What is in this image? Describe it as if you were explaining it to someone from the 15th century.

This drawing shows a whimsical and delightful scene. It depicts a small, fantastical creature, not unlike the sprites or fairies you might find in folklore, steering a curious, self-moving cart. The cart has no horses or oxen to pull it, yet it moves on its own with round objects beneath it, which serve as its wheels. Within this contraption, the creature is transporting a large evergreen tree, decorated with circular patterns that may suggest festive adornments, akin to the way one might beautify a Yule log or a Maypole. The doors of the cart are glassless, making it easy to see inside, an inventive feature that allows the creature to be seen clearly. The scene is lively yet simple, melding both the fantastical and the mechanical in a manner that would intrigue any observer from your century.