This angle, therefore, divided by the magnifying power of the telescope gives the real angular distance of the centres of a double star.
The principal centres of the system are Buenos Aires, Rosario and Bahia Blanca, with La Plata as a secondary centre to the former, and from these the lines radiate westward and northward.
Another group in the north of France has its centres at Lille, Tourcoing, Roubaix, St Quentin and Amiens.
Each arrondissement is divided into sousarrondissements, having their centres in the great commercial ports, but this arrangement is purely for the embodiment of the men of the Inscription Maritime, and has nothing to do with the dockyards as naval arsenals.
France is divided into sixteen academies or educational districts, having their centres at the seats of the universities.
