recommendation letters

From Letters of Note: 

In November of 1911, two of the world's most revered scientists, Henri Poincaré and Marie Curie, were asked to write letters of recommendation for a 32-year-old man who was looking to become a professor of theoretical physics...

Two extracts.

First, Poincaré:

What one has to admire in him above all is the facility with which he adapts himself to new concepts and knows how to draw from them every possible conclusion.

Now Curie: 

I was able to appreciate the clarity of his mind, the extent of his documentation and the depth of his knowledge.