Section 29
SEC. 29. After at least the second installment has been paid and after the cultivation of the land has been begun, the purchaser, with the approval of the Secretary of Agriculture and Natural Resources, may convey or encumber his rights to any person, corporation or association legally qualified under this Act to purchase agricultural public lands, provided such conveyance or encumbrance does not affect any right or interest of the Government in the land. Any sale and encumbrance made without the previous approval of the Secretary of Agriculture and Natural Resources shall be null and void and shall produce the effect of annulling the acquisition and reverting the property and all rights thereto to the Government, and all payments on the purchase price theretofore made to the Government shall be forfeited. After the sale has been approved, the vendor shall not lose his right to acquire agricultural public lands under the provisions of this Act, provided he has the necessary qualifications.