When the hostile army drew near to the town, the courage of some of the leading men failed, and they went out to seek terms of peace. They promised to do whatever was commanded, and they gave hostages, but on their return they found their negotiations disavowed and the city determined to stand a siege. This lasted only eighteen days. Some decided advantage which the Normans gained--the undermining of the walls seems to be implied--induced the city to try again for terms. The clergy, with their sacred books and relics, accompanied the deputation, which obtained from the king better promises than had been hoped for. For some reason William departed from his usual custom of severity to those who resisted. He overlooked their evil conduct, ordered no confiscations, and even stationed guards in the gates to keep out the soldiers who would have helped themselves to the property of the citizens with some violence. But as usual he selected a site for a castle within the walls, and left a force of chosen knights under faithful command, to complete the fortification and to form the garrison. Harold's mother, Gytha, left the city before its surrender, and finally found a refuge in Saint Omer, in Flanders. Harold's sons also, if they were in Exeter, made their escape before its fall. After subduing Exeter, William marched with his army into Cornwall, and put down without difficulty whatever resistance he found there. The confiscation of forfeited estates was no doubt one object of his march through the land, and the greater part of these were bestowed upon his own half brother, Robert, Count of Mortain, the beginning of what grew ultimately into the great earldom of Cornwall. In all, the grants which were made to Robert have been estimated at 797 manors, the largest made to any one as the result of the Conquest. Of these, 248 manors were in Cornwall, practically the whole shire; 75 in Dorset, and 49 in Devonshire. This was almost a principality in itself, and is alone nearly enough to disprove the policy attributed to William of scattering about the country the great estates which he granted. So powerful a possession was the earldom which was founded upon this grant that after a time the policy which had been followed in Normandy, in regard to the great counties, seemed the only wise one in this case also, and it was not allowed to pass out of the immediate family of the king until in the fourteenth century it was made into a provision for the king's eldest son, as it has ever since remained. These things done, William disbanded his army and returned to spend Easter at Winchester.