Riding up to town from Bristol to Bath, and then along the Bath Road, they overtook the postboy in the early hours of January 29th, 1781, driving the mail-cart with the Bristol mails, between Slough and Cranford Bridge, and bidding him "good night," passed him. Arriving at the "Berkeley Arms," Cranford Bridge, they halted for refreshment, and then turned back, with the object of robbing the mail.
George took a piece of black crape from his pocket and covered his face with it; and then they awaited the postboy.
Halting him, George ordered him to alight, and when he meekly did so, seized and bound him, and then flung him into a field. The two then drove and rode off to Windmill Lane, Sion Corner, and thence on to the Uxbridge road, through Ealing, and up Hanger Hill to Causeway Lane. There, in "Farmer Lott's meadow," they rifled the contents of the cart and took the bags bodily away.
Having disposed the mails carefully about their persons, they hurried off on horseback for London, to a house in Orange Street, near Piccadilly, where they were well known. The bags proved to contain between ten and fifteen thousand pounds, in notes and bills.
A clever plan for immediately putting a great part of the notes in circulation was at once agreed upon; and in the space of an hour or two, George left the house fully clothed in a midshipman's uniform, with Joseph following him dressed like a servant. They went to the "White Bear," in Piccadilly, and, hiring a post-chaise, set out upon what was nothing less than a hurried tour of the length and breadth of England; tendering notes at every stage, and taking gold in exchange. By way of Edgeware, they went to Watford, Northampton, Nottingham, Mansfield, Chesterfield, Sheffield, York, Durham, Newcastle, and Carlisle. Thence they returned, on horseback, by way of Penrith, Appleby, Doncaster, Bawtry, and Retford, to Tuxford, where they arrived February 1st. Putting up for a much-needed rest there, with an innkeeper well known to them, they were informed that the Bow Street runners had only that day passed through, in search of them, and had gone towards Lincoln.
Early in the morning, the Westons resumed their express journey, making for Newark, where they were favoured by some exclusive information from an innkeeper friend, which enabled them narrowly to escape the runners, who had doubled back from Lincoln.
Thence, post-haste, they went to Grantham, Stamford, and Huntingdon, to Royston, halting two hours on the way at the lonely old inn known as "Kisby's Hut."
At Ware they took a post-chaise and four, and hurried the remaining twenty miles to London; arriving at the "Red Lion," Bishopsgate, at eleven o'clock on the night of February 2nd. The officers of the law were not remiss in the chase, and were at the "Red Lion" only one hour afterwards.
Once in London, the brothers separated; Joseph taking another post-chaise, and George a hackney-coach. They were traced to London Bridge, but there all track of them vanished.