I'm not confident about how common the use of netting was in the CSN. There seems to have been serious problems at many of the building sites for the ironclads to acquire some pretty basic materials, not just the frills. An example would be CSS Arkansas. She lacked the firebrick around her funnel which should have insulated it from the rest of the ship. The result was a hotter than blazes gun deck and in July! For vessels that might have used netting, I suspect they used fishing nets. Some years ago I worked for an aerospace company in S. California which was involved in testing devices that explosively separated from a main body. We used nets to limit the spread pattern for safety reasons. One of the riggers explained that the tensile strength of these systems was a minor issue. The real goal was to have some "give" and use the net to slow the object down and minimize impact. The same principal was later used in devices that popped up from truck bodies to "catch" unmanned aerial vehicles. What I'm really saying is that you don't want the net to be drum tight, it fails quicker than one with some slack.