Page 90 of Ernest Ambler's Notebook
for the Experiment on Dec. 27, 1956

The first entries below the date were made by Ambler. The first of two successful runs began at 12:04 (middle of page). Hudson's notation ``Field on'' (directly under ``Demag II'') refers to the magnetic field produced by the solenoid. An initially high counting rate of β particles (emitted by the cobalt-60 nuclei as polarized by this field) was observed to decrease to the value for randomly oriented nuclei as the polarization decreased because of the gradual warming of the cobalt-60 nuclei (``β counts decrease,'' boxed for emphasis).

After again cooling the crystal and then polarizing the cobalt-60 nuclei in the opposite direction (by reversing the direction of the solenoid current and thus the magnetic-field direction), the NBS physicists observed the opposite behavior of the β-particle counts with time -- the counts gradually increased from an initially low value to the value for randomly oriented nuclei. These two results were what they had been looking for. Hudson later added ``PARITY NOT CONSERVED!'' at the top of the page.