Halberd the 16th through 18th centuries. In the British army, sergeants continued to carry halberds until 1793, when they were replaced by pikes with cross bars. The 18th century halberd had, however, become simply a symbol of rank with no sharpened edge and insufficient strength to use as a weapon. It served as an instrument for ensuring that infantrymen in ranks stood correctly aligned with each other and that their muskets were aimed at the correct level. Halberd A halberd (also called halbard, halbert or Swiss voulge) is a two-handed pole weapon that came to prominent use during the 14th and
Types of volcanic eruptions propels it forward. Phreatomagmatic eruptions are another type of volcanic eruption, driven by the compression of gas within magma, the direct opposite of the process powering magmatic activity. The third eruptive type is the phreatic eruption, which is driven by the superheating of steam via contact with magma; these eruptive types often exhibit no magmatic release, instead causing the granulation of existing rock. Within these wide-defining eruptive types are several subtypes. The weakest are Hawaiian and submarine, then Strombolian, followed by Vulcanian and Surtseyan. The stronger eruptive types are Pelean eruptions, followed by Plinian eruptions; the strongest eruptions are called