Re: 19th century machining practice

Bob Mcleod

To add a bit to this story, I think it is easy for those of us , used to modern technology and sophistication, to lose sight of the success which earlier Engineers and Railway Builders could achieve with 'primitive' gear.
   Early Railway, and Canal, Surveying is a fine example.
 I find many folk who have forgotten that it is possible to dig a big hole with just a shovel, and we can forget that , in the Machinery Ftting Shop, it is possible to produce remarkably accurate flat or circular surfaces, by the use of little more than a file.  The 'rubbing two sticks together' system..which involves creating two approximately flat, or round, surfaces, by eye, and then offering them to each other, first in one direction, then the other, and marking the high spots.  These are then filed off, and the process repeated, until a near perfect result is obtained.
     In early days in Australia, where local communities needed to be self supporting, it was common for quite small places to have a Foundry and a Blacksmith's shop. Often the operators were barely literate, yet capable of producing first class and imaginative work.
    I have seen broken 6" diameter engine axles, welded together accurately in a forge, with nothing more than a bag of charcoal, a handful of sand, and a couple of good heavy hammers.
  Oh, I could go on..for a lot of this stuff is amazing..
      For those interested in such things...there is a book, 'Beautiful railway Bridge over the Silvery Tay', written by a fellow who teaches Forensic Engineering in Scotland.
    The Tay bridge disaster was the first case in which photographs were taken, for use in the investigation, and these 1870's glass plates were found in the archives. They were so good, that with modern digital methods, they could be magnified to such a  size that the crystalline structure of broken fragments of the bridge could be analysed...and a whole new light thrown on the story.
   It is an intriguing read on 19th century railway building and engineering. It is also a remarkable insight, into how highly capable men can overlook the blindingly obvious!
          Anyone who wants to chat further about such things is welcome to email me direct..
            Cheers,   Bob

[Non-text portions of this message have been removed]

Join to automatically receive all group messages.