Mathematical cake cutting from a 1906 Nature Paper

Here is a neat video on how to cut a round cake so you don't end up with those dry sides the next day:

The Scientific Way to Cut a Cake

This is based on a paper by polymath* Francis Galton:
http://galton.org/essays/1900-1911/galton-1906-cake.pdf

My go-to solution is to cover the open sides of the wedge with plastic wrap but I may consider this idea next time I a bake a cake! (Mmmm... cake...) BTW the elastic option only will work well if you are using a fondant icing - it would be very messy with, say, a buttercream icing.

* a polymath is not necessarily someone good at math but someone who has a variety of interests and expertise in different subject areas.