Pronounce it "ott-lottle"

Bob Perkins of BPS Engineering has been interested in atlatl and dart mechanics for decades. BPS engineering claims credit for four major and half a dozen minor discoveries in the field. Onagocag Publishing is pleased to be able to present Mr. Perkins papers on Atlatl mechanics as part of The History and Primitive Technology Page. 


Copyright ©1996 by William R. Perkins


Over 12,000 years ago, hunters tracking the migrating herds of the last ice age across the frozen tundra of what is now the state of Alaska became the first emigrants to enter the North American Continent. These hunter/gatherers brought with them a weapon that reigned supreme among them and their decendants for thousands of years to come, the atlatl. So powerful and effective was the atlatl that scientists and scholars speculate that it, along with the overkill tactics so common to the human race, caused the extinction of the woolly mammoth in North America.

Largely replaced by the bow and arrow around the birth of Christ, it was still being used by some Native Americans during the Age of Discovery, 500 years ago. When Columbus encountered Natives using the atlatl during his voyages to the New World, Europeans who had long forgotten the weapon soon became familiar with it again. These encounters were most certainly with the business end of the weapon, the European wondering "What was that?" just before dying.


The mechanical function of atlatl technology is the flexible dart. The dart can't launch with good accuracy or thrust if it's rigid. Under acceleration by the atlatl, the dart flexes and compresses like a spring, storing energy to be used to push itself away from the atlatl and launching at velocities that easily exceed 100 mph. When you start your swing with a flexible dart, it humps up, like a hissing cat.The dart will flex and at launch point it will recoil and literally jump off the atlatl.

The great innovation of atlatl weights in the evolution of this technology bears the mark of true genius. By superimposing flexibility into the atlatl shaft and applying a mass to influence the amount of flex during the swing, the energy stored in the spring of the atlatl can be exactly matched to that of the dart. This allowed for a more efficient use of the available energies by forcing the atlatl to push the dart away at the same time the dart is pushing away from the atlatl, much like a diver pushing away from a springboard platform.

Over time, different types of atlatl weights were developed to improve upon this effect. One particular type, commonly known as the bannerstone, used ancient "stealth" technology, and went so far as to silence the zip-like noise caused by the swing of the atlatl.

All of these innovations together make the atlatl the impressive weapon it was historically. It's effectiveness can still be dramatically demonstrated today as well.


Click the links below for more of Bob Perkins' atlatl papers.


Atlatl Weights: Function and Classification

Effects of Stone Projectile Points as Mass in the Atlatl and Dart System




 This page was last updated on 07 March 2012.

Copyright © 1998 & 2012 by Wyatt R. Knapp

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