From that report we take the following particulars.

On arriving at Vienna, he had three private interviews with the Archduke Albrecht, and set before him the desirability of a joint invasion of North Germany in the autumn of that year.

To this the Archduke demurred, on the ground that such a campaign ought to begin in the spring if the full fruits of victory were to be gathered in before the short days came.

Austria and Italy, he said, could not place adequate forces in the field in less than six weeks owing to lack of railways[15].
[15] _Souvenirs militaires_, by General B.L.J.Lebrun (Paris 1895), pp.
95-148.
Developing his own views, the Archduke then suggested that it would be desirable for France to undertake the war against North Germany not later than the middle of March 1871, Austria and Italy at the same time beginning their mobilisations, though not declaring war until their armies were ready at the end of six weeks.

Two French armies should in the meantime cross the Rhine in order to sever the South Germans from the Confederation of the North, one of them marching towards Nuremberg, where it would be joined by the western army of Austria and the Italian forces sent through Tyrol.