It having been found that ricochets, especially over water, were apt to extinguish these fuzes, a safety cap and primer combined have been adopted in the navy. A recess in the top is filled with priming composition and covered, until the fuze is required for use, with a leaden disk which fits accurately the opening. A crooked passage filled with priming, conveys the fire to the fuze composition beneath, and prevents water from being forced in in sufficient quantity to extinguish the fuze.
17. When are paper fuzes for field shells and spherical case inserted?
At the moment of loading the gun, and into wooden fuze-plugs previously driven into the shell.
18. What is a port-fire?
It consists of a small paper-case filled with a highly inflammable but slow burning composition, the flame of which is very intense and penetrating, and cannot be extinguished by water.
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19. What is it used for?
Principally as an incendiary material in loading shells, and for communicating fire to the priming of guns when proving them.
20. What does port-fire composition consist of?
Of nitre, sulphur, and mealed powder, in different proportions. One kind is composed of