Never ask for letters of introduction, and be very sparing in your offers to write or accept them.
Seemingly few persons realize that a letter of social introduction is actually a draft for payment on demand. The form might as well be: "The bearer of this has (because of it) the right to demand your interest, your time, your hospitality—liberally and at once, no matter what your inclination may be."
Therefore, it is far better to refuse in the beginning, than to hedge and end by committing the greater error of unwarrantedly inconveniencing a valued friend or acquaintance.
When you have a friend who is going to a city where you have other friends, and you believe that it will be a mutual pleasure for them to meet, a letter of introduction is proper and very easy to write, but sent to a casual acquaintance—no matter how attractive or distinguished the person to be introduced—it is a gross presumption.
The More Formal Note Of Introduction
Dear Mrs. Marks:
Julian Gibbs is going to Buffalo on January tenth to deliver a lecture on his Polar expedition, and I am sending him a card of introduction to you. He is very agreeable personally, and I think that perhaps you and Mr. Marks will enjoy meeting him as much as I know he would enjoy knowing you.
With kindest regards, in which Arthur joins,
If Mr. Norman were introducing one man to another he would give his card to the former, inscribed as follows:
Introducing Julian Gibbs