He used more pacifistic methods in order to help free India from the British raj, or harsh rule (loose translation). Some of these methods would be simple defiance by taking his own salt when there was a law saying that they can't collect their own, or by starving himself for extended periods of time.
This is what I know if you find something better I encourage you to use it, this is at least the basic premise and a few examples.
I hope it helps.
Answer:
trade routes for the first question
The second industrial revolution was said to be between 1870 and 1914, after the civil war[1]. ... The main causes of the second industrial revolution were due to: natural resources, abundant labor supply, strong government policy, new sources of power, railroads and American inventors and inventions.