It is recounted that at King's College in the Strand around the time of the war,

It is recounted that at King's College in the Strand around the time of
the war, the Chief of Services would inevitably begin the year's rounds
by teaching "a singularly important principle of medicine." He asked a nurse
to fetch him a sample of Urine. He then talked at length about Diabetes
mellitus. "Diabetes," he said, "is a greek name; but the Romans noticed that
the bees like the urine of diabetics, so they added the word mellitus which
means sweet as honey. Well, as you know, you may find sugar in the urine of
a diabetic ... " By now the nurse had returned with a sample of urine which
the registrar promptly held up like a trophy. We stared at that straw
colored fluid as if we had never seen such a thing before. The registrar
then startled us.

He dipped a finger boldly into the urine, then licked his finger with the
tip of his tongue. As if tasting wine, he opened and closed his lips
rapidly. Could he perhaps detect a faint taste of sugar? The sample was
passed on to us for an opinion. We all dipped a finger into the fluid,
all of us foolishly licked that finger.

"Now," said the Registrar grinning, "You have learned the first principle
of diagnosis. I mean the power of observation." We were baffled. We stood
near the sluice room outside the ward, and in the distance, some anonymous
patient was explosively coughing. "You see," the registrar said continuing
triumphantly, "I dipped my MIDDLE finger into the urine, but licked my
INDEX finger -- not like all you chaps.
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