"Horse" joke

A guy walks into a bar and orders a drink. While he is having his drink he sees a larger bottle of money sitting on the bar. So he asks the bartender what the bottle of money is for.
Bartender: "You see that horse over there in the corner?"
Guy: "Sure, I see him"
Bartender: "Well, you put $20 in that big jar there and if you can make the horse laugh you win all the money."
Guy: "Sounds easy. I'll give it a try."
He puts his $20 in the jar, walks over to the horse and whispers something in the horses ear. The horse starts laughing like crazy. The guy comes back picks up his jar of money and leaves.
He comes back into the same bar about a month later and notices another big jar of money on the counter. So once again he asks the bartender what is gong on with the big jar of money.
Bartender: "Well, you remember that horse over in the corner?"
Guy: "Yeah, sure I remember him."
Bartender: "Well, this time you have to put $30 in the jar and you have to make the horse cry."
Guy: "Sounds easy enough, but do you mind if I take the horse outside?"
Bartender: "You can take him outside, but you can't hit him or anything."
Guy: "Not to worry I love animals"
So he takes the horse outside and is not gone 2 minutes and the brings the horse inside and the horse is crying its eyes out. The guy puts the horse back in the corner and grabs his jar of money and gets ready to leave and the Bartender stops him.
Bartender: "Ok, you won the money fair and square, but please tell me, how did you do it?"
Guy: "Well, do you remember the first time when I had to make the horse laugh?"
Bartender: "Yes, what did you say?"
Guy: "I told him I had a bigger penis than him."
Bartender: "Oh, I see, so what did you do to make him cry?"
Guy: " Simple, I showed him!"