"...test it first and state the rule
afterward".LEONARDO Da Vinci:(b. 1452.
d.1519)
Battle machines, bows and ballistics
Some of Leonardo's archery related notes and drawings,
by Hilary Greenland
A TV programme in early 2003, where two of Leonardo's most
famous designs were recreated, reminded me of an article I wrote for the
US magazine 'Instictive archer' (sadly now defunct). I researched the great
man's investigations into archery and associated subject in general, and
it is no surprise that such a prolific genius should have been fascinated
by the subject. The designs involved in the TV feature were:
1. a glider based on a bird's wing where Leonardo's designs were very closely
followed and which was a success when tested
2. the giant 'crossbow', where modern structural engineering theory led
to a departure from the original concept , and which was not a success!
Below is a brief sample of what I found in his notebooks.
BALLISTIC TESTS & THEORIES
Leonardo knew a thing or two about ballistics, carrying out various empirical
tests on shooting from tiller bows and observing parabolic trajectories
(some 200 years before Newton set out the theory).
"...test it first and state the rule
afterward".
Alongside his various notes on bow tests he wrote calculations of
force and distance achieved with different setups
The little fellow on the right is a sketch in the margin
of the notebook, Illustrating a treatise on the forces of nature, where
he used the analogy of a flight archer to describe the effect of impetus
on the energy imparted to an arrow, The best modern day longbow flight archers
use the technique exactly as described by Leonardo.
INNOVATIVE MACHINES
Giant ballistas were well known in Leonardo's day, his design (above left) pushed technology further, and many think this machine was outside the technology of his day. Something which he also worked on his work included new methods of forging for mass production which could have assisted fabrication of giant bands to strap imbs together. His design for a repeating crossbow (on the right) used a treadmill (a common source of power in his day) to load each bow, calculations alongside involved the length of rope used to span the bows, weight and number of men on the treadmill and calculating the rquired leverage, Leonardo stated that "it appears clear that if you place over the head of the lever 20 men weighing 4,000 pounds, they will exert against the counter lever a force of 120,000 pounds, enough to charge four crossbows."
This is only a small part of my findings...
Some further reading/reference:
Selections from the Notebooks of Leonardo da Vinci: Irma A Richter
The Literary Works of Leonardo da Vinci: Edited Jean Paul Richter
The Notebooks of Leonardo da Vinci: trans. E MacCurdy
The Drawings of Leonardo da Vinci: A E Popham
Inventing Leonardo: A R Turner
Leonardo the Inventor: Heydenrich
The inventions of Leonardo da Vinci:Charles Gibb-Smith
Mediaeval Warfare Source book: D Nicolle