Taggett had instantly surmised, the key of Richard's
workshop.

If it had been gold, instead of brass or iron, that bit of metal
would have taken no additional value in Mr. Taggett's eyes. On
leaving Mrs. Spooner's he held it tightly clasped in his fingers
until he reached an unfrequented street, where he halted a moment in
the shadow of a building to inspect the paper, which he had half
forgotten in his satisfaction at having obtained the key. A stifled
cry rose to Mr. Taggett's lips as he glanced over the crumpled
note-sheet.

It contained three lines, hastily scrawled in lead-pencil,
requesting Richard Shackford to call at the house in Welch's Court at
eight o'clock on a certain Tuesday night. The note had been written,
as the date showed, on the day preceding the Tuesday night in
question--the night of the murder!

For a second or two Mr. Taggett stood paralyzed. Ten minutes
afterwards a message in cipher was pulsing along the wires to New
York, and before the sun went down that evening Richard Shackford was
under the surveillance of the police.

The doubtful, unknown ground upon which Mr. Taggett had been
floundering was now firm under his feet,--unexpected ground, but
solid. Meeting Mary Hennessey in the street, on his way to the marble
yard, Mr. Taggett no longer hesitated to accost her, and question her
as to the story she had told William Durgin. The girl's story was
undoubtedly true, and as a piece of circumstantial evidence was only
less important than the elder Shackford's note. The two cousins had
been for years on the worst of terms. At every step Mr. Taggett had
found corroboration of Wollaston's statement to that effect.

"Where were Coroner Whidden's eyes and ears," wrote Mr.
Taggett,--the words were dashed down impatiently on the page, as if
he had sworn a little internally while writing them,--"when he
conducted that inquest! In all my experience there was never a thing
so stupidly managed."

A thorough and immediate examination of Richard Shackford's
private workshop was now so imperative that Mr. Taggett resolved to
make it even if he had to do so under the authority of a
search-warrant. But he desired as yet to avoid publicity.

A secret visit to the studio seemed equally difficult by day and
night. In the former case he was nearly certain to be deranged by the
servants, and in the latter a light in the unoccupied room would
alarm any of the household who might chance to awaken. From the