The metallograph displayed in ASM International’s lower lobby turns 100-years old this year! Presented to ASM by the Wisconsin Electric Power Company (now We Energies), the 1921 Bausch & Lomb photometallograph could magnify samples about 1500 times. While no longer in use, the instrument serves as a testament to the ingenuity of 19th century scientists as well as the advancement of technology through the last century.
Henry Clifton Sorby is credited as the “Father of Metallography” in part due to his work using microstructures to illuminate how carbon content in steel affects strength. In his lifetime, Sorby would see the impact microscopes would make, noting “In those early days, if a railway accident had occurred and I had suggested that the company should take up a rail and have it examined with the microscope, I would have been looked upon as a fit man to send to an asylum. But that is what is now being done.” Metallography would continue to grow, needing faster microscopes along with it.
Though the instruments look much different today, the 1921 metallograph is still as recognizable as the reflected light microscopes across ASM’s lobby in the microscopy lab. Modern scopes follow the same optical principles as their predecessors, so advancements are evident by the additions of computers and other technology.
Looking at the image of the metallograph, the wooden box seen on the right is the camera, today replaced by a digital camera. To the left are the vertical illuminator and eyepieces with a stage. The newer scopes house the optical pathway, can quickly change over increasingly magnified objectives, and can be equipped with an automatic stage. The circular pane to the right of the vertical illuminator is an aperture. The arc used for light are now commonly halogen or LED lights.
Though modern microscopes are much smaller and faster than the vintage Bausch & Lomb, it remains a celebrated piece of history.
-Contributed by Hallie Chavez, ASM Lab Technician
Image – The 1921 Bausch & Lomb photometallograph stands in the lower lobby at ASM International headquarters.
