Both Mr.Campbell and his clerk were quite ready to swear that they had had an interview concerning some diamond earrings with a lady, of whose identity with the accused they were perfectly convinced, and to the casual observer the question as to the time or even the day when that interview took place could make but little difference in the ultimate issue.
"Now I took in, in a moment, the entire drift of Sir James Fenwick's defence of Edith Crawford.

When Mr.Macfarlane left the witness-box, the second victim of the eminent advocate's caustic tongue, I could read as in a book the whole history of that crime, its investigation, and the mistakes made by the police first and the Public Prosecutor afterwards.
"Sir James Fenwick knew them, too, of course, and he placed a finger upon each one, demolishing--like a child who blows upon a house of cards--the entire scaffolding erected by the prosecution.
"Mr.Campbell's and Mr.Macfarlane's identification of the accused with the lady who, on some date--admitted to be uncertain--had tried to sell a pair of diamond earrings, was the first point.

Sir James had plenty of witnesses to prove that on the 25th, the day after the murder, the accused was in London, whilst, the day before, Mr.Campbell's shop had been closed long before the family circle had seen the last of Lady Donaldson.

Clearly the jeweller and his clerk must have seen some other lady, whom their vivid imagination had pictured as being identical with the accused.
"Then came the great question of time.

Mr.David Graham had been evidently the last to see Lady Donaldson alive.