“Thus the first words are ‘Many thanks.’  The first break is at the end of the letter ‘n,’ between it and the ‘y.’  There are three letters before this break.  That stands for the number 3.

“When you come to the end of a word, if the stroke is down at the end of the last letter, that means no break; if it is up, it means a break.  The stroke at the end of the ‘y’ is plainly down.  Therefore there is no break until after the ‘t.’  That gives us the number 2.  So we get 1 next, and again 1, and still again 1; then 5; then 5; then 1; and so on.

“Now, take these numbers in pairs, thus 3-2; 1-1; 1-5; 5-1.  By consulting this table you can arrive at the hidden message.”

He held up a cardboard bearing the following arrangement of the letters of the alphabet: 

   1 2 3 4 5
 1 A B C D E
 2 F G H IJ K
 3 L M N O P
 4 Q R S T U
 5 V W X Y Z

“Thus,” he continued, “3-2 means the third column and second line.  That is ‘H.’  Then 1-1 is ’A ’; 1-5 is ’V ’; 5-1 is ’E’—­and we get the word ‘Have.’”

Not a soul stirred as Kennedy unfolded the cipher.  What was the terrible secret in that scientific essay I had puzzled so unsuccessfully over, the night before?

“Even this can be complicated by choosing a series of fixed numbers to be added to the real numbers over and over again.  Or the order of the alphabet can be changed.  However, we have the straight cipher only to deal with here.”

“And what for Heaven’s sake does it reveal?” asked Saratovsky, leaning forward, forgetful of the fever that was consuming him.

Kennedy pulled out a piece of paper on which he had written the hidden message and read: 

“Have successfully inoculated S. with fever.  Public opinion America would condemn violence.  Think best death should appear natural.  Samarova infected also.  Cook unfortunately took dose in food intended Kharkoff.  Now have three cases.  Shall stop there at present.  Dangerous excite further suspicion health authorities.”

Rapidly I eliminated in my mind the persons mentioned, as Craig read.  Saratovsky of course was not guilty, for the plot had centred about him.  Nor was little Samarova, nor Dr. Kharkoff.  I noted Revalenko and Kazanovitch glaring at each other and hastily tried to decide which I more strongly suspected.

“Will get K.,” continued Kennedy.  “Think bomb perhaps all right.  K. case different from S. No public sentiment.”

“So Kharkoff had been marked for slaughter,” I thought.  Or was “K.”  Kazanovitch?  I regarded Revalenko more closely.  He was suspiciously sullen.

“Must have more money.  Cable ten thousand rubles at once Russian consul-general.  Will advise you plot against Czar as details perfected here.  Expect break up New York band with death of S.”

If Kennedy himself had thrown a bomb or scattered broadcast the contents of the test-tubes, the effect could not have been more startling than his last quiet sentence—­and sentence it was in two senses.