So your clue here was the name of the racehorse, Aristotle. Who seems hard to track down.
The real Aristotle was Greek, and it seems that his father was physician to the King, Amyntas His father delighted in sharing his knowledge with his son and fairly early on Aristotle went to Athens and became a pupil of Plato. After that he spent some time teaching - and one of his pupils was Alexander the Great.
He spent his entire life mastering of many sciences, including the physics that we have just seen demonstrated by football, but also the life sciences of biology and zoology, and the earth sciences of geology and meteorology. And he is still referred to as"The Father of Western Logic".
This is one of three sets called "Derby Entrants" issued in different years, namely 1926, 1928 and 1929. Anyone know why there was no 1927 ? I thought maybe it did not take place, but it did, on Wednesday 1st June.
In our original Ogdens Reference Book, RB.15, issued in 1949, the three sets are listed and coded separately. This is understandable because without looking at the back title you would definitely think them completely different sets. The first one, 1926, is a set of twenty-five cards in colour, and shows the horse as the main picture and the owners colours as an inset. The second one, 1928, is a set of fifty cards in colour but only shows the horse, and our set is described in that book as "Series of 50. Fronts in sepia, horses, some with jockeys up".
Our original World Tobacco Issues Index splits them up as well, but summarises the above into simply "Sm, Sepia. Nd. (50)" - and the updated version is identical, save a new code.