there is a reference in the tale of turambar ( p. 88 ) to 'those kindreds about the waters of asgon whence after arose tuor son of peleg ' , but here it is said that tuor did not dwell with his people ( who 'wandered the forests and fells ' ) but 'lived alone about that lake called mithrim [ asgon ] ' , on which he journeyed in a small boat with a prow made like the neck of a swan .