an?"

Gennaro fumbled in his pocketbook again, and at last drew forth a
typewritten letter bearing the letter-head of the Leslie Laboratories,
Incorporated.

"After I received the first threat," explained Gennaro, "my wife and
I went from our apartments at the hotel to her father's, the banker
Cesare, you know, who lives on Fifth Avenue. I gave the letter to the
Italian Squad of the police. The next morning my father-in-law's butler
noticed something peculiar about the milk. He barely touched some of it
to his tongue, and he has been violently ill ever since. I at once
sent the milk to the laboratory of my friend Doctor Leslie to have it
analysed. This letter shows what the household escaped."

"My dear Gennaro," read Kennedy. "The milk submitted to us for
examination on the 10th inst. has been carefully analysed, and I beg to
hand you herewith the result:

Specific gravity 1.036 at 15 degrees Cent.

Water............................... 84.60 per cent
Casein.............................. 3.49 " "
Albumin............................. .56 " "
Globulin............................ .32 " "
Lactose............................. 5.08 " "
Ash................................. .72 " "
Fat................................. 3.42 " "
Ricin............................... 1.19 " "

"Ricin is a new and little-known poison derived from the shell of the
castor-oil bean. Professor Ehrlich states that one gram of the pure
poison will kill 1,500,000 guinea pigs. Ricin was lately isolated by
Professor Robert, of Rostock, but is seldom found except in an impure
state, though still very deadly. It surpasses strychnine, prussic acid,
and other commonly known drugs. I congratulate you and yours on escaping
and shall of course respect your wishes absolutely regarding keeping
secret this attempt on your life. Believe me,

"Very sincerely yours,

"C. W. LESLIE."

As Kennedy handed the letter back, he remarked significantly: "I can see
very readily why you don't care to have the police figure in your case.
It has got quite beyond ordinary police methods."

"And to-morrow, too, they are going to give another sign of their
power," groaned Gennaro, sinking into the chair before his untasted
food.

"You say you have left your hotel?" inquired Kennedy.

"Yes. My wife insisted that we would be more safely guarded at the
residence of her father, the banker. But