## Book Review: Proving Ground, Kathy Kleiman

Proving Ground is a fascinating book about the 6 women who programmed the first programmable computer, the ENIAC (Electronic Numerical Integrator And Computer).  Prior to this, the women were computers as the term was used in the 1940s for people who sat in front of calculating machines and performed lengthy numerical computations solving differential equations to find the path of an artillery shell one bloody addition/subtraction/multiplication/division at a time.  When World War II started and when the man were off in the army, the search was on for  women with a mathematical background who could do this.

A single trajectory took a day to calculate, and each trajectory had to be separately calculated for different wind currents, air temperature, speed and weight of the shell.  The computations were largely done at the Moore School of Engineering at Penn and were way too slow (although accurate) to produce the numbers of trajectories the army needed.

Enter Dr. John Mauchley who had an idea of how to do this using vacuum tubes, and a brilliant 23 year old engineer, J. Presper Eckert, who could instantiate it. The army committed money to building the machine, which came in 42 monster boxes 8 feet tall, 2 feet wide and what looks like 4 feet deep.

6 of the best and brightest computers of trajectories were recruited to figure out how to wire the boxes together to mimic the trajectory calculations they had already been doing.  So, if you’ve ever done any programming, you’ll know that having a definite target to mimic with software makes life much easier.

Going a bit deeper, if you’ve done any programming in machine language, you know about registers, the addition and logical unit, hard wired memory, alterable memory.

Here’s what the 6 women were given by Dr. Eckert (without ever seeing the monster boxes)

l. A circuit diagram of each box, showing how this vacuum tube activated that vacuum tube etc. etc. The 42 boxes contained 18,000 vacuum tubes.  Vacuum tubes and transistors are similar in that their utility is that they only conduct electricity in one direction and can be turned on and off.

2. A block diagram — which showed how the functions of a unit or system interrelate

3. A logical diagram — places for dials switches, plug and cables on the front of the 42 units.

So given this, the 6 had to figure out what each unit did, and how to wire them together to mimic the trajectory calculations they had been doing.

They did it, and initially without being able to enter the room with the boxes (because they didn’t have the proper security clearance).  Eventually they got it and were able to figure out how to wire the boxes together.

If that isn’t brilliant enough, because the calculations were still taking too long, they invented parallel programing.

For those of you who know computing, that should be enough to make you thirst for more detail.

The book contains a lot of sociology.  The women were treated like dirt by the higher ups (but not by Mauchley or Eckert).  When the time came to show ENIAC off to the brass (both academic and military), they were tasked with serving coffee and hanging up coats.  When Kleiman found pictures of them with ENIAC and asked who they were, she was told they were ‘refrigerator ladies’ — whose function was similar to the barely clothed models draped over high powered automobiles to sell them.

I’ll skip the book’s sociology for some sociology of my own.  The book has biographies and much fascinating detail about all 6 women.  I grew up near Philly, and know the buildings at Penn where this was done (I went to Penn Med). Two of the 6 were graduates of Chestnut Hill College, a small Catholic school west of Philly.  The girl across the street went there.  Her mother was born in County Donegal and cleaned houses.  Her father dropped out of high school at 16 to support his widowed mother.  No social services between the two world wars, wasn’t that terrible etc. etc.  Her father worked in a lumberyard, yet the two of them sent both children to college, and owned their own home (eventually free of debt).  The Chestnut Hill grad I know became an editor at Harcourt Brace, her brother became a millionaire insurance executive.  It would be impossible for two working class people to do this today where I grew up (or probably in most places).