The board of county commissioners has the right to sell any of such bonds, but no bond shall be sold unless for cash, and not then at a discount of more than fifteen percent of its par value. The money arising from the sale of such bonds shall be forthwith used for the objects for which the debt was created, and for no other purpose whatever. When any such bonds or any coupons are redeemed, the board of county commissioners, in the presence of the clerk of said board or his deputy, shall cancel such bonds or coupons by writing the word 'canceled' on the face of such bonds or coupons, and such board shall make a record of the proceedings, stating what bonds or coupons were canceled.G.L. § 452. G.S. § 675. R.S. 08: § 1368. C.L. § 8846. CSA: C. 45, § 198. CRS 53: § 36-6-5. C.R.S. 1963: § 36-6-5.