“You two may go to bed if you like; I am condemned, I see, to a sleepless night.  But before I go to writing, I wish to ask you a few things, Monsieur Plantat.”

M. Plantat bowed in token of assent.

“We must resume our conversation,” continued the detective, “and compare our inferences.  All our lights are not too much to throw a little daylight upon this affair, which is one of the darkest I have ever met with.  The situation is dangerous, and time presses.  On our acuteness depends the fate of several innocent persons, upon whom rest very serious charges.  We have a theory:  but Monsieur Domini also has one, and his, let us confess, is based upon material facts, while ours rests upon very disputable sensations and logic.”

“We have more than sensations,” responded M. Plantat.

“I agree with you,” said the doctor, “but we must prove it.”

“And I will prove it, parbleu,” cried M. Lecoq, eagerly.  “The affair is complicated and difficult—­so much the better.  Eh!  If it were simple, I would go back to Paris instanter, and to-morrow I would send you one of my men.  I leave easy riddles to infants.  What I want is the inexplicable enigmas, so as to unravel it; a struggle, to show my strength; obstacles, to conquer them.”

M. Plantat and the doctor looked steadily at the speaker.  He was as if transfigured.  It was the same yellow-haired and whiskered man, in a long overcoat:  yet the voice, the physiognomy, the very features, had changed.  His eyes shone with the fire of his enthusiasm, his voice was metallic and vibrating, his imperious gesture affirmed the audacity and energy of his resolution.

“If you think, my friends,” pursued he, “that they don’t manufacture detectives like me at so much a year, you are right.  When I was twenty years old, I took service with an astronomer, as his calculator, after a long course of study.  He gave me my breakfasts and seventy francs a month; by means of which I dressed well, and covered I know not how many square feet with figures daily.”

M. Lecoq puffed vigorously at his cigar a moment, casting a curious glance at M. Plantat.  Then he resumed: 

“Well, you may imagine that I wasn’t the happiest of men.  I forgot to mention that I had two little vices:  I loved the women, and I loved play.  All are not perfect.  My salary seemed too small, and while I added up my columns of figures, I was looking about for a way to make a rapid fortune.  There is, indeed, but one means; to appropriate somebody else’s money, shrewdly enough not to be found out.  I thought about it day and night.  My mind was fertile in expedients, and I formed a hundred projects, each more practicable than the others.  I should frighten you if I were to tell you half of what I imagined in those days.  If many thieves of my calibre existed, you’d have to blot the word ‘property’ out of the dictionary.  Precautions, as well as safes, would be useless.  Happily for men of property, criminals are idiots.”