How did railways applied a check on the occurance of famines during the colonial period?

Art the time of british rule the states like Punjab and haryana very very prosperous in the lrge scale production of grains like wheat, rice and other cereals or we can also say that there was extra amount of the food grains as compared to other states. The railways had a main role of the transportation of these surplus amount of grains to the statas who were lagging behind in the production of the same as wll as the famine affected areas of the country. in this way railways applied a check on the occurance of famines.