A piece of Wiltshire wit, which consists in sending some raw lad, or simpleton, to a neighbouring farm house, to borrow a horse ladder, in order to get up the horses, to finish a hay-mow.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
Horse Godmother * Horse’s MealNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes