(1) fifteen or more persons shall make and sign a certificate stating the name of such association, the fact that the association is formed under and for the purposes prescribed in this subchapter, the town or city where the association is located;
(2) such certificate shall be filed in the office of the Lieutenant Governor, who shall issue his certificate, declaring the facts contained in such original certificate, and the filing and recording thereof in his office;
(3) such certificate shall thereupon be filed with the Banking Board. Thereupon, the persons named in the original certificate, their associates and successors shall become a corporate body.