Nicolás Achúcarro Lund (Bilbao, 1880-Guetxo, 1918) was probably one the most brilliant scientists of the now universally recognised Spanish Histological School. Despite his early death at the age of 37 years, his scientific production was very fruitful and of great neuroscientific relevance. His microscopy research marked the beginning of the outstanding work by his most important student, Pío del Río-Hortega. Both figures are unquestionably responsible for the most relevant neuropathological research conducted in Spain. The aim of the present study is to disseminate the document drafted by Achúcarro in August 1907, which was presented to the Council for Study Extensions and Scientific Research (JAE, for its Spanish initials), applied for a grant of 4000 francs. Achúcarro wrote the document 12 months before travelling to the Government Hospital for the Insane in Washington. The content of this document has not previously been referenced in the frequent biographical studies performed on Achúcarro. The document presents an almost autobiographical account o the scientific activity conducted by Achúcarro up to 1907. As a primary source of information, the document mentions some biographical aspects that are not widely known, as well as his scientific interests and his opinion on the European institutions where he had worked. Achúcarro' s study grant application was ultimately not approved by the Ministry for Public Education. Similar circumstances also affected his student and close friend Gonzalo Rodríguez Lafora. This study, which also addresses other documents on Achúcarro from the archive of the JAE, contextualises the contents of these documents by discussing the relations between Achúcarro and the JAE and the reasons that led to the rejection of his application.