"But I sometimes shiver over the almost certainty that I'm going to do something just as bad when I get to sea.

If I get sent to the engine room I'll be likely to fill the furnaces with water and the boilers with coal." "Rot!" objected Dan.

"You're not crazy---not even weak-minded." "Or else, if I'm put to navigating, I'm fairly likely to bring the battleship into violent collision with the Chicago Limited, over in Ohio." "Come out of that funk, Davy!" ordered his chum.
"I'm trying to, Danny boy; but there's many an hour when I feel that I haven't learned here all that I should have learned, and that I'll be miles behind the newest ensigns and lieutenants." "There's just about one thing for you to do, then," proposed Dan.
"Resign ?" queried Darrin, looking quizzically at his chum.
"Not by a long sight.

Just go in for a commission as second lieutenant of marines.

You can get that and hold it.