Both poems are about losing a child, but for two very different reasons.
‘Mother’ is written from the ‘child’s’ perspective although we know it’s not actually a child because the poem is about moving into a home of their own. We know that the child is speaking to the Mother rather than about her because he directly addressed her at the start of the poem. We get an image of the two of them working together, and although he refers to her helping to take measurements around the new house, there is deeper meaning to this, in that it shows the support she has always given and the fact that they are working together shows the depth of the relationship between them. It also has a semantic field of measuring by the mention of span, measure, acres, prairies, spool of tape, length and centimetres.
The second verse begins by saying that ‘you’ (the mother) is at zero end (of the tape) and goes on to give us the idea that the child is unwinding the tape, taking measurements, reporting back to her and then unreeling the tape again. This is metaphoric of the mother being his ‘base’ and him, living his life, returning to her and leaving her again. The unreeling tape is referred to as ‘unreeling years’ which I take to mean the memories that the mother and son hold. This is illustrated further by the use of the words; ‘Anchor. Kite.’ meaning that she is the steady influence and he is young and free.
Conversely, ‘On my first Sonne’ is a tragic account from the father saying good bye to a son who died at a very young age from the plague. This poem opens with the word ‘Farewell’ which shows us that it is directly addressed to his son with an air of sadness. Although we are not told that the boy died the poet refers to the boy’s age (seven) and the fact that he was ‘lent’ to his father as all life could be seen as temporary. Ben Johnson is punishing himself by thinking that he expected too much of his son,