Jacobus Publicius was a fifteenth-century rhetorician and physician who is remembered today for being the author of the first ars memoriae (or ars memorativa), a work dedicated to techniques concerning the organisation and improving of memory. Publicius' ideas were gathered in a book called Ars Oratoria. Ars Epistolandi. Ars Memorativa published in 1482, which included this wonderful illustrated alphabet featured here. Each letter of the alphabet is paired with an object (in some case more than one) which echoes its shape. A is associated with a folding ladder, B with a mandolin, C with a horseshoe, and so on. Publicius' book proved very popular and influenced many subsequent scholars concerned with memory, including the English polymath Robert Fludd, who came up with his own mnemonic alphabet.
We are featuring the original 1482 edition here (see source link below), but you can also see a copy of the slightly expanded second edition (with additional imagery) at the Wolfenbütteler Digitale Bibliothek. For some further reading on the subject we recommend The Book of Memory (2008) by Mary Carruthers.