Describe the schoolmasters appearance, 2 examples from the text. The Adventures of Tom Sawyer

From the text:

The master, throned on high in his great splint-bottom arm-chair, was dozing, lulled by the drowsy hum of study. The interruption roused him.

The master, Mr. Dobbins, had reached middle age with an unsatisfied ambition.

Only the biggest boys, and young ladies of eighteen and twenty, escaped lashing. Mr. Dobbins’ lashings were very vigorous ones, too; for although he carried, under his wig, a perfectly bald and shiny head, he had only reached middle age, and there was no sign of feebleness in his muscle.