Section 26. In addition to the purposes for which a company may increase its capital stock or issue bonds, as provided in the preceding section, a company to supply itself with working capital may, in accordance with sections twenty-eight, twenty-nine and thirty-one of this chapter or sections fifty to fifty-two, inclusive, of chapter one hundred and fifty-nine, in the case of companies to which said last named sections are applicable, and of sections forty-seven to fifty-five, inclusive, of chapter one hundred and sixty, increase its capital stock to an amount not exceeding five per cent of the par value thereof then outstanding, or may issue bonds, secured by mortgage or otherwise, to such an amount, beyond the amounts fixed and limited by its agreement of association, or by any general or special law, and not more than the department shall determine will be properly required therefor, as the department shall approve as being consistent with the interest of the public and of the stockholders of such company and as not unreasonably reducing the security of any bond previously issued.