They believed that they had been well grounded back in their High School days.
On their way Darrin's section was passed by three officers of the Navy.

Midshipmen must always salute officers of the Navy.
While marching in sections, however, the only midshipman who salutes is the section leader.
Three times Dave's hand came smartly up to the visor of his cap in salute, while the other men in his section looked straight ahead.
Reaching Academic Hall Dave marched his section mates into the recitation room.
Lieutenant Bradshaw, the instructor, was already present, standing by his desk.
Darrin saluted the lieutenant as soon as he had halted the section.
"Sir, I report all members of the section present." Five of the midshipmen were directed by Lieutenant Bradshaw to go to their seats.

The rest were ordered to blackboards, Dave and Dan among the latter number.
Those at the blackboards were each given a problem to lay out on the blackboard.

Then the instructor turned to the fourth class men who remained in their seats.
These he questioned, in turn, on various aspects of the day's lesson.
All the time the midshipmen at the blackboard worked busily away, each blocking out phase after phase of his problem.
Dave Darrin was first to finish.

He turned his back to the board, taking the position of parade rest.
Dan was third to finish.
"Mr.Darrin, you may explain your work," announced Lieutenant Bradshaw.
This Dave did, slowly, carefully, though without painful hesitation.
When he had finished the instructor asked him several questions about the problem, and about some other phases of the day's work.
Darrin did not jump at any of his answers, but made them thoughtfully.
"Very good, indeed, Mr.Darrin," commented the instructor.