I.

When the time-gun boomed from Edinburgh Castle, Bobby gave a startled yelp.  He was only a little country dog—­the very youngest and smallest and shaggiest of Skye terriers—­bred on a heathery slope of the Pentland hills, where the loudest sound was the bark of a collie or the tinkle of a sheep-bell.  That morning he had come to the weekly market with Auld Jock, a farm laborer, and the Grassmarket of the Scottish capital lay in the narrow valley at the southern base of Castle Crag.  Two hundred feet above it the time-gun was mounted in the half-moon battery on an overhanging, crescent-shaped ledge of rock.  In any part of the city the report of the one-o’clock gun was sufficiently alarming, but in the Grassmarket it was an earth-rending explosion directly overhead.  It needed to be heard but once there to be registered on even a little dog’s brain.  Bobby had heard it many times, and he never failed to yelp a sharp protest at the outrage to his ears; but, as the gunshot was always followed by a certain happy event, it started in his active little mind a train of pleasant associations.

In Bobby’s day of youth, and that was in 1858, when Queen Victoria was a happy wife and mother, with all her bairns about her knees in Windsor or Balmoral, the Grassmarket of Edinburgh was still a bit of the Middle Ages, as picturesquely decaying and Gothic as German Nuremberg.  Beside the classic corn exchange, it had no modern buildings.  North and south, along its greatest length, the sunken quadrangle was faced by tall, old, timber-fronted houses of stone, plastered like swallows’ nests to the rocky slopes behind them.

Across the eastern end, where the valley suddenly narrowed to the ravine-like street of the Cowgate, the market was spanned by the lofty, crowded arches of George IV Bridge.  This high-hung, viaduct thoroughfare, that carried a double line of buildings within its parapet, leaped the gorge, from the tall, old, Gothic rookeries on High Street ridge, just below the Castle esplanade.  It cleared the roofs of the tallest, oldest houses that swarmed up the steep banks from the Cowgate, and ran on, by easy descent, to the main gateway of Greyfriars kirkyard at the lower top of the southern rise.

Greyfriars’ two kirks formed together, under one continuous roof, a long, low, buttressed building without tower or spire.  The new kirk was of Queen Anne’s day, but the old kirk was built before ever the Pilgrims set sail for America.  It had been but one of several sacred buildings, set in a monastery garden that sloped pleasantly to the open valley of the Grassmarket, and looked up the Castle heights unhindered.  In Bobby’s day this garden had shrunk to a long, narrow, high-piled burying-ground, that extended from the rear of the line of buildings that fronted on the market, up the slope, across the hilltop, and to where the land began to fall away again, down the Burghmuir.  From the Grassmarket,