The human heart is like india-rubber; a little swells it$$$ but a great deal will not burst it. If "little more than nothing will disturb it$$$ little less than all things will suffice" to break it. As in the outer members of our frame$$$ there is a vital power inherent in itself that strengthens it against external violence. Every blow that shakes it will serve to harden it against a future stroke; as constant labour thickens the skin of the hand$$$ and strengthens its muscles instead of wasting them away: so that a day of arduous toil$$$ that might excoriate a lady's palm$$$ would make no sensible impression on that of a hardy ploughman.