nearly one o'clock
in the morning
For a moment Paul looked up from the papers spread out on the table before him -- looked with the preoccupied air of a man who is adding up something in his mind . Then he returned to his occupation . He had been at this work for four hours without a break . It was nearly one o'clock in the morning . Since dinner Karl Steinmetz had consumed no less than five cigars , while he had not spoken five words . These two men , locked in a small room in the middle of the castle of Osterno -- a room with no window , but which gained its light from the clear heaven by a shaft and a skylight on the roof -- locked in thus they had been engaged in the addition of an enormous mass of figures . Each sheet had been carefully annotated and added by Steinmetz , and as each was finished he handed it to his companion .