these 'Alpine solitudes.' Some compliments on his powers of delineation encouraged him to speak of his manuscripts. Little persuasion was necessary to induce him to recite some of the most choice passages, which he did in a manner admirably harmonizing with the matter. As his confidence increased, he began to hint his intentions of publication : and, at last, in the fulness of his heart, he offered, as a mark of peculiar attachment and regard, to entrust the stranger with the manuscripts, on condition that he would send them to the press.

"To give its full value to this mark of confidence, it was accompanied with the assurance that he knew no other person whom he could have trusted so far. ' It was impossible' he said, 'to divine what advantage a designing person might take of such a trust.' And with this becoming caution he had refused, though very earnestly entreated, to give the manuscripts to a gentleman on whom he was somewhat dependent, lest, by publishing them surreptitiously, he might cheat him of his well earned fame."

MR: So here we have a rambling companion who tells tall tales of Alpine lands and becomes himself a kind of Romantic figure, who furthermore discloses his desire to see his accounts published and, though somewhat paranoid, gives them to a stranger (his hunting companion) as a means to seeing them published.  What's more, the accounts, which are here treated with the utmost gravity, turn out to be written in a manner that reveals their author to be a fool (or perhaps the joke is on us!). All of this sounds too familiar.

Finally, the preface anticipates that an authorship question will arise:

"they will probably be inclined to wonder, that an untaught Highlander, whose thoughts have seldom wandered beyond his native mountains, should have been able to express himself in terms of such unparalleled sublimity. So strange, indeed, does this fact appear, that some may be disposed to doubt whether this Angus M'Diarmid be not altogether a fictitious person : and did we choose to be mysterious, it were easy to involve the matter in as much uncertainty as Mr Macpherson has thrown over the divine Poems of Ossian, and thus to encircle ourselves with that radiance of renown, which should beam in its full brightness around the fortunate Author. Let it be our fame(nobis manga satis) to have withstood so powerful a temptation.— Whoever will take the trouble to visit Loch-Earn, a trouble which the scenery will amply repay, may satisfy himself of the real existence of Angus M'Diarmid, and of his being the real author of these Delineations."

Recall that VN often dealt with the question (reversed here) of whether his prefaces were written by fictitious characters. Altogether, I think a case can be made that McDiarmid contributed in some small ways to the formation of Kinbote and perhaps to the storyline in which Kinbote tries to get Shade to write about Zembla. Here is a link to the Google Books scan:

http://books.google.com/books?id=2MUHAAAAQAAJ&printsec=frontcover#PPP7,M1

Matt Roth