A confused reader writes

The Engine Room gets some interesting emails, but this one – from Ms Idowu Opeyemi – has to be my favourite so far:

I'm a Nigerian and a lover of railway system of transportation which is not so effective here in Nigeria. As a result of my passion for it, I decided going on net for information on railway (like I just did today) and stumbled on your blogspot – it was really amazing.

Please, I would like you to do me a favour by updating my mailbox anytime with any information you know/have on railway system of transportation.

To start with, could you please solve this riddle for me? What does a railway uses in running its engine? petrol, diesel or what?

I will be very happy and grateful if you can always be there for me in answering this question and any other one that I may come across later.

Looking forward to a good learning relationship with you.

Ms Opeyemi – I'm sorry if the title of the blog confused you, but here at The Engine Room we are not very knowledgeable about trains. Apus is quite good with motorbikes, we both know a little about trucks and vans, and we'll even try to help you with any language or editing-related queries – but trains, no. Sorry.

If any railway experts out there would like to help Ms Opeyemi, please let me know and I'll put you in touch.