I have several sheets that I am trying to merge together.

Each sheet has a base of the same 6 columns and an unspecified number of
variable columns. I am trying to create a master sheet that will look at all
the other sheets (which have come from other linked sheets) and copy columns
which it hasn't seen before.

Ex.

Base has columns
A B C D
Master has columns
A B C D
Sales and marketing has
A B C D E
Master has
A B C D E
Finance has
A B C E F G
Master has
A B C D E F G

Is this possible? Thanks for any advice!!