When Hannay first meets Blenkiron, it is revealed that he suffers from dyspepsia and so often drinks boiled milk, eats dry toast and fish.
In "Greenmantle", on meeting (Major, at that time) Richard Hannay, he pronounces the word as "Nootral", a dramatic device giving the reader a nice literary clue as to his origin in the USA and dialect.
Hannay has him inspanned as a battalion-commander in British uniform, leading the actions of a scratch American Engineer-company and other emergency troops put together in a hurry.
According to Charles Moore, Blenkiron's presence in Greenmantle is due to the book being written with the purpose of getting the United States to join the Allies in World War I.
He suggests that Buchan "may have felt more comfortable delineating a positive business character as a foreign national who, by reason of his absurd pastiche accent and diction, could not in any case aspire to gentrification.