In mending wall, what is most likely the author’s intent in the following lines to describe boulders? and some are loaves and some so nearly balls we have to use a spell to make them balance

the answer is: the start of world war i, and russia’s hopes of benefiting from it

during world war i russian joined due to in their current crisis they were being supported by france and the war was already declared to them by germany, they needed to maintain their political goal and leadership role in the balkans, and is the same feeling that this excerpt evoke the eager of maintain the land value.