truth was revealed to me at Ostrog.

CHAPTER XIII

OUR WIRELESS SECRETS

Something important was being attempted, but what it was neither Ray
Raymond nor myself could make out.

We had exerted a good deal of vigilance and kept constant watch upon
Hartmann's house in Pont Street since my return from Poland, but all to
no purpose.

Vera had been staying in London with her aunt and had greatly assisted
us in keeping observation upon two strangers who had arrived in London
about a month ago, and who were staying in an obscure hotel near
Victoria Station.

Their names were Paul Dubois, a Belgian, and Frederick Gessner, a
German. The first-named was, we judged, about forty, stout,
flabby-faced, wearing gold pince-nez, while the German was somewhat
younger, both quiet, studious-looking men who seemed, however, to be
welcomed by many of the prominent members of the German colony in
London.

On five separate occasions we had followed the pair to King's Cross
Station and watched them take third class tickets to Hull. They would
remain there perhaps two or three days, and then return to London.

After a while they had grown tired of their hotel, and had taken a small
furnished house at the top of Sydenham Hill, close to the Crystal
Palace, a pleasant little place with a small secluded garden in which
were several high old elms. They engaged a rather obese old Frenchwoman
as housekeeper, and there they led a quiet life, engrossed apparently in
literary studies.

I confess that when it came my turn to watch them I became more than
ever convinced that Raymond's suspicions were ungrounded. They seldom
went out, and when they did, it was either to dine with Hartmann, or to
stroll about the suburban roads of Norwood, Sydenham, and Penge.

Late one afternoon, however, while I was down at Sydenham, I saw them
emerge from the house, carrying their small suit-cases, and followed
them to King's Cross Station, where they took tickets for Hull.

Instantly I rushed to the telephone and informed Ray in Bruton Street of
my intention to follow them.

That same night I found myself in the smoke-grimed Station Hotel in
Hull, where the two foreigners had also put up.

Next day they called at a solicitor's office at the end of
Whitefriargate, and thence, accompanied by a man who was apparently the
lawyer's managing clerk, they went in a cab along the Docks, where, at a
spot close to the Queen's Dock, they pulled up before an