Dear Terry,

Thanks. This sounds about right regarding the rise of interchangeable 
and interoperable moving parts. Again, the issue that I see as 
crucial is the development of those parts and their use first in 
manufactured objects, second in machines made to manufacture other 
objects. As I understand it, the industrial revolution of the 1770s 
still required fitters to shape and tool the machines one at a time.

This is different to finished goods fitters in the example of car 
doors. This is final adjustment. The cars are made of genuinely 
interchangeable and interoperable parts, and they are in great part 
made by machines and robots that are also industrially manufactured 
and operated by software.

The industrial revolution of the early 1800s involves true 
interchangeable and interoperable parts, first for the manufactured 
objects, later for the machines that made them. We both agree that 
there were earlier mass production systems that made objects, whether 
by eye or by mathematical system or benchmark. The distinction I make 
is both in the objects and the in the system that manufactures them.

Mass manufacturing of artifacts by different kinds of industrial 
molding or mathematical process goes back to the era Klaus noted. 
This involved more than bricks. For example, mass produced Greek 
amphorae were used in the oil and wine trade. Trademarked firmalampen 
lamps were manufactured in the first century AD. (If I'm not 
mistaken, the best selling brand was Stromboli.) As you note, 
ship-building was another example. Vast parts of the great fleets 
must have been mass manufactured -- over 600 Greek ships comprised 
the fleet at Salamis, for example, including more than 200 triremes. 
Surely many ships in the fleet were made to the same template, and 
many more parts in all ships must have fit the same molds for the 
same reason that military allies seek when possible to use the same 
ammunition or replacement parts in equipment.

It's true that path dependency plays a part. But some path dependency 
stories are urban legends. The supposed relation between the width of 
a Roman two-horse chariot and modern railroad gauge is an urban 
legend. You can disprove it easily with a quick look at different 
railroad gauges in the construction of different railroads around the 
world. If early railroad gauges all went back to the same source, 
there would not have been so many standards. (These include three 
different gauges now used in Australia.)

The other issues you raise are interesting and useful. I'm not 
disputing the ideas or facts you raise (other than the Roman horse). 
I emphasize interchangeable working parts as the key factors that 
shaped the modern industrial era. This change began in the early 
1800s, so that's why I use that date. One can easily choose other 
dates for other reasons, and they'd be equally valid in relation to 
the issues you choose to emphasize. It took all of them to get us to 
where we are.

Yours,

Ken


Terry Love wrote:

>May be worth looking at the UK developments in mass production machinery in
>the mid-late 1700s - particularly Manchester and London. Traditionally,
>history books put the start of the industrial revolution in the Midlands but
>Manchester and London quickly became forerunners.
>
>From memory of 'History of Technology' lectures, in the mid to late 1700s
>and early 1800s, interchangeability and interoperability were a secondary
>by-product of manufacturing things more cheaply and more accurately.
>Accuracy was needed for the new mechanisms of textile equipment. Three key
>issues were the ability to measure to less than the eye can see directly;
>the use of drawings that included tolerance  information; and machinery
>capable of cutting geometrically accurate shapes. Underpinning these were
>the use of visual multipliers for measuring such as the vernier and
>different forms of asymmetric levers; along with metal-cutting  machinery
>capable of making accurate screw forms. This latter is credited to Henry
>Maudslay whose machines could measure and machine to 1/10,000 of an inch.
>(see wikis on Henry Maudslay, Joseph Bramah etc).
>
>Perhaps the simplest definition of interchangeable mass manufacturing is
>manufacturing that doesn't require skilled 'fitters': the skilled
>tradespeople  who make the fine changes to products size and fit necessary
>to ensure fuctionality. It's a tempting move, but one that would exclude
>some aspects of current vehicle manufacture, where sub-processes
>occasionally require skilled fitters  - such as final adjustment of car
>doors and choice of precision parts (e.g. pistons and bearings) that are
>separated into size classes rather than being machined accurately to size.
>
>Difficult to get a definition that shapes the answer to circa 1800 as you
>seem to be trying to do. Many mathematically-based Middle Eastern mass
>manufacturing approaches predate as does mass manufacturing of ships.
>
>Perhaps the cleanest is to tie the definition of mass manufacturing to the
>accurate use of four technologies: big cast iron frames, big and long
>shafts, complex mechanisms and systems of feedback control.
>
>As always, path dependency rules (along with the size of roman horse's
>bottoms).
>
>All the best,
>
>Terry