function sellAndBurnMln(uint mlnAmount) external {
        require(registry.isFund(msg.sender), "Only funds can use the engine");
        require(
            mlnToken().transferFrom(msg.sender, address(this), mlnAmount),
            "MLN transferFrom failed"
        );
        uint ethToSend = ethPayoutForMlnAmount(mlnAmount);
        require(ethToSend > 0, "No ether to pay out");
        require(liquidEther >= ethToSend, "Not enough liquid ether to send");
        liquidEther = sub(liquidEther, ethToSend);
        totalMlnBurned = add(totalMlnBurned, mlnAmount);
        msg.sender.transfer(ethToSend);
        mlnToken().burn(mlnAmount);
        emit Burn(mlnAmount);
    }