A few years ago, approaching East Langton across the fields from Market Harborough, I came across this pillar. When I got home I did some Googling and discovered why it is there.
The Thoroughbred Heritage website (scroll down as the horse we are interested in is the son of the other Lottery that the page is mostly about) tells the story of Lottery:
As another page on that site says, this monument was erected in 1886, long after Lottery's death, and it is uncertain if it notes an earlier grave for him. But it is known he spent his later years at Astley Grange Farm Stud, East Langton.
In 1839 Lottery won the Grand National (Grand Liverpool), then a race for even weights. In 1840, within the span of a month, he ran six times in steeplechases held in widely separated areas of the country, to which he was walked; all the races were over four miles, and he carried 12-0 in all but one, Cheltenham, where he carried 13 st. - 3 lbs. Of the six races, he won four, at Leamington, Northampton, Cheltenham, and Stratford; the other two were Fakenham and Liverpool, where he fell, as did several other horses, at the stone wall.
A very tough and game horse, his career spanned eight seasons, during which he won five hurdle races and sixteen steeplechases. He was so successful that course clerks wrote rules to specifically cripple him with handicaps, such as at Liverpool in 1841 and 1842, wherein it was specified that the winner of the Cheltenham Steeplechase of 1840 (e.g. Lottery) would be required to carry an additional 18 pounds (in this race was pulled up). At Horncastle the race was "Open to all horses except Mr. Elmore's Lottery."