Section 10. The by-laws may be amended at any annual meeting, or at a special meeting called for the purpose, by a majority vote of all of the members present and entitled to vote; provided, however, that the notice of the meeting and of the proposed amendment is given each member in the manner prescribed in said by-laws. No amendment or amendments containing a change in the conditions of residence, occupation or association which qualify persons for membership shall become operative until approved in writing by the commissioner.