He ( = E. D. Morel) was not, like me, in the frrst division (Brixton Prison), and he suffered an injury to his health from which he never recovered. In spite of all this, his courage never failed. He often stayed up late at night to comfort Ramsay MacDonald, who frequently got 'cold feet', but when MacDonald came to form a government, he could not think of including anyone so tainted with pro-Germanism as Morel. Morel felt his ingratitude deeply, and shortly afterwards died of heart disease, acquired from the hardships of prison life.
Source: The Autobiography of Bertrand Russell, v.2
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