"Dere iss someding back of id, of course," declared Mr. Schultze.
"_Vas iss?_ Dey are nod being send for our healdh!"

During the next six days half a score of private detectives were at
work on the mystery, with the slender clews at hand. They scanned
hotel registers, quizzed paper-box manufacturers, pestered stamp
clerks, bedeviled postal officials, and the sum total of their
knowledge was negative, save in the fact that they established beyond
question that only these five men had received the diamonds.

And meanwhile the heads of the five greatest jewel houses in New
York were assiduous in their search for that copperplate
superscription in their daily mail. On the morning of the eighth day
it came. Mr. Latham was nervously shuffling his unopened personal
correspondence when he came upon it--a formal white square envelope,
directed by that same copperplate hand which had directed the boxes.
He dropped into his chair, and opened the envelope with eager
fingers. Inside was this letter:

MY DEAR SIR:

One week ago I took the liberty of sending to you, and to each
of four other leading jewelers of this city whose names you
know, a single large diamond of rare cutting and color. Please
accept this as a gift from me, and be good enough to convey my
compliments to the other four gentlemen, and assure them that
theirs, too, were gifts.

Believe me, I had no intention of making a mystery of this. It