I had several “treasury size” comics in my first collection. The earliest was this extra large reprinting of Detective Comics #27 – the first appearance of the Batman! Unlike my other treasury editions, this one was a hardcover. (I still have it, minus the dust jacket.)
This issue featured my favorite version of the Batman – the original dark vigilante of the night. This issue also included the first installment of “The Mysterious Dr. Fu Manchu”.
Original collection, Current collection