It is an interest coupon clipped from a bond. It looks like 7.0% paid twice a year on a $1,000.00 bond. (It says real estate mortgage, so technically not a bond but a promissory note. The effect is the same on the investor). This is coupon 7 from a bond issued May 1, 1874. Coupon 1 was paid November 1, 1874, 2 on May 1, 1875, etc.