Final answer:
Upon scanning the lines provided, the first line is in iambic pentameter, while the second and third lines are in iambic tetrameter, with each demonstrating unstressed-stressed syllabic patterns.
Step-by-step explanation:
The meter of each line of poetry can be determined by analyzing the arrangement of stressed and unstressed syllables in a line. To do this, we look at the rhythmical pattern, or meter, to find the regular pattern.
For the line "because their words had forked no lightning they", if we scan this line, we find that it consists of five feet of unstressed and stressed syllables (iambic). Each foot, known as an iamb, thus makes it an iambic pentameter.
The line "a lonely impulse of delight" contains four feet which if scanned, seems to be made of unstressed-stressed syllables, making it an iambic tetrameter due to its four feet of iambs.
Upon examining "no likely end could bring them loss", we can find four feet as well. Since our assumption is that the lines are regularly metered, this too would be considered an iambic tetrameter, with the pattern being unstressed then stressed syllables.