In former years many ships were lost in consequence of the masters not knowing their exact position.  In the present day the coast is much better lighted than formerly.  The character of every part of the bottom of the Channel is well-known, so that a ship may grope her way up with the lead going, the mud, sand, or shells, which are brought up sticking to the grease in a little hollow at the end of the lead, showing whereabouts she is.  Then the quadrants, chronometers, and other nautical instruments are of superior construction, and their use better understood; and, lastly, compasses indicate more truly the direction in which the ship is sailing.  Not that compasses themselves are at fault, but that--as papa explained to us--every compass of a ship is influenced by the iron on board the vessel.  Now, before a ship sails she is swung round in all directions, so that the exact amount of the influence exercised by the iron is ascertained, and allowance made accordingly. There are also a large number of careful pilots on the look-out for ships coming up Channel.  However, after a long course of thick weather and contrary winds, the most experienced master is unable to be certain of his true position; and, notwithstanding all the precautions taken, ships are sometimes carried out of their course, or caught on a lee shore, and driven on the rocks and wrecked.  I have been speaking of sailing vessels.  Steamers have an advantage; but even they, from the effects of currents and tides, sometimes get out of their course, or an accident happens to the machinery, or a gale comes on and drives them, in spite of all efforts of paddle or screw, on shore.