66 | Great Geologists
Many of the standard procedures employed in modern
geoscience we now take for granted. One of these is
the study of thin-sections, that is to say, small slices of
rock ground to a thickness of 30 microns so that light
can pass through allowing mineral composition to be
determined with the use of a petrographic microscope.
Another is the study of sedimentary structures to assist
in the determination of the depositional environment
of a sedimentary rock. But who first thought of these
techniques? These and many other geological and
scientific innovations came from the work of a brilliant
‘gentleman scientist’ of the Victorian age – Henry Clifton
Sorby.
The advancement of science in the 19th century
was in no small part due to the work of gentlemen of
independent means who were able to set up offices and
research laboratories at home and develop a network
of correspondents (long before the advent of Google
Scholar and email). They harnessed their curiosity for the
natural world and, without being tied to any academic
institution, researched and published prolifically. Some
were gifted polymaths who happily turned their focus of
interest from one branch of science to another as their
curiosity led them. One such person was Sorby whose
achievements in geology were substantial, but who also
published with distinction on a wide range of subjects
including metallurgy, biology and archaeology.
Henry Clifton Sorby photographed in the 1860s.
Photographer unknown. Image courtesy of the University
of Sheffield.
Henry
Clifton Sorby
Sorby was a genuine innovator in geology. It can be said
that he founded petrography through the microscopic
study of thin-sections and sedimentology through the
study of sedimentary structures. He also pioneered
the use of fluid inclusions to understand the formation
and burial history of rocks and minerals. Outside of
geology, he founded the microscopic study of metals
(metallography) that revolutionized the production of
steel, and he created a spectroscopic microscope
to analyse pigments and staining (which also had
applications in forensic science). Most of this work was
carried out at his home in Sheffield where he was based
for his entire career.
The city of Sheffield in England has long been famous
for its metal work, and the Sorby family owned a well-
established tool manufacture business there. Henry
Clifton Sorby was born in 1826. He might have been
expected to run the family business in due course,
but during his schooling he had shown an aptitude for