This scale was later arbitrarily changed when the temperature of boiling water was measured at 212 degrees.
(This scale; was arbitrarily changed; T:when the temperature of boiling water was measured at 212 degrees; T:later) (the temperature of boiling water; was measured; at 212 degrees)
This scale the temperature of boiling water
was arbitrarily changed was measured
T:when the temperature of boiling water was measured at 212 degrees T:later
at 212 degrees