To remind the reader unfamiliar with Spanish science that the personality I am referring to is considered the "Father of Spanish Physics" and is so for his work in many facets, as a professor, academic, researcher, popularizer, and writer. Driven from the beginning by the colossal scientist Santiago Ramón y Cajal through the Board of Advanced Studies, he left Spain and contacted leading figures such as Einstein, Marie Curie, and many others to learn from them and then return to Spain to continue working and building a school. He did so in 1912, and just 11 years later, in 1923, Albert Einstein himself, Nobel laureate that year, visited Spain for the first and only time, where he received honors from various institutions and the King, with his friend and colleague Blas Cabrera acting as host.
In 1919, Marie Curie, a double Nobel Prize winner, was also received in Madrid with Cabrera as host, to hear the story of her dedication to science and saving human lives with the novel technique of X-rays, which would lead her to the grave a decade later due to overexposure to radiation. My father, Luis Cabrera Sánchez, recalled the visits to his house in Madrid by some of the great physicists such as Sommerfeld, Bohr, or Einstein, with some musical evenings where his mother, María Sánchez Real, accompanied Einstein on the violin on the piano. The frequent contacts with the scientific personalities of the time earned him international recognition and also placed Spain on the European scientific map, especially from 1926 when the Rockefeller Foundation decided to bet on Blas Cabrera with an investment of $420,000 of the time, leading to the birth of the National Institute of Physics and Chemistry, next to the current headquarters of the CSIC in Madrid. In 1928, he was appointed a member of the French Academy of Sciences and a member of the Scientific Committee of the Solvay Congresses, from 1928 to 1933, considered the most important Physics congresses in history. They discussed some of the most important problems related to the structure of matter and Quantum Physics, which marked the most important revolution in scientific thought, a precursor to the nanotechnology that surrounds us today, in a collective effort that still continues.
The precision and methodology of the experimental results of Blas Cabrera and his collaborators at the Rockefeller Institute were decisive for the later Nobel Prize winner in Physics, Van Vleck, to finally lay the quantum foundations of the Magnetism of matter as we know it today. In the early 1930s, Albert Einstein was forced to take refuge in the USA, fleeing Nazi terror, a prelude to the tsunami that would cause the collective exodus of geniuses never before seen in humanity: first in Spain between 1936 and 1939, and then with the Second World War until 1945. Blas Cabrera was forced into exile in France in 1937, where he was maintained thanks to a modest salary as secretary of the Institute of Weights and Measures, until the regime forced him to resign from the position and go into exile in Mexico, where the National Autonomous University welcomed him in 1941 as a professor of "Atomic Physics" and "History of Physics" until his death on August 1, 1945, due to Parkinson's disease, which worsened during his exile. In this situation, and making a final vital effort, he wrote a text that, to this day, remains as an unpublished manuscript hidden from the scientific and educational community: "History of Physics." This book was his last wish to leave a legacy to Spain and Mexico, to the scientific world in general.
And where is this manuscript? Well, this, in addition to an uncertain number of other manuscripts such as "Theory of Relativity," written in 1934 for the International University of Santander, letters, and the entire documentary legacy of Blas Cabrera, is under the custody of D. Francisco González de Posada, as president of the association "Friends of Scientific Culture," who received it on loan from the physicist Nicolás Cabrera Sánchez, son of Blas Cabrera, around 1986, with the aim of promoting events to disseminate his figure and also with the purpose of celebrating his 50th anniversary in 1995. This took place with events on the islands of Lanzarote, Gran Canaria, and Tenerife, like the previous centenary in 1978.
In Lanzarote, the Blas Cabrera center was opened in the Casa de los Arroyo in Arrecife, where an exhibition with the entire legacy, including the manuscripts, which several witnesses saw, was kept open and financed by the Island Council, and lasted until 2004 when the Council terminated the contract with the Friends of Scientific Culture association presided over by González de Posada, for reasons that will be documented in the Institution. 18 years have passed until the present, none of the referred manuscripts have been published, and the legacy has not been returned by Mr. González de Posada to the heirs.
In 2021, the Illustrious Professor and Chair of History of Science at the Autonomous University of Madrid and Academician Mr. D. José Manuel Sánchez Ron has published a masterful and very detailed book, a historical reference, entitled "Blas Cabrera, Spanish and Universal Scientist" [1] in which he states that "...Unfortunately, those who keep this manuscript have not fulfilled such a desire," referring to the publication of the manuscript "History of Physics." Upon learning of this publication, the undersigned and two heiresses sent him three burofaxes, from January to July of this year, requesting the return of the legacy. 8 months have passed since the first one, and to date, none has received a documented response.
The matter is very simple, Don Francisco: Either you have the will to return the legacy, or you do not. Silence is not an option and can only be interpreted as a refusal. Why do you not return the legacy and hide the manuscripts? Manuscripts whose existence you yourself have affirmed, using your own writings and words reiterated in the catalog of the Lanzarote exhibition [2] where you state that they are "...in showcases, copies of the original works and specifically of his published books and numerous unpublished manuscripts."
Moreover, in his book "Blas Cabrera before Einstein and Relativity" [3], you yourself present the first page of the manuscript relating to the course at the Summer University of Santander, and announce a "forthcoming" edition of the "commented" text, which has not taken place after no less than 27 years. Some manuscripts and personal letters from, among others, scientists of the stature of Nobel Prize winner Erwin Schrödinger, which constitute a cultural, historical, and scientific heritage of this country, which cannot allow even a minute more to remain hidden or forgotten.
Finally, I must tell you that the heirs must legally demand the return of the legacy, because if they do not, on August 2, 2025, they will have lost all rights to the domain due to the passage of 80 years since the author's death, against anyone who claims ownership of the historical legacy for themselves. The family wants to recover it to make it available to the scientific and educational community and to Spain, but it is possible that they will not succeed, and the family and I with it, will have to resign ourselves. But be assured that I will continue to reproach you until my last breath for the disloyalty you perpetrate every day that passes without returning it, to Blas Cabrera, Nicolás Cabrera, to the Spanish scientific community, and to Mexico and Latin America as well. If, on the contrary, you decide to heed my demand from this letter, I will not hesitate to publicly acknowledge your lordship.
Signed, Luis Blas Cabrera, grandson.
Bibliography [1] José Manuel Sánchez Ron, Blas Cabrera, Spanish and Universal Scientist, Madrid: Catarata, 2021.
[2] Francisco González de Posada et al., "Blas Cabrera, Life and Work of a Scientist," Madrid: Friends of Scientific Culture, 1995; Francisco González de Posada, Blas Cabrera, Spanish Physicist, Illustrious Lanzaroteño., Las Palmas de Gran Canaria: Friends of Scientific Culture, 1994.
[3] Francisco González de Posada, "Blas Cabrera before Einstein and Relativity", Las Palmas de Gran Canaria: Ayto. de Las Palmas de Gran Canaria, 1995
