udacity.

"It's surprising, miss, what funny mistakes them who never leave the
land make about seafaring concerns; but then, what can you expect of
them? they know no better," he added, in a tone showing the deep
commiseration he felt for the ignorance of landsmen. "To say that they
don't know the stem from the stern, isn't to say anything. They know
nothing about a ship, how she's built, how she sails, or what she's
like. The last voyage I made I had a passenger on board who was a
cleverish sort of gentleman, too, and for talking politics he'd go on
for an hour; yet he wanted to know why I couldn't bring the ship to an
anchor right out in the Bay of Biscay; and one night, when it was
blowing a stiffish gale, with a heavy sea running, he roused me out of
my sleep to ask me to send a better hand to the helm; one who knew how
to keep the craft steady, or else to run into some harbour till the
morning. He never could get it out of his head that he was not in the
Thames. Now, miss, I see that you are not one of those sort of people,
and that you will soon know all about a ship, though you may not just
yet be able to act the captain. To-morrow I'll show you how to shoot
the sun, as we tell greenhorns we are doing, when we take an observation
with the quadrant. It's a very pretty instrument, and you will be
pleased to know how to use it."

"I shall like very much to learn all you can teach me, Captain Bowse,"
answered Ada, making a great effort to rouse herself from the feeling of
sadness which oppressed her. "I wonder how mariners managed to
traverse, as they did, the most distant seas, before these instruments
were invented."

"They used to trust more to the sun and stars, and to their lead
reckoning, than they do now, I suppose, miss," answered the master.
"Even now, there's many a man in charge of a vessel who never takes more
than a meridional observation, if even that; and having found his
latitude, runs down the longitude by dead reckoning. Some even go about
to many distant parts entirely by rule of guess, and it is extraordinary
how often they hit their point. Now and then, to be sure, they find
themselves two or three hundred miles out of their course, and sometimes
they get the ship cast away. I have, too, met vessels out in the
Atlantic which had entirely lost their reckoning, and had not the
slightest notion where they were. Once, I remember, when I belonged to
the _Harkaway_ frigate, coming home f