10: Standardization of Products

A significant advantage to tools and machines in manufacturing is the standardization of products. Once a machine is set, it turns out many parts that are perfectly identical.

Babbage mentions the example of jewelry boxes. When crafted by hand, the lid of one box is tailored to fit that box perfectly, but if the lid is damaged, a new one must be made for that specific box. When crafted by machine, the size of boxes and lids is perfectly uniform, such that the lids of multiple boxes can be swapped, or if a lid is damaged any other will serve as a spare and will fit perfectly. This cannot be done by hand with speed and efficiency.

The industrial application of standardized components is even more significant. Consider that a watch is made of many small gears that must be tooled and adjusted to mesh with one another perfectly. But if the gears are made in a mechanized manner, entire bins of gears can be turned out efficiently and a watch can be assembled by unskilled laborers. And again, should the watch ever be damaged, repair is merely a matter of replacing one part with another.

Something as simple as a threaded metal pipe is also impossible to make by hand. The most skilled blacksmith cannot manage to make a pipe that is perfectly straight and perfectly uniform in thickness, and to cut grooves that are perfectly aligned at the ends. But a machine can turn out pipes that are perfect in these regards, and perfectly identical across a large number of units.

(EN: Many of the advances in the use of interchangeable parts were being demonstrated around the time this book was written. In the present day it is so common that we hardly take notice - but at the time it was a wondrous development.)