Any assignment by an insolvent debtor of his property for the benefit of his creditors in which any preference or priority is given to any creditor or creditors of the debtor by the terms of the assignment over any other creditor or creditors, other than as to any debts due to the public, or in which any provision or disposition of the property so assigned is made or directed other than that it be distributed among all creditors of the insolvent debtor equally, in proportion to the amount of their several demands and without preference or priority of any kind whatsoever, save only as to debts due to the public and save only as to such creditors as may accept the terms of such assignment and execute a release of their claim against the debtor, and except as hereinafter provided, shall be absolutely null and void and of no effect whatsoever.