Go with me to the great river Mississippi. It is the longest river in the world. A line that would measure it would just reach to the centre of the earth, -in other words, it is four thousand miles in length. Go with me to this majestic river. I do not wish you to travel to its source; only as far up as Point Coup e, about three hundred miles from its mouth. There we shall stop for a while-a very short while-for we have a long journey to make. Our...