What Are burst cylinders?
(That were apart of the Colt Walker pistol)

A burst/rupture disc is a feature installed on the valve of a cylinder allowing gas to escape in the event of a rapid expansion of the gas stored within a cylinder. Since it is unlikely that someone will be around in the event of a fire to open the valve to vent the gas, something needs to allow the gas to escape prior to the cylinder rupturing.

Explanation:

the great wall of china worked as a defense for the feudal states of the zhou dynasty to the north. during the warring states period more walls were put up to defend the borders of the different kingdoms. it was semi successful because despite the wall, the mongols eventually conquered china also the great wall provided protection to the economic development and cultural progress, safeguarded the trading routes such as the silk road, and secured transmission of information and transportation. @jayxboof

answer: sorry but maybe take a pic of the map so nobody's confused

explanation: