When any school district is abolished or altered under the provisions of this article, the abolition or alteration thereof shall not impair or release the property of such school district from liability for the payment of the bonds or other indebtedness of such district and it shall be the duty of the board of supervisors of said county to levy taxes on the property of said district so abolished or altered from year to year according to the terms of such indebtedness until same shall be fully paid. No existing school district shall be abolished unless the territory comprising such district shall be annexed to another district in the same order abolishing the former district.