of the ruin of beleriand and the fall of fingolfin now fingolfin , king of the north , and high king of the noldor , seeing that his people were become numerous and strong , and that the men allied to them were many and valiant , pondered once more an assault upon angband ; for he knew that they lived in danger while the circle of the siege was incomplete , and morgoth was free to labour in his deep mines , devising what evils none could foretell ere he should reveal them .