A second after he spoke MacIan heard a heavy voice on the other
side of the wall, saying: "I suppose I'd better get over and look
for them. Give me a back."

"Cabby," said MacIan, again assuming the most deliberate and
lingering lowland Scotch intonation, "if ye're really verra
anxious to ken whar a' come fra', I'll tell ye as a verra great
secret. A' come from Scotland. And a'm gaein' to St. Pancras
Station. Open the doors, cabby."

The cabman stared, but laughed. The heavy voice behind the wall
said: "Now then, a better back this time, Mr. Price." And from
the shadow of the wall Turnbull crept out. He had struggled
wildly into his coat (leaving his waistcoat on the pavement), and
he was with a fierce pale face climbing up the cab behind the
cabman. MacIan had no glimmering notion of what he was up to, but
an instinct of discipline, inherited from a hundred men of war,
made him stick to his own part and trust the other man's.

"Open the doors, cabby," he repeated, with something of the
obstinate solemnity of a drunkard, "open the doors. Did ye no
hear me say St. Pancras Station?"

The top of a policeman's helmet appeared above the garden wall.
The cabman did not see it, but he was still suspicious and began:

"Very sorry, sir, but..." and with that the catlike Turnbull tore
him out of his seat and hurled him into the street below, where
he lay suddenly stunned.