certainly
not Durban. The stamp was a Cape Colony one, and of the mark I could
only read three letters, T. R. S. This was no sort of clue, and I
turned the thing over, completely baffled. Then I noticed that there
was no mark of the post town of delivery. Our letters to
Blaauwildebeestefontein came through Pietersdorp and bore that mark. I
compared the envelope with others. They all had a circle, and
'Pietersdorp' in broad black letters. But this envelope had nothing
except the stamp.

I was still slow at detective work, and it was some minutes before the
explanation flashed on me. The letter had never been posted at all.
The stamp was a fake, and had been borrowed from an old envelope.
There was only one way in which it could have come. It must have been
put in the letter-bag while the postman was on his way from
Pietersdorp. My unknown friend must therefore be somewhere within
eighty miles of me. I hurried off to look for the post-runner, but he
had started back an hour before. There was nothing for it but to wait
on the coming of the unknown.

That afternoon I again took Mr Wardlaw for a walk. It is an ingrained
habit of mine that I never tell anyone more of a business than is
practically necessary. For months I had kept all my knowledge to
myself, and breathed not a word to a soul. But I thought it my duty to
tell Wardlaw about the letter, to let him see that we were not
forgotten. I am afraid it did not encourage his mind. Occult messages
seemed to him only the last proof of a deadly danger encompassing us,
and I could not shake his opinion.

We took the same road to the crown of the Berg, and I was confirmed in
my suspicion that the woods were empty and the watchers gone. The
place was as deserted as the bush at Umvelos'. When we reached the
summit about sunset we waited anxiously for the sound of drums. It
came, as we expected, louder and more menacing than before. Wardlaw
stood pinching my arm as the great tattoo swept down the escarpment,
and died away in the far mountains beyond the Olifants, Yet it no
longer seemed to be a wall of sound, shutting us out from our kindred
in the West. A message had pierced the wall. If the blesbok were
changing ground, I believed that the hunters were calling out their
hounds and getting ready for the chase.

[1] A species of buck.

CHAPTER VII

CAPTAIN ARCOLL TELLS A TALE

It froze in the night, harder than was common on the Berg even in