Countdown #93

August 26, 1939

Play Ball!

Countdown #94

Countdown #95

November 2, 1936

Mystic, Magic Rays

Countdown #96

August 1-16, 1936

Berlin, 1936

Countdown #97

#97

Priority of Invention 

Countdown #99

August, 1934

The Franklin Institute

Countdown #100

September 3, 1928 

Black Light Machine

1927 – Prologue

September 7, 1927

Prologue to the Countdown

Before 1927 #5

1905

It's A Quantum Thing

Before 1927 #4

1897 - 1901

Cathode Rays and Radio Waves

Before 1927 #3

1884 - 1879

Spinning Wheels, Vacuums, and Rays

Before 1927 #2

1844 - 1876

Electric Messengers

Before 1927 #1

1824 – 1894

Persistence, Illusions and Dreams