He was still looking at her; and as he quitted her he said, with the indulgence born of his optimism:  “May you keep happy since you are happy.  Happiness must know what it does.”

Nevertheless, Mathieu remained disturbed, as he thought of the apparent injustice of impassive nature.  The memory of his Marianne, struck down by such deep grief, pining away through the impious quarrels of her sons, returned to him.  And as Ambroise at last came in and gayly embraced him, after receiving Celeste’s thanks, he felt a thrill of anguish, for the decisive moment which would save or wreck the family was now at hand.

Indeed, Denis, after inviting himself and Mathieu to lunch, promptly plunged into the subject.

“We are not here for the mere pleasure of lunching with you,” said he; “mamma is ill, did you know it?”

“Ill?” said Ambroise.  “Not seriously ill?”

“Yes, very ill, in danger.  And are you aware that she has been ill like this ever since she came to speak to you about the quarrel between Gregoire and Gervais, when it seems that you treated her very roughly.”

“I treated her roughly?  We simply talked business, and perhaps I spoke to her like a business man, a little bluntly.”

Then Ambroise turned towards Mathieu, who was waiting, pale and silent:  “Is it true, father, that mamma is ill and causes you anxiety?”

And as his father replied with a long affirmative nod, he gave vent to his emotion, even as Denis had done at the works immediately on learning the truth.

“But dash it all,” he said; “this affair is becoming quite idiotic!  In my opinion Gregoire is right and Gervais wrong.  Only I don’t care a fig about that; they must make it up at once, so that poor mamma may not have another moment’s suffering.  But then, why did you shut yourselves up?  Why did you not let us know how grieved you were?  Every one would have reflected and understood things.”

Then, all at once, Ambroise embraced his father with that promptness of decision which he displayed to such happy effect in business as soon as ever a ray of light illumined his mind.

“After all, father,” said he; “you are the cleverest; you understand things and foresee them.  Even if Gregoire were within his rights in bringing an action against Gervais, it would be idiotic for him to do so, because far above any petty private interest, there is the interest of all of us, the interest of the family, which is to remain, united, compact, and unattackable, if it desires to continue invincible.  Our sovereign strength lies in our union—­And so it’s simple enough.  We will lunch as quickly as possible and take the first train.  We shall go, Denis and I, to Chantebled with you.  Peace must be concluded this evening.  I will see to it.”