Suppose I am enumerating reasons not to fly. Is it then correct to write/say:
Firstly, I prefer the train because I can see the landscape. Secondly, I have control over my luggage, and thirdly, it is better for the environment.
Or is it rather:
First, I prefer the train because I can see the landscape. Second, I have control over my luggage, and third, it is better for the environment.
I thought the first should be correct, but I find the second one in written texts. Which one is correct?