3、With a set of buttons and a loud bell, the device, sold by National Cash Register (NCR), was little more than a simple adding machine.
1、oil adding machine with attached oil meter
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2、Before the adding machine, offices employed dozens of workers who spent all day adding columns of Numbers and double-checking the math of others.
4、The structure, working principle, performances and application of a new type automatic ball-adding machine for ball mill are described, which is designed under the leadership of the author.
