Respuesta :
In this excerpt from Ernest Shackleton’s memoir South!, the word which could best replace the word irradiated is permeated.
Irradiated refers to something which illuminates or something which enlightens spiritually and intellectually.
On the other hand, permeated refers to pervade or pass into every part of something.
Hence, in the above sentence permeated effectively replaced the word irradiated as the happiness passed into every part of their thirst, and weakness through the glimpse of the black cliffs of south Georgia.