If you have such a friend as this, your own or your father's, take care to retain him; do not alienate him by negligence or a deficient consideration. Put yourself out of the way to show that you appreciate and value him; do not allow a false reserve or a foolish shyness to check your expression of gratitude. A friendship is a delicate growth; and even when it has become robust, it can easily be blighted. The results of years may be lost in a few days. And if a root of bitterness springs up, if a division occurs, it may be quite impossible by every effort in your power to heal the breach or to pluck up that obstinate root. "A brother offended is harder to be won than a strong city: and such contentions are like the bars of a castle."[485] The closer the intimacy had been, the tenderer the friendship, so much the sterner will be these bars, so much the more inexpugnable the castle. For it will be felt, if such protestations, such interchange of affection, such mutual delights, could have been deceptive, mere hypocrisies or delusions, what hope can there be that the same things broken and patched up again can be of any worth? A difference with a chance acquaintance is easily removed; further knowledge may improve our opinion of one another, and even if we separate we have no deep resentment. But a difference between true friends may quickly become irreparable. They feel that there is no more to know; they have seen the best and that has proved disappointing. The resentment springs from a sense of abused confidence and injured love. If you have real friends then, take pains to keep them. Watch carefully for the small beginnings of a rupture and hasten to heal it. Think no effort is wasted, and no apology or explanation is too humiliating, which may avert that great calamity,--the loss of a true soul-comrade; one whom you have learnt to honour with the name and dignity of friend. "The friends thou hast, and their adoption tried," says our wise poet, "Grapple them to thy soul with hooks of steel."