Speaking Machine - 会说话的机器 - 토킹 머신 - Replica Hindenburg

Speech synthesis
Speaking Machine by Wolfgang von Kempelen 1791
from the Book:
Mechanismus der menschlichen Sprache nebst der Beschreibung seiner sprechenden Maschine
Mechanism of human speech together with a description of its speaking machine

https://books.google.at/books?id=o_Y4zwEACAAJ&printsec=frontcover&hl=de&source=gbs_ge_summary_r&cad=0#v=thumbnail&q&f=false

REPLICA "Hindenburg":
The first publication of a speaking machine by Kempelen was in 1784 in:
Ueber den Schachspieler des herrn von Kempelen Nebst einer Abbildung und Beschreibung seiner Sprachmaschine.
to be found
https://www.digitale-sammlungen.de/de/view/bsb11081488?page=,1

by Carl Friedrich Hindenburg.

It contains the first drawings and brief descriptions of the functions of the keys.

According to Hindenburg, Mr. Kempelen was involved in the publication of the drawing

The machine you can see has different components than the machine that Kempelen published in his book in 1791, so it was probably an experimental version.