The Magic Mountain by Thomas Mann

Young Hans Castorp noticed that the ancestral tremor brought on by his ill-advised walk continued to trouble him -- he found it rather an embarrassment when in the dining-room. Almost as a regular thing now, his head would begin shaking at table; he found this impossible to prevent and hard to dissemble. He tried various devices to disguise the weakness, for he could not continually support his chin on his collar; he would keep his head in action, turning it to the right and left in conversation, or bear hard against the table with the left forearm when he carried a spoonful of soup to his mouth, and support his head with his hand. In the pauses he even rested his elbow on the table, this although it was in his own eyes a piece of ill breeding, which would not pass in any society save the lax abnormal one where he now found himself. But the weakness was burdensome too and went far to spoil the meal hours for him, which he had otherwise continued to find diverting and full of interesting episode.

But the truth was -- and Hans Castorp was entirely aware of it -- that the absurd manifestation against which he struggled was not solely physical in its origin, not wholly to be accounted for by the air up here and the efforts his system made to adjust itself. Rather was it the outward expression of his inner stimulation, and bore directly upon those very episodes and diversions.