In perusing the Digest I noticed a reference to whiting that offered
gypsum as the modern name equivalent.  This is an easy enough mistake
to make.

In "Outlines of Industrial Chemistry", by Frank Hall Thorp, Ph.D.
(McMillan, 1916), on page 231 you will find: "Gypsum, terra alba or
mineral white" -- or hydrated calcium sulfate (in 1916 that was
precipitated calcium sulfate).

Listed in the next paragraph is "Whiting, or Paris white, is calcium
carbonate."

So, for the few who actually intend to use _whiting,_ go looking for
traditional "chalk."

Best,
Grant Chapman
West Point, New York