This “take-off” in economic growth occurred because the railroad helped to decrease transportation costs, transport new products and goods to commercial markets, and generally widen the market.
这个在经济增长方面的“腾飞”之所以会出现，是因为铁路帮助降低了交通运输成本，将新的产品和物资运送到商业市场，并普遍地扩大了市场范围。