How does Tarshis develop the idea that during his life, Matthew Henson did not get the credit he deserved ? Use details from the article to support your answer. ^frozen dream, help^

Something there is that doesn't love a wall, that sends the frozen-ground-swell under it, and spills the upper boulders in the sun; and makes gaps even two can pass abreast. the work of hunters is another thing: i have come after them and made repair where they have left not one stone on a stone, but they would have the rabbit out of hiding, to the yelping dogs. the gaps i mean, no one has seen them made or heard them made, but at spring mending-time we find them there. whom does the speaker blame for the gaps in the wall? himself his neighbor nature and hunters rabbits and dogs