in Thoreau’s Journal:

It is remarkable how suggestive the slightest drawing is as memento of things seen. For a few years past I have been accustomed to make a rude sketch in my journal, of plants, ice, and various natural phenomena, and though the fullest accompanying description may fail to recall my experience, these rude outline drawings do not fail to carry me back to that time and scene.  It is as if I saw the same things again, and I may again attempt to describe it in words if I choose.