So I am new to Civ; having just recently given the Civ III and IV complete editions bundled together as a gift from a friend. I am learning as I go along and I have just recently started playing Road to War as part of the Beyond the Sword expansion but for the life of me, cannot work out what I have to do research combustion (so that I can build upon inland oil.) I have a couple of units of marines and wish to deploy them on enemy lands across water using landing craft but I am unable to build any landing craft without first acquiring oil. I have a big bubbly puddle of the stuff stuck in the middle of my empire but have no idea how to take advantage of this resource, from what I have read it looks like I need to research combustion but this does not seem to be an option on the research tree thing for this particular mod. Please could somebody point me in the right direction, or inform me of any alternative ways of going about this as I really want to improve my naval power. Thanks, A confused noob.