You can also find a great deal of work in a chosen field, whether it is the mechanist's trade or bookkeeping.

在某个既定领域，比如机械师或是会计，也可以找到很多工作。

The symbol was force, as a compass-needle or a triangle was force, as the mechanist might prove by losing it, and nothing could be gained by ignoring their value.

符号是力，就像罗盘针或三角形是力一样，机械师可能会通过失去它来证明这一点，而忽略它们的价值将一事无成。