https://blogs.lib.unc.edu/ncm/2014/01/15/artifact-of-the-month-ice-skates-1860s/
By around the 13th century people
were getting tired of the difficult to control
bone skates and started using a wooden version
with iron blades. There were pros and cons to the
new iron skates. Iron does not have the same oils
that the bone skates had and it tends to be a
little rough. Because of these things, the
coefficient of friction between the iron and the
ice was higher than between the bone and the ice.
The iron was a trade off though, it allowed for
people to change direction and increase speed
using their legs rather than having to hold a
stick or pole to dig into the ice. As time went on
people improved the design of ice skates. They
were given a curved toe that Mayer explained was
likely to prevent tripping on rough ice.
Over time, skates became more common and even more
changes in the design took place. Blades were made
longer and smoother. Smoother blades reduce the
coefficient of friction which allows them to slide
along the ice better. Longer blades spread out the
skater’s weight and kept the blades from making
indents in the ice as much as they had before. As
Knight explains, total frictional force is equal
to normal force times the coefficient of friction.
Longer blades mean less normal force in any one
place. Another notable change in skates over time
was blades being attached to boots, the way they
still are today. The bone and steel skates were
strapped to the outside of shoes. When the blade
is permanently fixed to a boot it allows the
skater to have better control over the angle he or
she applies force to the ice.
