In 2015, Nicholas Yeager traveled across the United States on a motorcycle visiting 13 research libraries over three months. The travel blog https://motoscribendi.com describes Yeager's experiences and discoveries. Focused on calligraphic writing manuals, he cast his net wider than just wood or copper engraved instructional manuals. At the Cotsen Children's Library at Princeton's Firestone Library, Yeager found a didactic instructional item called a "spelling alphabets." These ivory disks had letters carved into the face of the disk and painted black to show off the letterform surrounded by the warm ivory color of the disk. A scene depicting the use of the letter (A for Apple) with an apple tree engraved and painted on the other side.
Upon his return, Yeager designed a digital typeface based on an alphabet by G. Cresci, a 16th century writing master. He then had Magnolia Editions laser cut the letters into wooden dowels for use as type called Percussive Roman. As seen here, he also had a set of letters laser cut into 1/2" thick dowels with the letters right-reading to make a modern day Spelling Alphabet.