At the age of 12, his mother advised him to leave for Lisbon where his maternal uncle, Lázaro Joaquim de Sousa Pereira, had established himself as a pharmacist.

As a long-standing member of the society's Public Health Commission, he played an important role in drawing attention to, and eventually regulating, various hazardous pharmaceutical practices.

In particular, Sousa Martins considered the Penhas Douradas formation near Manteigas to be the healthiest place in the country, thanks to its fresh and clean air.

Gathering in August 1881, a plethora of scientists and intellectuals came together to study the geographical, meteorological and anthropological aspects of the region in an unprecedented effort aimed at systematically exploring the Portuguese territory.

Following the expedition, Sousa Martins defended the implementation of sanatoriums in the mountain region, and was one of the founders of the foundation of Club Hermínio, a humanitarian association created in 1888 and active until at least 1892.

Sousa Martins' main objective was the construction of a sanatorium in Serra da Estrela that could permanently host and treat patients with pulmonary tuberculosis.

In spite of his efforts and influence with the Crown (he was an honorary doctor of the Royal House since 1888) and with the Government, the initiative, although universally supported, was slow to materialise, and the sanatorium he had proposed would not be built until after his death.

However, the disease worsened and after he contracted cardiac problems in addition to what now seemed to be terminal tuberculosis, Sousa Martins committed suicide on 18 August 1897 using a large injection of morphine.

The foot of the statue is surrounded by marble plaques giving thanks to him for unexpected cures, some calling him "Brother", candles burn all around it and flowers are placed there.