Washington Rural Heritage librarians recently stumbled upon the genre of photo postcards depicting people (usually children) posed in a small cart, drawn by a unlikely animal (typically a goat). Apparently around the turn of the 20th century into the 1920s, traveling portrait photographers would use a goat cart as a mechanism for soliciting business.
Haystack - A sepia-toned photograph of Evelyn Colgate seated in a child's cart pulled by two goats. She is holding the reins, wearing a straw hat and holding a doll for the journey. She is about 6 years old.
Goat carts in literature! From "Our Animal Friends at Maple Hill Farm," by Alice & Marvin Provensen.
Also not exactly a goat cart, but an odd twist on the goats-and-transportation theme.
ca. 1865, [albumen portrait of a young boy with a goat], J.B. Gibson