I thought of the letter again.

Craig had lighted a Bunsen burner under a large glass retort.  But he had no sooner done so than he sat down on a chair and, picking up a book which I surmised might be some work on toxicology, started to read.

He seemed not to be able, for the moment, to concentrate his mind and after a little while closed the book and gazed straight ahead of him.  Again I thought of the letter, and the vision that, no doubt, he saw of Elaine making her pathetic appeal for his help.

As he heard my footstep in the hall, it must have recalled him for he snapped the book shut and moved over quickly to the retort.

“Well,” I exclaimed as I entered, “you are the early bird.  Did you have any breakfast?”

I tossed down the letters.  He did not reply.  So I became absorbed in the morning paper.  Still, I did not neglect to watch him covertly out of the corner of my eye.  Quickly he ran over the letters, instead of taking them, one by one, in his usual methodical way.  I quite complimented my own superior acumen.  He selected the dainty note.

A moment Craig looked at it in anticipation, then tore it open eagerly.  I was still watching his face over the top of the paper and was surprised to see that it showed, first, amazement, then pain, as though something had hurt him.

He read it again—­then looked straight ahead, as if in a daze.

“Strange, how much crime there is now,” I commented, looking up from the paper I had pretended reading.

No answer.

“One would think that one master criminal was enough,” I went on.

Still no answer.

He continued to gaze straight ahead at blankness.

“By George,” I exclaimed finally, banging my fist on the table and raising my voice to catch his attention, “you would think we had nothing but criminals nowadays.”

My voice must have startled him.  The usually imperturbable old fellow actually jumped.  Then, as my question did not evidently accord with what was in his mind, he answered at random, “Perhaps--I wonder if—­” and then he stopped, noncommittally.

Suddenly he jumped up, bringing his tightly clenched fist down with a loud clap into the palm of his hand.

“By heaven!” he exclaimed, “I—­I will!”

Startled at his incomprehensible and unusual conduct I did not attempt to pursue the conversation but let him alone as he strode hastily to the telephone.  Almost angrily he seized the receiver and asked for a number.  It was not like Craig and I could not conceal my concern.

“Wh-what’s the matter, Craig?” I blurted out eagerly.

As he waited for the number, he threw the letter over to me.  I took it and read: 

“Professor Craig Kennedy, “The University, The Heights, City.

“Dear Sir,—­

“I have come to the conclusion that your work is a hindrance rather than an assistance in clearing up my father’s death and I hereby beg to state that your services are no longer required.  This is a final decision and I beg that you will not try to see me again regarding the matter.