His inventions and innovations included batteries, cement mixer, the sound recording telephone, double- and multi-type cable system, railways used brakes.

他的发明和革新包括蓄电池、水泥搅拌机、录音电话、双工式和多工式电报系统、铁路用制动器等。

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Old age, his inventions and innovations including batteries, cement mixer, sound recording telephone, double - and multi-type cable system, railways used brakes.

晚年，他的发明和革新包括蓄电池、水泥搅拌机、录音电话、双工式和多工式电报系统、铁路用制动器等。

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