Stargirl Wiki
Stargirl Wiki

Rex Tyler's Journal is a black journal that was written by the late Rex Tyler. It contains formulas and diary entries.


Inscribed with his name on the cover, Rex Tyler began penning this journal during his earliest days of becoming Hourman and possibly before when he invented his signature tool, the Hourglass. A brilliant chemist, he jotted down complicated chemical formulae and other mathematical probabilities. He also used the journal as a diary and wrote a slew of diary entries. Before Rex and Wendi Tyler were killed, Rex packed his journal and JSA files into an envelope which promptly mailed from Blue Valley to Pat Dugan who lived in California at the time.[1] Pat Dugan suspected that his friend's formulae could be hidden codes but was never able to decipher any meaning behind the numbers.


Pat handed the journal to Rex's son Rick after he took up his father's mantle as Hourman. Pat hoped that Rick could crack the equations or see something in them that he didn't. It was only then that Rick was able to determine that the diary entries themselves had incorrect information. He pondered if the diary entries could also be some sort of code along with the equations. He took the journal to Beth Chapel, who looked at the equations using her goggles but came up short on answers.[2]

Rick continued to study the journal in the hopes of solving the equations, even furthering his chemistry education.


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Notes and Trivia

  • Dr. Mid-Nite's goggles were unable to determine the equations inside the journal.[2]
  • Rex wrote about growing up in Michigan, despite having grown up in Connecticut. He also stated that he met Wendi Tyler at Calvin College, even though they met when they were children.[2]