The Secretary of the Treasury is authorized, upon request of the Secretary of the Interior and upon approval of the President, to transfer from time to time to the credit of the reclamation fund created by , such sum or sums, not exceeding in the aggregate $5,000,000, as the Secretary of the Interior may deem necessary for the construction and operation of reclamation projects authorized under the Act of (), and under way on , and Acts amendatory thereof or supplementary thereto.section 391 of this title32 Stat. 388June 17, 19021902-06-17March 3, 19311931-03-03