A is for for Adenoids: The Adenoidal Agatha Christie

"The adenoid...is a mass of lymphatic tissue located behind the nasal cavity...where the nose blends into the throat.....An enlarged adenoid....can obstruct air flow enough so that breathing through the nose can require an uncomfortable amount of work, and inhalation instead occurs through the open mouth.  The enlarged adenoid would also obstruct the nasal airway enough to affect the voice....Enlargement of the adenoid, especially in children, causes an atypical appearance of the face...."
                                                                                             --"Adenoid," Wikipedia

As I mentioned in a recent blog post, I started reading Agatha Christie at the age of eight, going straight to her from L. Frank Baum, so the Queen of Crime was my literary entree into the adult world.  I learned new words and phrases from her, like, as mentioned last time, "old pussies" (in reference to elderly spinsters), as well as "dark horse," "Old sins have long shadows," "The mills of God grind slowly, but they grind exceedingly small," and, most unacceptable today, "There's a n----r in the woodpile."  I also learned from her that most maids back then were named "Gladys" and that they, like girl village shop assistants, almost invariably suffered from adenoids.  Just what were adenoids, anyway?  I had no idea.  I just hoped I didn't have them!

Gladys Martin (Annette Badland)
in a Pocket Full of Rye

The classic adenoidal maid in Christie probably is poor Gladys Martin, found murdered with a clothes peg clipped to her nose in A Pocket Full of Rye (1953):

"Gladys Martin is the parlourmaid or waitress, as they like to call themselves nowadays.  She does the downstairs rooms, lays the table, clears away and helps Crump wait at table.  Quite a decent sort of girl, but very nearly half-witted.  The adenoidal type.

[Inspector] Neele nodded.

"I never even saw [Gladys]," said Pat. 

"Was she a pretty girl?"

"Oh no," said Miss Marple, not at all. Adenoids, and a good many spots.  She was rather pathetically stupid too...."

Recently when I was rereading Christie's Murder Is Easy (1939), in came an adenoidal maid, near the end of the story: One Emily (not Gladys!), house servant to the genteel spinster Miss Honoria Waynfleete, who in some ways is rather a Miss Marpleish sort of character.  Poor Emily is described as "a small, clumsy-looking girl with pronounced adenoids."  Unlike Gladys, who is a rather tragic character meant to be seen with sympathy by the reader (though the blunt descriptions of her failings many will find cruelly repellent today), Emily seems to be played by the author strictly for laughs:

"If you blease, biss, did you bean the frilled billow cases?"

Christie seems directly to relate lack of intelligence with adenoids, when it fact it seems simply a physical malady that could strike anyone.  She recalls in her Autobiography having two regular playmates, Dorothy and Dulcie, "stolid children with adenoids whom I found dull."  Adenoids strike again!

Apparently, though, adenoids can sometimes deceive.  There's maid Beatrice King in the short story "The Lernean Hydra" in The Labors of Hercules  (1947), who appears to Hercule Poirot as

a short, rather sly-looking girl with adenoids.  She presented an appearance of stolid stupidity but her eyes were more intelligent than her manner would have led one to expect.  

Maybe Beatrice King is a dark horse, adenoids notwithstanding.  M. Poirot had better keep his eye on this one!