…but I did manage a photo or two of this evening’s experiments.  The shot into the right temporal bone that was administered yesterday, struck too far back and ripped out the bone on the edge of the skull.  However, that shot still punched a single, well-defined corner of a square hole in the bone not  effected by the break out.  It was at least a hint that we were on the right track.

I set up another test at even lower power.  This time the target was the thick frontal bone.  Aiming at these close ranges is as simple as projecting the path of the bolt with a broom handle.   Not evident in this photo is the presence of my heavy roll away tool chest that I crouch behind for protection at the moment of firing.

I cocked Firefly to her first notch and noticed that the limbs were barely drawn back at all.  Draw length is a mere 13″.

And yet it was sufficient to drive the 6 3/8″ long bolt head into the frontal bone of a new pig’s head, to a depth of 4″.  The hole it left has the cleanly cut indications of a square, very similar to the wound in the Maiden Castle skull.

Note the longitudinal crack in the frontal bone.   That is something not evident in the artifact.  There are a good many imponderables working against the  methodology we are using here.  The evident thickness of a pig’s frontal bone compared to a human’s temporal bone,  being chief among them.

I am still not sure how close an analog any of this actually is for the square shaped wound in the Maiden Castle skull.  The temporal bone of any human, even a brawny Durotrigen, seems so conveniently thin a place for a blow to be directed to.   For a Roman execution squad wielding pilums,  it’s a very likely place they would have made their thrust.  This pilum theory was advanced convincingly by Mr. Wilkins in the BBC program  that covered this topic.  The mystery of the Maiden Castle skull is a far from settled matter in my mind.  If anything, I tend to favor the pilum theory.   The set of conditions needed to punch a square hole in thin bone seems to be a lot narrower with a speeding ballista bolt than it would be with the thrust of a hand driven spear point.  I suppose for this set of tests to be complete I will need to make up a pilum and take a few stabs at Porcus with it.  Every experiment needs its control group.

While I have my doubts about the methodology we are pursuing here; still, all this probably means something, right?  If nothing else, I am developing techniques for test firing in a more lab-like setting.   It is important to use shielding in these close range tests to protect the operator from any potential bounce-backs or ricochets.   Clearly it doesn’t take much in the way of energy to knock a hole in one’s head with a sharp pointy thing.  I wouldn’t want to inadvertently find myself in the role of the perfect analog.

Also,  I still need to move Firefly back to the old test range and measure the speed of today’s shot by performing one just like it over our Doppler chronograph.  Then the pondering can really begin.

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Okay, it’s a few days later now, and I’ve come back to do those velocity readings on these slow shots.  The shot that made the square hole seen above, with a 13″ draw, was slouching along at 105 fps.  The shot from the previous day, with a 15 1/2″ draw and made into the pig’s temporal bone, was going 133 fps.  I’m somewhat surprised that these speeds are as high as they are given the laughably short draw lengths and limb retraction.

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