I think he is offering you a very fair test.

I must tell you plainly that if you don't produce the letters you say you possess, I shall regret having put myself forward in this matter at all." "Gently, sir," said the Colonel; "she has not refused to produce them." Lucy put her hand in her pocket and drew out a packet of letters, but she hesitated, and looked timidly at Monckton, after his late severity.

"Am I bound to part with them ?" "Certainly not," said Monckton, "but you can surely trust them for a minute to such a man as Colonel Clifford.

I am of opinion," said he, "that since you can not be confronted with this gentleman's son (though that is no fault of yours), these letters (by-the-bye, it would have been as well to show to me,) ought now at once to be submitted to Colonel Clifford, that he may examine both the contents and the handwriting; then he will know whether it is his son or not; and probably as you are fair with him he will be fair with you and tell you the truth." Colonel Clifford took the letters and ran his eye hastily over two or three; they were filled with the ardent protestations of youth, and a love that evidently looked toward matrimony, and they were written and signed in a handwriting he knew as well as his own.
He said, solemnly, "These letters are written and were sent to Miss Lucy Muller by my son, Walter Clifford." Then, almost for the first time in his life, he broke down, and said, "God forgive him; God help him and me.
The honor of the Cliffords is an empty sound." Lucy Monckton rose from her chair in genuine agitation.

Her better angel tugged at her heartstrings.
"Forgive me, sir, oh, forgive me!" she cried, bursting into tears.