In the summer of 1994, my first year of college, I found what I believe to be a WWI combatives manual. It was a thin book with hand drawn illustrations demonstrating some very interesting techniques that I have kept with me to this day.
One of the techniques is called the Chin Jab. The idea is to hit your opponent on the underside of their chin like an uppercut, with an open palm strike, and then immediately follow up with a claw to the eyes.
This technique can be combined with a knee to the groin, a take down technique, and the shin scrape which I will talk about later.
I recently had a friend come visit me from a far. He is a long time friend and fellow martial artist, so I showed him the Chin Jab and we discussed/explored the technique.
We tried to figure out the context of the technique, in other words, the manner in which it was meant to be used. We talked about what the battlefield was like in WWI and WWII. We brought up scenarios such as a POW trying to escape situation, sentry removal, and fighting in the trench. We talked about various weapons that the soldiers carried and used in battle at the time, such as the trench knife, pistol, grenade, and bayonet rifle.
The main scenario we focused on was a soldier trying to take away another soldier's bayonet rifle. We mimicked the bayonet rifle using a thick PVC pipe I occasionally use for Eskrima training.
The key points:
A) You are engaged in a standing grappling situation.
B) The Chin Jab is not executed like a right cross where your trying to hit them with all your might in order to KO the enemy, but instead, your lifting their chin up to compromise their structure.
C) Immediately follow up with the claw. The claw must be a continuous clawing motion attacking sensitive areas of the face including eyes, nose, and ears.
We also lightly tested the claw in a ground fight scenario. We took turns taking each other down and tried to dominate or finish the other person on the ground while the other defended using the claw. The claw seemed very effective to throw the grappler off their game.
The Shin Scrape was another technique from the same manual. The idea is to kick a person in the knee, then scrape down their shin to land in a heel stomp to their foot. I like this triple attack combo, although I am not sure how well one can scrape down the shin if the enemy is wearing boots. I would imagine that the laces and such would get in the way.