Thoreau mostly uses imagery to illustrate time in the excerpt. The second sentence is saying that he is in the midst of time/living, and he can "detect how shallow it is," meaning that he is aware that life is short and that the end is inevitable. Thoreau also describes time as being fleeting, but ever-present.
I hope this helps!
You get home go in the bathroom and u look in the mirror
Pues , that movie was made in honduras, (esa pelicula fue hecha en honduras)
we should interact with nature even if spending time with ourselves is fun
