With the acceleration of industrial growth came acute urban crowding and accompanying social stress--conditions that began to approach disastrous proportions when, in 1888, the first commercially successful electric fraction line was developed.

• 随着工业化的加速发展，城市里出现了严重拥挤和相伴而来的社会压力。 当1888年第一条商业上成功的电气化铁轨被制造出来时，压力开始接近危机的程度。