There are 1996 reprints with generous previews on Google Books, so check it out and see what you think. I don't know Spanish but there was a question in For Beginners at the end of 2025 with a position from book 1. That chapter featured exercises requiring the reader to count the number of moves available to each side in a given position. It seemed a bit like the Soviet Chess Primer but that was just an impression.
Has anyone read Roberto Grau's Tratado General de Ajedrez?
It turns out the four volumes were reprinted in 2020. See
Downloadable excerpts are also available.
In the blog post How to Climb from 1600 to 1800: Four Coaches Share Their Experience! by Flavia Cancio-Bello Ayes, one of the coaches, WFM Liliam Blanco García recommends the Tratado General de Ajedrez by the Argentinian chess player Roberto Grau (1900–1944). It was originally a four-part series published in the 1930s. The four volumes listed on Wikipedia are the following:
Tratado General de Ajedrez: Tomo I - Rudimentos
Tratado General de Ajedrez: Tomo ll - Estrategia (renamed "Táctica" in later editions)
Tratado General de Ajedrez: Tomo III - Conformación de peones
Tratado General de Ajedrez: Tomo IV - Estrategia superior
Has anybody read these books? If yes, what are they like?
(Apparently, they are still in print, though I could find only three volumes published by Editorial La Casa del Ajedrez: Rudimentos, Conformaciones de peones and Táctica y estrategia.)