Know the origin of the word horse-trading being used in Indian Politics

In earlier times traders went to Arab countries to purchase horses for their masters, while coming back home some horses died but their master did not believed them. For this reason the traders started cutting tail of dead horses. After some time the traders started developing a feeling of greed and they started purchasing less horses and more tails. This is how the word 'Horse-trading' originated. 
In Indian Politics the word Horse-trading was first used when alliance formation started by purchasing of MLAs and even parties. The one who is successful in purchasing horses is also successful in making a govt.