Another mystery of the Elephant 6 universe is Major Organ and the Adding Machine. It was originally a side-project of Jeff Mangum and Julian Koster (both of Neutral Milk Hotel). They released a version of Louis Armstrong's "What a Wonderful World" on Kindercore Records' Christmas in Stereo compilation in 1997. The project grew to include the Elephant Six Orchestra and many others. Known conspirators included Kevin Barnes (Of Montreal), Eric Harris (Olivia Tremor Control), Will Cullen Hart (Circulatory System, Olivia Tremor Control), Andrew Rieger (Elf Power). In March 2001, a CD entitled Major Organ and the Adding Machine was released on Orange Twin Records. The label gives this description of the album:

The Major is a sound poet, instrument builder and complete freak with his teeth out, talking alchemy and eggplants to a dog. The Elephant Six Orchestra is the adding machine, interpreting the Major's "compositions" and instructions to create a world of beards vomiting and birthing. Please Note: this is not Neutral Milk Hotel under another name. This is Aunt Eggma under the name Major Organ under the name the Elephant Six Orchestra who all are under the name Alfred Snouts. Alfred Snouts is the twin attached to the Major, so really this would be a Major Organ album under the name of no one!

Orange Twin's site also features a second bio on this arcane artist, which is simultaneously insightful and bewildering:

What is the Major Organ? Or rather who is this elusive character? Well let me tell you. The "Major" as he is referred to by friends and family resides in a small town just outside of Denver, Colorado. After many years of wandering and travels the Major started to compose his thoughts and dreams onto sheet music. For many years the Major searched for a suitable vehicle to carry out his musical transmissions. Lacking the ability to play these notes on musical instruments, he acquired the help of the Elephant Six Orchestra. Now, for the first time, the Majors' music has been documented on CD. With help from members of Neutral Milk Hotel, The Olivia Tremor Control, Elf Power, Of Montreal, and many other friends, the Major's music has begun to be cataloged. So far The Elephant Six Orchestra has recorded nineteen of his transmissions. Listen as the Major spins his delicious tale of Madam Truffle and her pastry making art (consumed by the town's more tasteful pastry connoisseurs). Rejoice as Francisco the angel comes to release the town's children from their beds (You're free to go, you're free to go!). So take a journey when your mind is not quite fit (and father is away) with the Major and his Orchestra!