In Mills v. Wyman 20 Mass. 207 (Mass. 1825), a man, far from home, gets ill.  A woman takes him in and gives him medicine.  After he recovers and leaves, he writes her a letter thanking her and promising her $1k.  He doesn't give the money.  In this case, there is no bargained for exchange, and she can't sue.  She gave him a gift, and he makes her a naked promise.  She did not perform the actions in exchange for the $1k. "Past consideration is no consideration."  How is this case different from Hamer v. Sidway?