1. Aracy drop hammer town south of Highland Village and Ogre cave of trolls.

2. Over - loading of strong flash pyrotechnic composite was studied by using drop hammer simulation device.

3. A number of shock waves, generated from simulating percussive drilling, have been measured using drop hammer test device and dynamic measurement system for shock wave.

4. Four screws anchored in a solid concrete block 60 × 60 × 60 cm hold the drop hammer in such a manner that the rails are absolutely vertical and the drop weight is easily guided.