Let E be a regular b.c.s. ( a Hausdoff l.c.s. ), and let F be a normed space. We consider the spaces El all bounded ( continuous ) linear mappings of E into F, provided with its natural topology ( its equi continuous bornology ) . By defíning E^n= (E^n-1 )^1 for every n 1, we obtaín a sequence (E^n)n composed by, alternatively, b.c.s. and l.c.s.. We study the inclusion of E into E^2, giving a necessary and sufficient condition for a regular b.c.s. to be polar.