Radish and watercress sandwiches

My grandmother taught me to eat radishes. Or, I should say, I learned the habit from her; I don’t think she had any grand plan to indoctrinate me. She served radishes and scallions with breakfast, accompanied by individual dishes of salt for dipping. My cousin and I, aged about five, theorized implausibly about why the salt improved the flavor of the radish. We could agree only that without salt, the radish tasted impossibly harsh; with it, like heaven. (I may not have been a typical five year old.)