The Adventures of Dr. Thorndyke by R. Austin Freeman
From the writer:
"

The peculiar construction of the first four stories in the present collection will probably strike both reader and critic and seem to call for some explanation, which I accordingly proceed to supply.

In the conventional “detective story” the interest is made to focus on the question, “Who did it?” The identity of the criminal is a secret that is jealously guarded up to the very end of the book, and its disclosure forms the final climax.

This I have always regarded as somewhat of a mistake. In real life, the identity of the criminal is a question of supreme importance for practical reasons; but in fiction, where no such reasons exist, I conceive the interest of the reader to be engaged chiefly by the demonstration of unexpected consequences of simple actions, of unsuspected causal connections, and by the evolution of an ordered train of evidence from a mass of facts apparently incoherent and unrelated. The reader’s curiosity is concerned not so much with the question “Who did it?” as with the question “How was the discovery achieved?” That is to say, the ingenious reader is interested more in the intermediate action than in the ultimate result.

The offer by a popular author of a prize to the reader who should identify the criminal in a certain “detective story,” exhibiting as it did the opposite view, suggested to me an interesting question.

Would it be possible to write a detective story in which from the outset the reader was taken entirely into the author’s confidence, was made an actual witness of the crime and furnished with every fact that could possibly be used in its detection? Would there be any story left when the reader had all the facts? I believed that there would; and as an experiment to test the justice of my belief, I wrote “The Case of Oscar Brodski.” Here the usual conditions are reversed; the reader knows everything, the detective knows nothing, and the interest focuses on the unexpected significance of trivial circumstances.

By excellent judges on both sides of the Atlantic—including the editor of Pearson’s Magazine—this story was so far approved of that I was invited to produce others of the same type.

Three more were written and are here included together with one of the more orthodox character, so that the reader can judge of the respective merits of the two methods of narration.

Nautical readers will observe that I have taken the liberty (for obvious reasons connected with the law of libel) of planting a screw-pile lighthouse on the Girdler Sand in place of the light-vessel. I mention the matter to forestall criticism and save readers the trouble of writing to point out the error."