Private companies pioneered the making of stamp coils in the United States. At first, firms that made stamp vending or affixing machines tried to use strips of regular sheet stamps to produce coils for their machines. But the normal perforations or holes between U.S. stamps were too weak to make coils, which sometimes broke apart.
Starting in 1906, the government issued imperforate sheets of stamps. The companies cut these sheets into strips and pasted the strips together to make coils. Then they added their own unique perforations, creating a wealth of stamp varieties. Benjamin Miller was keeping up with the latest trend when he collected them.