Thoreau's Journal: 24-Mar-1859
Can you ever be sure that you have heard the very first wood frog in the township croak? Ah! how weather-wise must he be! There is no guessing at the weather with him. He makes the weather in his degree; he encourages it to be mild. The weather, what is it but the temperament of the earth? and he is wholly of the earth, sensitive as its skin in which he lives and of which he is a part. His life relaxes with the thawing ground. He pitches and tunes his voice to chord with the rustling leaves which the March wind has dried. Long before the frost is quite out, he feels the influence of the spring rains and the warmer days. His is the very voice of the weather. He rises and falls like quicksilver in the thermometer.