With a plant press in his backpack, Muir walked more
than 1,000 miles from Kentucky to the Gulf of Mexico,
gathering specimens along the way. His curiosity carried
him farther to California and Alaska, where he tracked
the movements of glaciers
A plant press is a contraption that is used to store samples of plants. The plants are flattened and dried so that they can be transported from one place to another primarily to enable them to be studied.
The specimens that John Muir gathered therefore must have been plants which he then stored in his plant press.
