COTHERSTONE has come home to the Bowes Museum in Barnard Castle.

A painting of the museum founder’s Derby-winning racehorse, on which he had bets worth £4m in today’s money riding, has been acquired at auction through a bequest left by a former headmistress of Polam Hall School in Darlington.

John Bowes bred Cotherstone at his stud at Streatlam Castle, near Barney, in 1840, and, having named the horse after the Teesdale village, he sent him for training at John Scott’s yard in Malton in Ryedale.

In those days, the sport of kings was notoriously crooked, and although Cotherstone was entered for the Epsom Derby of 1843, his first race in public in late 1842 ended in an unpromising defeat, causing him to drift from 20-1 to rank outside 50-1 for the Derby.

But as 1843 dawned, Cotherstone was transformed. Scott’s brother, Bill, his jockey, said that in training, he was the best colt he had ever ridden. Bowes began to place bets on the outsider to win the Derby, and he increased the security at the training yard in Malton to make sure no one could nobble the horse.

This optimism was confirmed as Cotherstone won his first three races of the season with increasingly impressive performances, and by the morning of the Epsom Derby on May 31, he was the 13-8 favourite among the 23 runners.

They’re off, and jockey Scott kept Cotherstone out of trouble until they hit the front with a quarter-of-a-mile to go, and easily saw off the only challenger, which was believed to be a four-year-old ringer in a race for three-year-olds.

Cotherstone came home two lengths clear and won the £4,250 prize money for Bowes (worth about £550,000 in today’s values, according to the Bank of England Inflation Calculator).

Far more lucratively, Bowes, who was the South Durham MP from 1832 to 1847, had bets worth £30,000 on the horse – that’s £3.9m in today’s values.

As well as his castle and estate in Teesdale, Bowes owned the coal-rich Gibside in north Durham, making him fabulously wealthy, but that afternoon in Epsom, he earned as much from his horses as he did in a year from his land.

The only downside on the day was that the homing pigeons released from Epsom bearing the news of the great victory got lost, and so there were no celebrations in Malton.

Cotherstone won three of his four races in the remainder of 1843, winning a total of £13,790.

The one second place was the St Leger at Doncaster when jockey Scott was injured and a replacement, Frank Butler, took the saddle. Cotherstone led until the final yards when Prizefighter pulled ahead and won by a short head.

There was fury in Cotherstone’s camp, although there was also a very strong suggestion that jockey Butler had “pulled” the horse – stopped him from charging to the line – under the influence of John Gully, of Durham, who had heavily backed Prizefighter.

Gully was a fabulous character. He was a bankrupt butcher from Bath who became a bare knuckle prizefighter and bookmaker to the Prince of Wales. In 1812, he won £40,000 on a single wager and invested the proceeds in Hetton Colliery, to the north-east of Durham city. As his winnings mounted, he sunk more money into Durham pits – Thornley, Wingate, Trimdon – and he lived at Cocken Hall, near Finchale Abbey. His main home, though, was Ackworth Park, near Pontefract, where he was the MP, and he died in another of his properties – 7, North Bailey in Durham – in 1863.

Not, of course, that John Bowes could really complain about underhand tactics on the turf – soon after Cotherstone’s success, he had to lie low in France for more than a year to avoid being prosecuted over an allegedly illegal gambling practice which would have cost him £68,000. Fortunately, while Bowes laid low, his friends in Parliament altered the law so that he could return.

Before the start of the 1844 season, Bowes sold Cotherstone for stud to Lord Spencer, and the horse broke down in his first race at Goodwood and never ran again.

In Cotherstone’s brief career, he had won eight of his 11 races. He was highly regarded as perhaps the best racehorse of the 1840s, but West Australian, who won the 2,000 Guineas, the Derby, the St Leger and the Ascot Gold Cup, in the early 1850s was the best horse Bowes bred at Streatlam.

The Bowes Museum already owns a painting of Cotherstone, but it’s a rather static stable view. The new view has the horse leaping forward with trainer Scott, known as “the wizard of the north”, looking on. It is by the celebrated sporting artist Henry Thomas Alken, and has been acquired thanks to the generosity of the late Margaret Bright, who was headmistress of Polam Hall for a couple of years from 1984.

L With thanks to Jonathan Peacock.