Stamps & Welding

Before the spread of the Internet, everyone dealt with letters and stamps. One of the pastimes of that time was to separate the stamp from the envelope and keep it. I also had a stamp album when I was a teenager. Therefore, it is not strange that when I started my career as a welding engineer, I looked for the connection between postage stamps and welding.
The file below is the result of that effort.
PS:  Unfortunately, I have not written down the references that I used.

stamps & welding