On weights, a German lance-barrier, and diverting rivers to ford them
A falling-weight problem, a pike defence, and ancient captains dividing deep rivers
The page opens with a headed physics inquiry, 'De ponderibus', posing how deeply a falling weight drives into the ground as its fall-height, mass and breadth change. Military notes follow: pavise-mantlets to pass through an arrow-storm, and the German manner of interweaving long lances into a hedge with one end set on the ground, illustrated by the hatched thicket of strokes at the top. Two further notes on crossing high or deep rivers cite ancient captains who divided a river into many streams or cut draining channels to lower it.
On this page
De ponderibus: how deep a falling weight drives
If a one-pound weight falling 2 braccia sinks a span into the ground, how far will it sink falling 40 braccia, or how far will a 2-pound weight sink falling 2 braccia? A second question asks, for a weight of breadth a and the same weight of doubled breadth dropped from the same height, how much more the narrower breadth drives in than the wider, the ground being of equal resistance.
Pavise-mantlets against the arrow-storm
A short note explains that pavise-mantlets are made in order to pass through the fury of the arrow-storm.
German close-set lance barrier
The Germans interlace and weave their long lances together, closing up in a body against the enemy, crouching and setting one end of each lance on the ground while holding the rest in hand. The dense diagonal hatching at the top of the sheet renders this hedge of shafts.
Dividing a river into many streams
If the water is too high for infantry or horsemen to cross, the river is reduced into many streams, as Cyrus king of the Persians did at the storming of Babylon, and as Alexander and Caesar did on other rivers. A wide river bend is sketched below the text.
Draining channels to lower a deep river
For a river too deep to ford, the captain has many channels dug that take up the water and return it lower down, so the river falls and is crossed easily. The note cites Alexander at the Hydaspes against Porus, Caesar in Gaul and Spain, and Hannibal crossing the Po with elephants.