Equal portion of rights and interest in a company. Sink a loan. To pay off a loan. To redeem a series of bonds. Sinking fund bonds .
Money is accumulated regularly in special accounts so companies can repay loans easily at maturity.
Theoretically, sinking fund bonds are safer investments. An ordinarily-produced certificate preserved in unissued form for counterfeit detection and other purposes. Specimens are usually minimally punch cancelled. And ornamental box to allow uniform placement of an adhesive revenue stamp. Usually found on the left side of stock certificates used in the 1860s and 1870s.