Population explosion

During the 1800's, the industrial revolution saw the advancement of both the railroad and the steam ship. Both inventions lead to exploration and settlement, thus leading to a population growth. Advanced transportation allowed people to travel further distances and discover new lands for settlements. The mass transportation also allowed for the movement of goods such as food, building materials and machinery. During this same time, there were great advancements in medicine and vaccines. What played a bigger part in the population growth, advancement in transportation or medicine.