"McDowell is at Fredericksburg, with a large Confederate force in his front, and--but let me get a map and show you the situation." He went to a small chest and brought out a map, which he spread on a camp-bed. "Here you see Fredericksburg; McDowell is just south of it. Here, about this point, called Guiney's, is a Confederate division under General Anderson. McClellan has urged Washington to reënforce his right by ordering McDowell to march, thus," describing almost a semicircle which began by going south, then southeast, then southwest; "that would place McDowell on McClellan's right flank, here. Now, if McDowell reënforces McClellan, this entire army cannot cross the Chickahominy, and if McDowell does not reënforce McClellan, this entire army cannot cross the Chickahominy." "Then in neither event can this army take Richmond," said I. "Don't go too fast; I am speaking of movements for the next ten days; afterward, new combinations may be made. In case McDowell comes, it will take ten days for his movement to be completed, and your right wing would move to meet him if need be, rather than move forward and leave him. To move forward would expose McDowell's flank to the Confederates near Guiney's, and it is feared that Jackson is not far from them. Am I clear?" "Yes; it seems clear that our right will not cross; but suppose McDowell does not come." "In that case," said the Doctor, "for McClellan's right to cross the Chickahominy would be absurd, for the reason that a Confederate force, supposed to be from Jackson's army, has nearly reached Hanover Court-House--here--in the rear of your right, if you advance; besides, to cross the Chickahominy with the whole army would endanger your supplies. You see, this Chickahominy River is an awkward thing to cross; if it should rise suddenly, the army on the south side might starve before the men could get rations; all that the Confederates would have to do would be to prevent wagon trains from crossing the bridges. And another thing--defeat, with the river behind the army, would mean destruction. McClellan will not cross his army; he will throw only his left across." "But why should he cross with any at all? It seems to me that with a wing on either side, he would be in very great danger of being beaten in detail."