“But, my dear boy,” I interposed, “I think I know rachitis when I see it.”

“So, rachitis is the scientific appellation, eh? Well, in the language of the street, ‘rachitis nothing!’ Can’t you see through a millstone with a hole in it? Doctor, my so-called rickets is nothing more nor less than—”

“Hush! for the Lord’s sake, hush!” I cried, putting my hand over young Smith’s mouth, as a horrible suspicion suddenly flashed upon me. “Be careful, my young friend, even the walls of a doctor’s study may have ears. Can it be possible that I have been mistaken and that—”

“Precisely so, sir,” interrupted my visitor sarcastically. “You are really growing quite intelligent. If you keep on, doctor, you will be as good an intuitive diagnostician as we have in Chicago, and that’s saying much.”

“Yes,” I replied with some confusion, “but you can’t expect a fellow to carry a divining rod about with him, and besides, your family is one of the highest respectability.”

My young visitor sneered perceptibly and retorted:

“Of course, you are like the rest of humanity, looking for respectability in high places and overlooking the pearls that lie imbedded in the mud of poverty and social mediocrity. I really feel inclined to lecture you, doctor, you seem so woefully stupid in some directions. Here you are, with abundant opportunities for study and observation of human nature, maundering of ‘respectability’ as a factor in diagnosis! Not but that it is a factor sometimes, but you don’t weigh the evidence just right. You are inclined to misconstrue social prominence as a factor in your diagnoses. Your interpretation of it is only too often precisely opposite to the truth.

“Look at the childlessness of the average high-toned family—look at the character of the progeny of those who do have children, and then babble of ‘respectability!’ Faugh! doctor, you make me sick. For a scientific physician, you are the most innocent man I ever knew.”

“Oh, come now,” I said, “I don’t pretend to know it all, but I am not quite so big a fool as you might suppose.”

“Well, perhaps not—quite. There may be bigger chumps, but I dare say they are all practicing medicine.”