Question

explain the line,- and in the scowl of heaven each  face grew dark as they were speaking ?
answer the fallowing question from from the poem lord ullin"s daughter

Answer 1

The line 'and in the scowl of heaven each  face grew dark as they were speaking' means it grew dark suddenly as the dark clouds covered the sky; a strong gale began to blow across the loch. Seeing the stormy sea ahead and the angry father along with his fierce men chasing them, Lord Ullin's daughter and her lover grew frightened. They were caught in a dangerous situation. They loch looked threatening with the stormy waves; the angry Lord Ullin was close by to catch hold of them.     

Answer 2

(The lines appear when Lord Ullin's daughter and her lover, Chief of Ulva Isle sat in the boat in stormy sea due to the fear of Lord Ullin and the storm grew stronger.)

The sky was frowning which indicates danger lurking in the form storm and it was worrisome for each person who was speaking and facing the storm.