Most middle-class women in the 19th century would have had at least two bonnets, one suitable for summer weather, often made from straw, and one made from heavier fabric for winter wear. Wealthier women would have many bonnets, suitable for different occasions.
As a bonnet developed a peak, it would extend from the entire front of the bonnet, from the chin over the forehead and down the other side of the face. Some styles of bonnets between ca 1817 and 1845 had a large peak which effectively prevented women from looking right or left without turning their heads: a “coal-scuttle” or “poke” bonnet. Others had a wide peak which was angled out to frame the face. In the 1840s it might be crimped at the top to frame the face in a heart shape.